-<!-- $Header: /cvsroot/pgsql/doc/src/sgml/Attic/pygresql.sgml,v 1.6 2002/03/27 19:19:22 petere Exp $ -->
+<!-- $Header: /cvsroot/pgsql/doc/src/sgml/Attic/pygresql.sgml,v 1.7 2002/09/23 21:10:12 petere Exp $ -->
<chapter id="pygresql">
<title><application>PyGreSQL</application> - <application>Python</application> Interface</title>
<itemizedlist>
<listitem>
<para>
- If you are on <acronym>NetBSD</acronym>, look in the packages
- directory under databases. If it isn't there yet, it should be
- there shortly. You can also pick up the package files from
- <ulink url="ftp://ftp.druid.net/pub/distrib/pygresql.pkg.tgz"
- >ftp://ftp.druid.net/pub/distrib/pygresql.pkg.tgz</ulink>. There
- is also a package in the <acronym>FreeBSD</acronym> ports
- collection but as I write this it is at version 2.1. I will try
- to get that updated as well.
- </para>
- </listitem>
-
- <listitem>
- <para>
- For Linux installation look at <filename>README.linux</filename>.
- If you're on an <acronym>x86</acronym> system that uses
- <acronym>RPMs</acronym>, then you can pick up an
- <acronym>RPM</acronym> at <ulink
- url="ftp://ftp.druid.net/pub/distrib/pygresql.i386.rpm"
- >ftp://ftp.druid.net/pub/distrib/pygresql.i386.rpm</ulink>.
- </para>
- </listitem>
-
- <listitem>
- <para>
Note that if you are using the <acronym>DB-API</acronym> module
- you must also install <
acronym>mxDateTime</acronym> from <ulink
+ you must also install <
literal>mxDateTime</literal> from <ulink
url="http://starship.python.net/~lemburg/mxDateTime.html"
>http://starship.python.net/~lemburg/mxDateTime.html</ulink>.
</para>
<listitem>
<para>
Also, check out <filename>setup.py</filename> for an alternate
- method of installing the package using Python's Distutils.
+ method of installing the package using <application>Python</application>'s Distutils.
</para>
</listitem>
-
</itemizedlist>
<para>
You have two options. You can compile
- <productname>PyGreSQL</productname> as a stand-alone module or you
- can build it into the <productname>Python</productname>
+ <application>PyGreSQL</application> as a stand-alone module or you
+ can build it into the <application>Python</application>
interpreter.
</para>
<itemizedlist>
<listitem>
<para>
- You must first have installed <productname>Python</productname>
+ You must first have installed <application>Python</application>
and <productname>PostgreSQL</productname> on your system. The
header files and developer's libraries for both
- <productname>Python</productname> and
+ <application>Python</application> and
<productname>PostgreSQL</productname> must be installed on your
- system before you can build <productname>PyGreSQL</productname>.
- If you built both <productname>Python</productname> and
+ system before you can build <application>PyGreSQL</application>.
+ If you built both <application>Python</application> and
<productname>PostgreSQL</productname> from source, you should be
fine. If your system uses some package mechanism (such as
- <acronym>RPM</acronym> or <acronym>NetBSD</acronym> packages),
+ <acronym>RPM</acronym> or <systemitem class="osname">NetBSD</systemitem> packages),
then you probably need to install packages such as
- <acronym>Python-devel</acronym> in addition to the
- <productname>Python</productname> package.
+ <application>Python-devel</application> in addition to the
+ <application>Python</application> package.
</para>
</listitem>
<listitem>
<para>
- <productname>PyGreSQL</productname> is implemented as three
- parts, a C module labeled <acronym>_pg</acronym> and two
- <productname>Python</productname> wrappers called
+ <application>PyGreSQL</application> is implemented as three
+ parts, a C module labeled <literal>_pg</literal> and two
+ <application>Python</application> wrappers called
<filename>pg.py</filename> and <filename>pgdb.py</filename>.
This changed between 2.1 and 2.2 and again in 3.0. These
changes should not affect any existing programs but the
<listitem>
<para>
- Download and unpack the <productname>PyGreSQL</productname>
+ Download and unpack the <application>PyGreSQL</application>
tarball if you haven't already done so.
</para>
</listitem>
<itemizedlist>
<listitem>
<para>
- [pyInc] = path of the <productname>Python</productname>
+ [pyInc] = path of the <application>Python</application>
include (usually <filename>Python.h</filename>)
</para>
</listitem>
<itemizedlist>
<listitem>
<para>
- <literal>-DNO_DEF_VAR</literal> - no default variables
+ <option>-DNO_DEF_VAR</option> - no default variables
support
</para>
</listitem>
<listitem>
<para>
- <literal>-DNO_DIRECT</literal> - no direct access methods
+ <option>-DNO_DIRECT</option> - no direct access methods
</para>
</listitem>
<listitem>
<para>
- <literal>-DNO_LARGE</literal> - no large object support
+ <option>-DNO_LARGE</option> - no large object support
</para>
</listitem>
<listitem>
<para>
- <literal>-DNO_SNPRINTF</literal> - if running a system with
+ <option>-DNO_SNPRINTF</option> - if running a system with
no snprintf call
</para>
</listitem>
<listitem>
<para>
- <literal>-DNO_PQSOCKET</literal> - if running an older
+ <option>-DNO_PQSOCKET</option> - if running an older
<productname>PostgreSQL</productname>
</para>
</listitem>
</itemizedlist>
On some systems you may need to include
- <literal>-lcrypt</literal> in the list of libraries to make it
+ <option>-lcrypt</option> in the list of libraries to make it
compile.
- Define <literal>DNO_PQSOCKET</literal> if you are using a
+ Define <option>DNO_PQSOCKET</option> if you are using a
version of <productname>PostgreSQL</productname> before 6.4 that
does not have the <function>PQsocket</function> function. The
other options will be described in the next sections.
<para>
Finally, move the <filename>_pg.so</filename>,
<filename>pg.py</filename>, and <filename>pgdb.py</filename>
- to a directory in your <literal>PYTHONPATH</literal>.
+ to a directory in your <envar>PYTHONPATH</envar>.
A good place would be
<filename>/usr/lib/python1.5/site-python</filename>
- if your <productname>Python</productname> modules are in
+ if your <application>Python</application> modules are in
<filename>/usr/lib/python1.5</filename>.
</para>
</listitem>
<para>
Find the directory where your <filename>Setup</filename>
file lives (usually <filename>??/Modules</filename>) in
- the <productname>Python</productname> source hierarchy and
+ the <application>Python</application> source hierarchy and
copy or symlink the <filename>pgmodule.c</filename> file there.
</para>
</listitem>
<listitem>
<para>
- Add the following line to your Setup file
- <ProgramListing>
+ Add the following line to your <filename>Setup</> file
+<programlisting>
_pg pgmodule.c -I[pgInc] -L[pgLib] -lpq # -lcrypt # needed on some systems
- </ProgramListing>
+</programlisting>
where:
<itemizedlist>
<listitem>
<itemizedlist>
<listitem>
<para>
- <literal>-DNO_DEF_VAR</literal> - no default variables
+ <option>-DNO_DEF_VAR</option> - no default variables
support
</para>
</listitem>
<listitem>
<para>
- <literal>-DNO_DIRECT</literal> - no direct access methods
+ <option>-DNO_DIRECT</option> - no direct access methods
</para>
</listitem>
<listitem>
<para>
- <literal>-DNO_LARGE</literal> - no large object support
+ <option>-DNO_LARGE</option> - no large object support
</para>
</listitem>
<listitem>
<para>
- <literal>-DNO_SNPRINTF</literal> - if running a system with
+ <option>-DNO_SNPRINTF</option> - if running a system with
no snprintf call
</para>
</listitem>
<listitem>
<para>
- <literal>-DNO_PQSOCKET</literal> - if running an older
+ <option>-DNO_PQSOCKET</option> - if running an older
<productname>PostgreSQL</productname>
</para>
</listitem>
</itemizedlist>
- Define <literal>DNO_PQSOCKET</literal> if you are using a version of
+ Define <option>-DNO_PQSOCKET</option> if you are using a version of
<productname>PostgreSQL</productname> before 6.4
that does not have the <function>PQsocket</function> function.
The other options will be described in the next sections.
<listitem>
<para>
If you want a shared module, make sure that the
- <literal>*shared*</literal> keyword is uncommented and
+ <literal>*shared*</literal> key word is uncommented and
add the above line below it. You used to need to install
your shared modules with <literal>make sharedinstall</> but this no
longer seems to be true.
</listitem>
<listitem>
<para>
- Rebuild <productname>Python</productname> from the root
- directory of the <productname>Python</productname> source
+ Rebuild <application>Python</application> from the root
+ directory of the <application>Python</application> source
hierarchy by running
- <ProgramListing>
+<programlisting>
make -f Makefile.pre.in boot
make && make install
- </ProgramListing>
+</programlisting>
</para>
</listitem>
<listitem>
]]>
+ <para>
+ You may either choose to use the old mature interface provided by
+ the <literal>pg</literal> module or otherwise the newer
+ <literal>pgdb</literal> interface compliant with the <ulink
+ url="http://www.python.org/topics/database/DatabaseAPI-2.0.html"
+ ><acronym>DB-API 2.0</acronym></ulink> specification developed by
+ the <application>Python</application> <acronym>DB-SIG</acronym>.
+ </para>
+
+ <para>
+ Here we describe only the older <literal>pg</literal>
+ <acronym>API</acronym>. As long as
+ <application>PyGreSQL</application> does not contain a description
+ of the <acronym>DB-API</acronym> you should read about the
+ <acronym>API</acronym> at <ulink
+ url="http://www.python.org/topics/database/DatabaseAPI-2.0.html"
+ >http://www.python.org/topics/database/DatabaseAPI-2.0.html</ulink>.
+ </para>
+
+ <para>
+ A tutorial-like introduction to the <acronym>DB-API</acronym> can be
+ found at <ulink
+ url="http://www2.linuxjournal.com/lj-issues/issue49/2605.html"
+ >http://www2.linuxjournal.com/lj-issues/issue49/2605.html</ulink>
+ </para>
+
<sect1 id="pygresql-pg">
<title>The <literal>pg</literal> Module</title>
<para>
- You may either choose to use the old mature interface provided by
- the <literal>pg</literal> module or otherwise the newer
- <literal>pgdb</literal> interface compliant with the <ulink
- url="http://www.python.org/topics/database/DatabaseAPI-2.0.html"
- ><acronym>DB-API 2.0</acronym></ulink> specification developed by
- the <productname>Python</productname> <acronym>DB-SIG</acronym>.
- </para>
-
- <para>
- Here we describe only the older <literal>pg</literal>
- <acronym>API</acronym>. As long as
- <productname>PyGreSQL</productname> does not contain a description
- of the <acronym>DB-API</acronym> you should read about the
- <acronym>API</acronym> at <ulink
- url="http://www.python.org/topics/database/DatabaseAPI-2.0.html"
- >http://www.python.org/topics/database/DatabaseAPI-2.0.html</ulink>.
- </para>
-
- <para>
- A tutorial-like introduction to the <acronym>DB-API</acronym> can
- be found at <ulink
- url="http://www2.linuxjournal.com/lj-issues/issue49/2605.html"
- >http://www2.linuxjournal.com/lj-issues/issue49/2605.html</ulink>
- </para>
-
- <para>
The <literal>pg</literal> module defines three objects:
<itemizedlist>
<listitem>
<listitem>
<para>
- <literal>pgqueryobject</literal> that handles query results.
+ <classname>pgqueryobject</classname> that handles query results.
</para>
</listitem>
</itemizedlist>
<para>
If you want to see a simple example of the use of some of these
functions, see <ulink url="http://www.druid.net/rides"
- >http://www.druid.net/rides</ulink> where I have a link at the
- bottom to the actual <productname>Python</productname> code for the
+ >http://www.druid.net/rides</ulink> where you can find a link at the
+ bottom to the actual <application>Python</application> code for the
page.
</para>
<para>
Some constants are defined in the <literal>pg</literal> module
dictionary. They are intended to be used as a parameters for
- methods calls. You should refer to the <literal>libpq</literal>
+ methods calls. You should refer to the <application>libpq</application>
description (<xref linkend="libpq">) for more information about
them. These constants are:
default variable, and forget it, without having to modify your
environment. The support for default variables can be disabled by
setting the <option>-DNO_DEF_VAR</option> option in the Python
- Setup file. Methods relative to this are specified by te tag [DV].
+ <filename>Setup</> file. Methods relative to this are specified by the tag [DV].
</para>
<para>
<refnamediv>
<refname>connect</refname>
- <refpurpose>opens a connection to the database server</refpurpose>
+ <refpurpose>open a connection to the database server</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
-connect(<optional><replaceable>dbname</replaceable></optional>, <optional><replaceable>host</replaceable></optional>, <optional><replaceable>port</replaceable></optional>, <optional><replaceable>opt</replaceable></optional>, <optional><replaceable>tty</replaceable></optional>, <optional><replaceable>user</replaceable></optional>, <optional><replaceable>passwd</replaceable></optional>)
+connect(<optional><parameter>dbname</parameter></optional>, <optional><parameter>host</parameter></optional>, <optional><parameter>port</parameter></optional>, <optional><parameter>opt</parameter></optional>, <optional><parameter>tty</parameter></optional>, <optional><parameter>user</parameter></optional>, <optional><parameter>passwd</parameter></optional>)
</synopsis>
<refsect2 id="pygresql-connect-parameters">
<variablelist>
<varlistentry>
- <term><replaceable>dbname</replaceable></term>
+ <term><parameter>dbname</parameter></term>
<listitem>
- <para>Name of connected database (string/None).</para>
+ <para>Name of connected database (string/<symbol>None</>).</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><replaceable>host</replaceable></term>
+ <term><parameter>host</parameter></term>
<listitem>
- <para>Name of the server host (string/None).</para>
+ <para>Name of the server host (string/<symbol>None</>).</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><replaceable>port</replaceable></term>
+ <term><parameter>port</parameter></term>
<listitem>
<para>Port used by the database server (integer/-1).</para>
</varlistentry>
<varlistentry>
- <term><replaceable>opt</replaceable></term>
+ <term><parameter>opt</parameter></term>
<listitem>
<para>
- Options for the server (string/None).
+ Options for the server (string/<symbol>None</>).
</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><replaceable>tty</replaceable></term>
+ <term><parameter>tty</parameter></term>
<listitem>
<para>
File or tty for optional debug output from backend
- (string/None).
+ (string/<symbol>None</>).
</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><replaceable>user</replaceable></term>
+ <term><parameter>user</parameter></term>
<listitem>
<para>
- <productname>PostgreSQL</productname> user (string/None).
+ <productname>PostgreSQL</productname> user (string/<symbol>None</>).
</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><replaceable>passwd</replaceable></term>
+ <term><parameter>passwd</parameter></term>
<listitem>
- <para>Password for user (string/None).</para>
+ <para>Password for user (string/<symbol>None</>).</para>
</listitem>
</varlistentry>
</variablelist>
<variablelist>
<varlistentry>
- <term><replaceable>pgobject</replaceable></term>
+ <term><parameter>pgobject</parameter></term>
<listitem>
<para>
<variablelist>
<varlistentry>
- <term><errorname>TypeError</errorname></term>
+ <term><classname>TypeError</classname></term>
<listitem>
<para>
</varlistentry>
<varlistentry>
- <term><errorname>SyntaxError</errorname></term>
+ <term><classname>SyntaxError</classname></term>
<listitem>
<para>
</varlistentry>
<varlistentry>
- <term><errorname>pg.error</errorname></term>
+ <term><classname>pg.error</classname></term>
<listitem>
<para>
- Some error occurred during pg connection definition.
+ Some error occurred during <literal>pg</> connection definition.
</para>
</listitem>
</varlistentry>
</variablelist>
<para>
- (+ all exceptions relative to object allocation)
+ (plus all exceptions relative to object allocation)
</para>
</refsect2>
</refsynopsisdiv>
<para>
This method opens a connection to a specified database on a given
<productname>PostgreSQL</productname> server. You can use
- keywords here, as described in the
- <productname>Python</productname> tutorial. The names of the
- keywords are the name of the parameters given in the syntax
+ key words here, as described in the
+ <application>Python</application> tutorial. The names of the
+ key words are the name of the parameters given in the syntax
line. For a precise description of the parameters, please refer
to the <productname>PostgreSQL</productname> user manual.
</para>
<variablelist>
<varlistentry>
- <term>string or None</term>
+ <term>string or <symbol>None</></term>
<listitem>
<para>
<variablelist>
<varlistentry>
- <term><errorname>SyntaxError</errorname></term>
+ <term><classname>SyntaxError</classname></term>
<listitem>
<para>
<para>
<function>get_defhost()</function> returns the current default
- host specification, or None if the environment variables should
+ host specification, or <symbol>None</> if the environment variables should
be used. Environment variables will not be looked up.
</para>
</refsect1>
<refentry id="pygresql-set-defhost">
- <refmeta>
- <refentrytitle>set_defhost</refentrytitle>
- <refmiscinfo>PYGRESQL - Connection Management</refmiscinfo>
- </refmeta>
- <refnamediv>
- <refname>set_defhost</refname>
- <refpurpose>set default host name [DV]</refpurpose>
- </refnamediv>
+ <refmeta>
+ <refentrytitle>set_defhost</refentrytitle>
+ <refmiscinfo>PYGRESQL - Connection Management</refmiscinfo>
+ </refmeta>
- <refsynopsisdiv>
+ <refnamediv>
+ <refname>set_defhost</refname>
+ <refpurpose>set default host name [DV]</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
<synopsis>
-set_defhost(<replaceable>host</replaceable>)
+set_defhost(<parameter>host</parameter>)
</synopsis>
- <refsect2 id="pygresql-set-defhost-parameters">
- <title>Parameters</title>
- <variablelist>
- <varlistentry>
- <term>
- <replaceable>host</replaceable>
- </term>
- <listitem>
- <para>New default host (string/None).</para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect2>
+ <refsect2 id="pygresql-set-defhost-parameters">
+ <title>Parameters</title>
+ <variablelist>
+ <varlistentry>
+ <term>
+ <parameter>host</parameter>
+ </term>
+ <listitem>
+ <para>New default host (string/<symbol>None</>).</para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect2>
- <refsect2 id="pygresql-set-defhost-return">
- <title>Return Type</title>
- <variablelist>
- <varlistentry>
- <term>
- string or None
- </term>
- <listitem>
- Previous default host specification.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect2>
+ <refsect2 id="pygresql-set-defhost-return">
+ <title>Return Type</title>
+ <variablelist>
+ <varlistentry>
+ <term>
+ string or <symbol>None</>
+ </term>
+ <listitem>
+ <para>
+ Previous default host specification.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect2>
- <refsect2 id="pygresql-set-defhost-exceptions">
- <title>Exceptions</title>
- <variablelist>
- <varlistentry>
- <term>
- <errorname>TypeError</errorname>
- </term>
- <listitem>
- Bad argument type, or too many arguments.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect2>
+ <refsect2 id="pygresql-set-defhost-exceptions">
+ <title>Exceptions</title>
+ <variablelist>
+ <varlistentry>
+ <term>
+ <classname>TypeError</classname>
+ </term>
+ <listitem>
+ <para>
+ Bad argument type, or too many arguments.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect2>
- </refsynopsisdiv>
+ </refsynopsisdiv>
- <refsect1 id="pygresql-set-defhost-description">
- <title>Description</title>
- <function>set_defhost()</function> sets the default host value
- for new connections. If None is supplied as parameter, environment
- variables will be used in future connections. It returns the
- previous setting for default host.
- </para>
- </refsect1>
+ <refsect1 id="pygresql-set-defhost-description">
+ <title>Description</title>
+ <para>
+ <function>set_defhost()</function> sets the default host value
+ for new connections. If <symbol>None</symbol> is supplied as parameter, environment
+ variables will be used in future connections. It returns the
+ previous setting for default host.
+ </para>
+ </refsect1>
</refentry>
<variablelist>
<varlistentry>
<term>
- integer or None
+ integer or <symbol>None</symbol>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>SyntaxError</errorname>
+ <classname>SyntaxError</classname>
</term>
<listitem>
<para>
<title>Description</title>
<para>
<function>get_defport()</function> returns the current default
- port specification, or None if the environment variables should
+ port specification, or <symbol>None</symbol> if the environment variables should
be used. Environment variables will not be looked up.
</para>
</refsect1>
<refsynopsisdiv>
<synopsis>
-set_defport(<replaceable>port</replaceable>)
+set_defport(<parameter>port</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-SET-DEFPORT-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>port</replaceable>
+ <parameter>port</parameter>
</term>
<listitem>
<para>New default host (integer/-1).</para>
<variablelist>
<varlistentry>
<term>
- integer or None
+ integer or <symbol>None</symbol>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- string or None
+ string or <symbol>None</symbol>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>SyntaxError</errorname>
+ <classname>SyntaxError</classname>
</term>
<listitem>
<para>
<title>Description</title>
<para>
<function>get_defopt()</function> returns the current default
- connection options specification, or None if the environment variables should
+ connection options specification, or <symbol>None</symbol> if the environment variables should
be used. Environment variables will not be looked up.
</para>
</refsect1>
</refmeta>
<refnamediv>
<refname>set_defopt</refname>
- <refpurpose>set options specification [DV]</refpurpose>
+ <refpurpose>set default options specification [DV]</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
-set_defopt(<replaceable>options</replaceable>)
+set_defopt(<parameter>options</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-SET-DEFOPT-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>options</replaceable>
+ <parameter>options</parameter>
</term>
<listitem>
- <para>New default connection options (string/None).</para>
+ <para>New default connection options (string/<symbol>None</symbol>).</para>
</listitem>
</varlistentry>
</variablelist>
<variablelist>
<varlistentry>
<term>
- string or None
+ string or <symbol>None</symbol>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
<title>Description</title>
<para>
<function>set_defopt()</function> sets the default connection options value
- for new connections. If None is supplied as parameter, environment
+ for new connections. If <symbol>None</symbol> is supplied as parameter, environment
variables will be used in future connections. It returns the
previous setting for default options.
</para>
<variablelist>
<varlistentry>
<term>
- string or None
+ string or <symbol>None</symbol>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>SyntaxError</errorname>
+ <classname>SyntaxError</classname>
</term>
<listitem>
<para>
<title>Description</title>
<para>
<function>get_deftty()</function> returns the current default
- debug terminal specification, or None if the environment variables should
+ debug terminal specification, or <symbol>None</symbol> if the environment variables should
be used. Environment variables will not be looked up.
</para>
</refsect1>
</refmeta>
<refnamediv>
<refname>set_deftty</refname>
- <refpurpose>set default debug terminal specification [DV]</refpurpose>
+ <refpurpose>set default connection debug terminal specification [DV]</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
-set_deftty(<replaceable>terminal</replaceable>)
+set_deftty(<parameter>terminal</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-SET-DEFTTY-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>terminal</replaceable>
+ <parameter>terminal</parameter>
</term>
<listitem>
- <para>New default debug terminal (string/None).</para>
+ <para>New default debug terminal (string/<symbol>None</symbol>).</para>
</listitem>
</varlistentry>
</variablelist>
<variablelist>
<varlistentry>
<term>
- string or None
+ string or <symbol>None</symbol>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
<title>Description</title>
<para>
<function>set_deftty()</function> sets the default terminal value
- for new connections. If None is supplied as parameter, environment
+ for new connections. If <symbol>None</symbol> is supplied as parameter, environment
variables will be used in future connections. It returns the
previous setting for default terminal.
</para>
<variablelist>
<varlistentry>
<term>
- string or None
+ string or <symbol>None</symbol>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>SyntaxError</errorname>
+ <classname>SyntaxError</classname>
</term>
<listitem>
<para>
<title>Description</title>
<para>
<function>get_defbase()</function> returns the current default
- database name specification, or None if the environment variables should
+ database name specification, or <symbol>None</symbol> if the environment variables should
be used. Environment variables will not be looked up.
</para>
</refsect1>
<refsynopsisdiv>
<synopsis>
-set_defbase(<replaceable>database</replaceable>)
+set_defbase(<parameter>database</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-SET-DEFBASE-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>database</replaceable>
+ <parameter>database</parameter>
</term>
<listitem>
- <para>New default database name (string/None).</para>
+ <para>New default database name (string/<symbol>None</symbol>).</para>
</listitem>
</varlistentry>
</variablelist>
<variablelist>
<varlistentry>
<term>
- string or None
+ string or <symbol>None</symbol>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
<title>Description</title>
<para>
<function>set_defbase()</function> sets the default database name
- for new connections. If None is supplied as parameter, environment
+ for new connections. If <symbol>None</symbol> is supplied as parameter, environment
variables will be used in future connections. It returns the
previous setting for default database name.
</para>
<sect1 id="pygresql-pg-pgobject">
- <title>Connection object: <classname>pgobject</classname></title>
+ <title>Connection Object: <classname>pgobject</classname></title>
<para>
This object handles a connection to the
Some methods give direct access to the connection socket. They are
specified by the tag [DA]. <emphasis>Do not use them unless you
really know what you are doing.</emphasis> If you prefer disabling
- them, set the <literal>-DNO_DIRECT</literal> option in the
- <productname>Python</productname> <filename>Setup</filename> file.
+ them, set the <option>-DNO_DIRECT</option> option in the
+ <application>Python</application> <filename>Setup</filename> file.
</para>
<para>
Some other methods give access to large objects. if you want to
forbid access to these from the module, set the
- <literal>-DNO_LARGE</literal> option in the
- <productname>Python</productname> <filename>Setup</filename> file.
+ <option>-DNO_LARGE</option> option in the
+ <application>Python</application> <filename>Setup</filename> file.
These methods are specified by the tag [LO].
</para>
<para>
- Every <literal>pgobject</literal> defines a set of read-only
+ Every <classname>pgobject</classname> defines a set of read-only
attributes that describe the connection and its status. These
attributes are:
<term>status</term>
<listitem>
<para>
- the status of the connection (integer: 1 - OK, 0 - BAD)
+ the status of the connection (integer: 1 - OK, 0 - bad)
</para>
</listitem>
</varlistentry>
</refmeta>
<refnamediv>
<refname>query</refname>
- <refpurpose>executes a SQL command</refpurpose>
+ <refpurpose>execute a SQL command</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
-query(<replaceable>command</replaceable>)
+query(<parameter>command</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-QUERY-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>command</replaceable>
+ <parameter>command</parameter>
</term>
<listitem>
<para>SQL command (string).</para>
<variablelist>
<varlistentry>
<term>
- pgqueryobject or None
+ <classname>pgqueryobject</> or <symbol>None</symbol>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>ValueError</errorname>
+ <classname>ValueError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
query to the database. If the query is an insert statement, the return
value is the <acronym>OID</acronym> of the newly inserted row.
If it is otherwise a query that does not return a result
- (i.e., is not a some kind of <literal>SELECT</literal> statement), it returns None.
- Otherwise, it returns a <literal>pgqueryobject</literal> that can be accessed via the
+ (i.e., is not a some kind of <literal>SELECT</literal> statement), it returns <symbol>None</symbol>.
+ Otherwise, it returns a <classname>pgqueryobject</classname> that can be accessed via the
<function>getresult()</function> or <function>dictresult()</function>
methods or simply printed.
</para>
</refmeta>
<refnamediv>
<refname>reset</refname>
- <refpurpose>resets the connection</refpurpose>
+ <refpurpose>reset the connection</refpurpose>
</refnamediv>
<refsynopsisdiv>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
</refmeta>
<refnamediv>
<refname>fileno</refname>
- <refpurpose>returns the socket used to connect to the database</refpurpose>
+ <refpurpose>return the socket used to connect to the database</refpurpose>
</refnamediv>
<refsynopsisdiv>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
</refmeta>
<refnamediv>
<refname>getnotify</refname>
- <refpurpose>gets the last notify from the server</refpurpose>
+ <refpurpose>get the last notify from the server</refpurpose>
</refnamediv>
<refsynopsisdiv>
<variablelist>
<varlistentry>
<term>
- tuple, None
+ tuple, <symbol>None</symbol>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
<title>Description</title>
<para>
<function>getnotify()</function> method tries to get a notify from
- the server (from the <literal>SQL</literal> statement <literal>NOTIFY</literal>).
- If the server returns no notify, the methods returns None.
+ the server (from the SQL statement <literal>NOTIFY</literal>).
+ If the server returns no notify, the methods returns <symbol>None</symbol>.
Otherwise, it returns a tuple (couple) <literal>(relname, pid)</literal>,
where <literal>relname</literal> is the name of the notify and <literal>pid</literal>
the process id of the connection that triggered the notify.
- Remember to do a listen query first otherwise getnotify will always return None.
+ Remember to do a listen query first otherwise <function>getnotify</> will always return <symbol>None</symbol>.
</para>
</refsect1>
</refmeta>
<refnamediv>
<refname>inserttable</refname>
- <refpurpose>inserts a list into a table</refpurpose>
+ <refpurpose>insert a list into a table</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
-inserttable(<replaceable>table</replaceable>, <replaceable>values</replaceable>)
+inserttable(<parameter>table</parameter>, <parameter>values</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-INSERTTABLE-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>table</replaceable>
+ <parameter>table</parameter>
</term>
<listitem>
<para>The table name (string).</para>
</varlistentry>
<varlistentry>
<term>
- <replaceable>values</replaceable>
+ <parameter>values</parameter>
</term>
<listitem>
<para>The list of rows values to insert (list).</para>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
tuples/lists that define the values for each inserted row. The
rows values may contain string, integer, long or double (real)
values. <emphasis>Be very careful:</emphasis> this method
- does not typecheck the fields according to the table
+ does not type-check the fields according to the table
definition; it just look whether or not it knows how to handle
such types.
</para>
</refmeta>
<refnamediv>
<refname>putline</refname>
- <refpurpose>writes a line to the server socket [DA]</refpurpose>
+ <refpurpose>write a line to the server socket [DA]</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
-putline(<replaceable>line</replaceable>)
+putline(<parameter>line</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-PUTLINE-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>line</replaceable>
+ <parameter>line</parameter>
</term>
<listitem>
<para>Line to be written (string).</para>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
</refmeta>
<refnamediv>
<refname>getline</refname>
- <refpurpose>gets a line from server socket [DA]</refpurpose>
+ <refpurpose>get a line from server socket [DA]</refpurpose>
</refnamediv>
<refsynopsisdiv>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
</refmeta>
<refnamediv>
<refname>endcopy</refname>
- <refpurpose>synchronizes client and server [DA]</refpurpose>
+ <refpurpose>synchronize client and server [DA]</refpurpose>
</refnamediv>
<refsynopsisdiv>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
</refmeta>
<refnamediv>
<refname>locreate</refname>
- <refpurpose>creates of large object in the database [LO]</refpurpose>
+ <refpurpose>create a large object in the database [LO]</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
-locreate(<replaceable>mode</replaceable>)
+locreate(<parameter>mode</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-LOCREATE-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>mode</replaceable>
+ <parameter>mode</parameter>
</term>
<listitem>
<para>Large object create mode.</para>
<variablelist>
<varlistentry>
<term>
- pglarge
+ <classname>pglarge</>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
<para>
<function>locreate()</function> method creates a large object in the database.
The mode can be defined by OR-ing the constants defined in the pg module
- (<literal>INV_READ and INV_WRITE</literal>).
+ (<literal>INV_READ</literal> and <literal>INV_WRITE</literal>).
</para>
</refsect1>
</refmeta>
<refnamediv>
<refname>getlo</refname>
- <refpurpose>builds a large object from given <literal>oid</literal> [LO]</refpurpose>
+ <refpurpose>build a large object from given OID [LO]</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
-getlo(<replaceable>oid</replaceable>)
+getlo(<parameter>oid</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-GETLO-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>oid</replaceable>
+ <parameter>oid</parameter>
</term>
<listitem>
- <para><literal>OID</literal> of the existing large object (integer).</para>
+ <para>OID of the existing large object (integer).</para>
</listitem>
</varlistentry>
</variablelist>
<variablelist>
<varlistentry>
<term>
- pglarge
+ <classname>pglarge</>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
<para>
<function>getlo()</function> method allows to reuse a formerly
created large object through the <classname>pglarge</classname> interface, providing
- the user have its <literal>oid</literal>.
+ the user has its OID.
</para>
</refsect1>
</refmeta>
<refnamediv>
<refname>loimport</refname>
- <refpurpose>import
s a file to a <productname>PostgreSQL</productname> large object [LO]</refpurpose>
+ <refpurpose>import a file to a <productname>PostgreSQL</productname> large object [LO]</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
-loimport(<replaceable>filename</replaceable>)
+loimport(<parameter>filename</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-LOIMPORT-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>filename</replaceable>
+ <parameter>filename</parameter>
</term>
<listitem>
<para>The name of the file to be imported (string).</para>
<variablelist>
<varlistentry>
<term>
- pglarge
+ <classname>pglarge</>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
<sect1 id="pygresql-pg-DB">
- <title>Database wrapper class: <classname>DB</classname></title>
+ <title>Database Wrapper Class: <classname>DB</classname></title>
<para>
<classname>pg</classname> module contains a class called
</refmeta>
<refnamediv>
<refname>pkey</refname>
- <refpurpose>returns the primary key of a table</refpurpose>
+ <refpurpose>return the primary key of a table</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
-pkey(<replaceable>table</replaceable>)
+pkey(<parameter>table</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-DB-PKEY-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>table</replaceable>
+ <parameter>table</parameter>
</term>
<listitem>
<para>
</refmeta>
<refnamediv>
<refname>get_attnames</refname>
- <refpurpose>returns the attribute names of a table</refpurpose>
+ <refpurpose>return the attribute names of a table</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
-get_attnames(<replaceable>table</replaceable>)
+get_attnames(<parameter>table</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-DB-GET-ATTNAMES-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>table</replaceable>
+ <parameter>table</parameter>
</term>
<listitem>
<para>
<refsynopsisdiv>
<synopsis>
-get(<replaceable>table</replaceable>, <replaceable>arg</replaceable>, <optional><replaceable>keyname</replaceable></optional>)
+get(<parameter>table</parameter>, <parameter>arg</parameter>, <optional><parameter>keyname</parameter></optional>)
</synopsis>
<refsect2 id="R2-PYGRESQL-DB-GET-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>table</replaceable>
+ <parameter>table</parameter>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <replaceable>arg</replaceable>
+ <parameter>arg</parameter>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <optional><replaceable>keyname</replaceable></optional>
+ <optional><parameter>keyname</parameter></optional>
</term>
<listitem>
<para>
<title>Description</title>
<para>
This method is the basic mechanism to get a single row. It assumes
- that the key specifies a unique row. If keyname is not specified
- then the primary key for the table is used. If arg is a dictionary
+ that the key specifies a unique row. If <parameter>keyname</> is not specified
+ then the primary key for the table is used. If <parameter>arg</> is a dictionary
then the value for the key is taken from it and it is modified to
include the new values, replacing existing values where necessary.
- The oid is also put into the dictionary but in order to allow the
+ The OID is also put into the dictionary but in order to allow the
caller to work with multiple tables, the attribute name is munged
to make it unique. It consists of the string <literal>oid_</literal> followed by
the name of the table.
<refsynopsisdiv>
<synopsis>
-insert(<replaceable>table</replaceable>, <replaceable>a</replaceable>)
+insert(<parameter>table</parameter>, <parameter>a</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-DB-INSERT-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>table</replaceable>
+ <parameter>table</parameter>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <replaceable>a</replaceable>
+ <parameter>a</parameter>
</term>
<listitem>
<para>
values from the database. This causes the dictionary to be updated
with values that are modified by rules, triggers, etc.
</para>
+
+ <para>
+ Due to the way that this function works you will find inserts
+ taking longer and longer as your table gets bigger. To
+ overcome this problem simply add an index onto the OID of any
+ table that you think may get large over time.
+ </para>
</refsect1>
</refentry>
<refsynopsisdiv>
<synopsis>
-update(<replaceable>table</replaceable>, <replaceable>a</replaceable>)
+update(<parameter>table</parameter>, <parameter>a</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-DB-UPDATE-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>table</replaceable>
+ <parameter>table</parameter>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <replaceable>a</replaceable>
+ <parameter>a</parameter>
</term>
<listitem>
<para>
<refsynopsisdiv>
<synopsis>
-clear(<replaceable>table</replaceable>, <optional><replaceable>a</replaceable></optional>)
+clear(<parameter>table</parameter>, <optional><parameter>a</parameter></optional>)
</synopsis>
<refsect2 id="R2-PYGRESQL-DB-CLEAR-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>table</replaceable>
+ <parameter>table</parameter>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <optional><replaceable>a</replaceable></optional>
+ <optional><parameter>a</parameter></optional>
</term>
<listitem>
<para>
</refmeta>
<refnamediv>
<refname>delete</refname>
- <refpurpose>deletes the row from a table</refpurpose>
+ <refpurpose>delete a row from a table</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
-delete(<replaceable>table</replaceable>, <optional><replaceable>a</replaceable></optional>)
+delete(<parameter>table</parameter>, <optional><parameter>a</parameter></optional>)
</synopsis>
<refsect2 id="R2-PYGRESQL-DB-DELETE-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>table</replaceable>
+ <parameter>table</parameter>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <optional><replaceable>a</replaceable></optional>
+ <optional><parameter>a</parameter></optional>
</term>
<listitem>
<para>
<!-- ********************************************************** -->
<sect1 id="pygresql-pg-pgqueryobject">
- <title>Query result object: <literal>pgqueryobject</literal></title>
+ <title>Query Result Object: <classname>pgqueryobject</classname></title>
<!-- ********************************************************** -->
</refmeta>
<refnamediv>
<refname>getresult</refname>
- <refpurpose>gets the values returned by the query</refpurpose>
+ <refpurpose>get the values returned by the query</refpurpose>
</refnamediv>
<refsynopsisdiv>
<variablelist>
<varlistentry>
<term>
- <errorname>SyntaxError</errorname>
+ <classname>SyntaxError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
</refmeta>
<refnamediv>
<refname>dictresult</refname>
- <refpurpose>like getresult but returns a list of dictionaries</refpurpose>
+ <refpurpose>get the values returned by the query as a list of dictionaries</refpurpose>
</refnamediv>
<refsynopsisdiv>
<variablelist>
<varlistentry>
<term>
- <errorname>SyntaxError</errorname>
+ <classname>SyntaxError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
</refmeta>
<refnamediv>
<refname>listfields</refname>
- <refpurpose>lists the fields names of the query result</refpurpose>
+ <refpurpose>list the fields names of the query result</refpurpose>
</refnamediv>
<refsynopsisdiv>
<variablelist>
<varlistentry>
<term>
- <errorname>SyntaxError</errorname>
+ <classname>SyntaxError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
</refmeta>
<refnamediv>
<refname>fieldname</refname>
- <refpurpose>field number-name conversion</refpurpose>
+ <refpurpose>get field name by number</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
-fieldname(<replaceable>i</replaceable>)
+fieldname(<parameter>i</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-PGQUERYOBJECT-FIELDNAME-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>i</replaceable>
+ <parameter>i</parameter>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <replaceable>ValueError</replaceable>
+ <classname>ValueError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
</refmeta>
<refnamediv>
<refname>fieldnum</refname>
- <refpurpose>field name-number conversion</refpurpose>
+ <refpurpose>get field number by name</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
-fieldnum(<replaceable>name</replaceable>)
+fieldnum(<parameter>name</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-PGQUERYOBJECT-FIELDNUM-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>name</replaceable>
+ <parameter>name</parameter>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <replaceable>ValueError</replaceable>
+ <classname>ValueError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
</refmeta>
<refnamediv>
<refname>ntuples</refname>
- <refpurpose>returns the number of tuples in query object</refpurpose>
+ <refpurpose>return the number of tuples in query object</refpurpose>
</refnamediv>
<refsynopsisdiv>
<variablelist>
<varlistentry>
<term>
- <errorname>SyntaxError</errorname>
+ <classname>SyntaxError</classname>
</term>
<listitem>
<para>
<para>
This object handles all the request concerning a
<productname>PostgreSQL</productname> large object. It embeds and
- hides all the <quote>recurrent</quote> variables (object oid and
+ hides all the <quote>recurrent</quote> variables (object OID and
connection), exactly in the same way
<classname>pgobject</classname>s do, thus only keeping significant
parameters in function calls. It keeps a reference to the <classname>pgobject</classname>
<variablelist>
<varlistentry>
- <term>oid</term>
+ <term><structfield>oid</></term>
<listitem>
<para>
- the oid associated with the object
+ the OID associated with the object
</para>
</listitem>
</varlistentry>
<varlistentry>
- <term>pgcnx</term>
+ <term><structfield>pgcnx</></term>
<listitem>
<para>
the <classname>pgobject</classname> associated with the object
</varlistentry>
<varlistentry>
- <term>error</term>
+ <term><structfield>error</></term>
<listitem>
<para>
the last warning/error message of the connection
</varlistentry>
</variablelist>
- <note>
- <title>Be careful</title>
-
+ <important>
<para>
In multithreaded environments, <structfield>error</structfield>
may be modified by another thread using the same
- <classname>pgobject</classname>. Remember these object are
- shared, not duplicated; you should provide some locking to be
- able if you want to check this. The oid attribute is very
- interesting because it allow you reuse the oid later, creating
- the <classname>pglarge</classname> object with a <classname>pgobject</classname>
+ <classname>pgobject</classname>. Remember that these object are
+ shared, not duplicated; you should provide some locking if you
+ want to check for the error message in this situation. The OID
+ attribute is very interesting because it allow you to reuse the
+ OID later, creating the <classname>pglarge</classname> object
+ with a <classname>pgobject</classname>
<function>getlo()</function> method call.
</para>
- </note>
+ </important>
</para>
<para>
</refmeta>
<refnamediv>
<refname>open</refname>
- <refpurpose>opens a large object</refpurpose>
+ <refpurpose>open a large object</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
-open(<replaceable>mode</replaceable>)
+open(<parameter>mode</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-PGLARGEOBJECT-OPEN-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>mode</replaceable>
+ <parameter>mode</parameter>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>IOError</errorname>
+ <classname>IOError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
<title>Description</title>
<para>
<function>open()</function> method opens a large object for reading/writing,
- in the same way than the <acronym>UNIX</acronym> <function>open()</function>
+ in the same way than the Unix <function>open()</function>
function. The mode value can be obtained by OR-ing the constants defined in
- the pg module (<literal>INV_READ, INV_WRITE</literal>).
+ the pg module (<literal>INV_READ</literal>, <literal>INV_WRITE</literal>).
</para>
</refsect1>
</refmeta>
<refnamediv>
<refname>close</refname>
- <refpurpose>closes the large object</refpurpose>
+ <refpurpose>close the large object</refpurpose>
</refnamediv>
<refsynopsisdiv>
<variablelist>
<varlistentry>
<term>
- <errorname>SyntaxError</errorname>
+ <classname>SyntaxError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>IOError</errorname>
+ <classname>IOError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
<title>Description</title>
<para>
<function>close()</function> method closes previously opened large object,
- in the same way than the <acronym>UNIX</acronym> <function>close()</function> function.
+ in the same way than the Unix <function>close()</function> function.
</para>
</refsect1>
</refmeta>
<refnamediv>
<refname>read</refname>
- <refpurpose>reads from the large object</refpurpose>
+ <refpurpose>read from the large object</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
-read(<replaceable>size</replaceable>)
+read(<parameter>size</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-PGLARGEOBJECT-READ-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>size</replaceable>
+ <parameter>size</parameter>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>IOError</errorname>
+ <classname>IOError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
</refmeta>
<refnamediv>
<refname>write</refname>
- <refpurpose>writes to the large object</refpurpose>
+ <refpurpose>write to the large object</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
-write(<replaceable>string</replaceable>)
+write(<parameter>string</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-PGLARGEOBJECT-WRITE-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>string</replaceable>
+ <parameter>string</parameter>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>IOError</errorname>
+ <classname>IOError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
<refsynopsisdiv>
<synopsis>
-seek(<replaceable>offset</replaceable>, <replaceable>whence</replaceable>)
+seek(<parameter>offset</parameter>, <parameter>whence</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-PGLARGEOBJECT-SEEK-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>offset</replaceable>
+ <parameter>offset</parameter>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <replaceable>whence</replaceable>
+ <parameter>whence</parameter>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>IOError</errorname>
+ <classname>IOError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
<para>
<function>seek()</function> method allows to move the cursor position
in the large object. The whence parameter can be obtained by OR-ing the constants defined in the
- <literal>pg</literal> module (<literal>SEEK_SET, SEEK_CUR, SEEK_END</literal>).
+ <literal>pg</literal> module (<literal>SEEK_SET</>, <>SEEK_CUR</>, <>SEEK_END</literal>).
</para>
</refsect1>
</refmeta>
<refnamediv>
<refname>tell</refname>
- <refpurpose>returns current position in the large object</refpurpose>
+ <refpurpose>return current position in the large object</refpurpose>
</refnamediv>
<refsynopsisdiv>
<variablelist>
<varlistentry>
<term>
- <errorname>SyntaxError</errorname>
+ <classname>SyntaxError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>IOError</errorname>
+ <classname>IOError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
</refmeta>
<refnamediv>
<refname>unlink</refname>
- <refpurpose>deletes the large object</refpurpose>
+ <refpurpose>delete the large object</refpurpose>
</refnamediv>
<refsynopsisdiv>
<variablelist>
<varlistentry>
<term>
- <errorname>SyntaxError</errorname>
+ <classname>SyntaxError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>IOError</errorname>
+ <classname>IOError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
</refmeta>
<refnamediv>
<refname>size</refname>
- <refpurpose>gives the large object size</refpurpose>
+ <refpurpose>return the large object size</refpurpose>
</refnamediv>
<refsynopsisdiv>
<variablelist>
<varlistentry>
<term>
- <errorname>SyntaxError</errorname>
+ <classname>SyntaxError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>IOError</errorname>
+ <classname>IOError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
<para>
<function>size()</function> method allows to get the size of
the large object. It was implemented because this function
- is very useful for a WWW interfaced database.
- Currently the large object needs to be opened.
+ is very useful for a WWW-interfaced database.
+ Currently, the large object needs to be opened first.
</para>
</refsect1>
</refmeta>
<refnamediv>
<refname>export</refname>
- <refpurpose>saves the large object to file</refpurpose>
+ <refpurpose>save the large object to file</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
-export(<replaceable>filename</replaceable>)
+export(<parameter>filename</parameter>)
</synopsis>
<refsect2 id="R2-PYGRESQL-PGLARGEOBJECT-EXPORT-1">
<variablelist>
<varlistentry>
<term>
- <replaceable>filename</replaceable>
+ <parameter>filename</parameter>
</term>
<listitem>
<para>
<variablelist>
<varlistentry>
<term>
- <errorname>TypeError</errorname>
+ <classname>TypeError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>IOError</errorname>
+ <classname>IOError</classname>
</term>
<listitem>
<para>
</varlistentry>
<varlistentry>
<term>
- <errorname>pg.error</errorname>
+ <classname>pg.error</classname>
</term>
<listitem>
<para>
</sect1>
-
- <sect1 id="pygresql-db-api">
- <title><acronym>DB-API</acronym> Interface</title>
-
- <comment>
- This section needs to be written.
- </comment>
-
- <para>
- See <ulink
- url="http://www.python.org/topics/database/DatabaseAPI-2.0.html"
- >http://www.python.org/topics/database/DatabaseAPI-2.0.html</ulink>
- for a description of the <acronym>DB-API</acronym> 2.0.
- </para>
- </sect1>
-
</chapter>
based on the PyGres95 code written by Pascal Andre, andre@chimay.via.ecp.fr.
I changed the version to 2.0 and updated the code for Python 1.5 and
PostgreSQL 6.2.1. While I was at it I upgraded the code to use full ANSI
-style prototypes and changed the order of arguments to connect. The latest
-version of PyGreSQL works with PostgreSQL 7.1.3 and Python 2.1.
+style prototypes and changed the order of arguments to connect.
1.2. Distribution files
you must already have built Python as well as the mxDateTime package
from http://starship.python.net/~lemburg/mxDateTime.html.
-* For Linux installation look at README.linux. If you're on an x86 system
- that uses RPMs, then you can pick up an RPM at
+* For a Linux x86 system that uses RPMs, you can pick up an RPM at
ftp://ftp.druid.net/pub/distrib/pygresql.i386.rpm
* Note that if you are using the DB-API module you must also install
2. Programming information
==========================
-You may either choose to use the old, mature interface provided by the
-'pg' module or else the newer 'pgdb' interface compliant with DB-API 2.0
-specification developed by the Python DB-SIG.
+See main PostgreSQL documentation.
-The remainder of this chapter and the next chapter describe only
-the older 'pg' API. As long as PyGreSQL does not contain a
-description of the DB-API you should read about the API at
-http://www.python.org/topics/database/DatabaseAPI-2.0.html
-A tutorial like introduction to the DB-API can be found at
-http://www2.linuxjournal.com/lj-issues/issue49/2605.html
-
-The 'pg' module defines three objects: the pgobject that handles the connection
-and all the requests to the database, the pglargeobject that handles
-all the accesses to Postgres large objects and pgqueryobject that handles
-query results.
-
-If you want to see a simple example of the use of some of these functions,
-see http://www.druid.net/rides/ where I have a link at the bottom to the
-actual Python code for the page.
-
-2.1. pg module description
-----------------------------
-
-The module defines only a few methods that allow to connect to a database and
-to allow to define "default variables" that override the environment variables
-used by PostgreSQL.
-
-These "default variables" were designed to allow you to handle general
-connection parameters without heavy code in your programs. You can prompt the
-user for a value, put it in the default variable, and forget it, without
-having to modify your environment. The support for default variables can be
-disabled by setting the -DNO_DEF_VAR option in the Python Setup file. Methods
-relative to this are specified by te tag [DV].
-
-All variables are set to None at module initialization, specifying that
-standard environment variables should be used.
-
- 2.1.1. connect - opens a pg connection
- ----------------------------------------
-
- Syntax:
- connect(dbname, host, port, opt, tty, user, passwd)
- Parameters:
- dbname - name of connected database (string/None)
- host - name of the server host (string/None)
- port - port used by the database server (integer/-1)
- opt - connection options (string/None)
- tty - debug terminal (string/None)
- user - PostgreSQL user (string/None)
- passwd - password for user (string/None)
- Return type:
- pgobject - the object handling the connection
- Exceptions raised:
- TypeError - bad argument type, or too many arguments
- SyntaxError - duplicate argument definition
- pg.error - some error occurred during pg connection definition
- (+ all exceptions relative to object allocation)
- Description:
- This method opens a connection to a specified database on a given
- PostgreSQL server. You can use keywords here, as described in the
- Python tutorial;
- the names of the keywords are the name of the parameters given in the
- syntax line. For a precise description of the parameters, please refer to
- the PostgreSQL user manual.
-
- 2.1.2. get_defhost, set_defhost - default server host name handling [DV]
- ------------------------------------------------------------------------
-
- Syntax: get_defhost()
- Parameters:
- none
- Return type:
- string, None - default host specification
- Exceptions raised:
- SyntaxError - too many arguments
- Description:
- This method returns the current default host specification, or None if the
- environment variables should be used. Environment variables won't be looked
- up.
-
- Syntax: set_defhost(host)
- Parameters:
- host - new default host (string/None)
- Return type:
- string, None - previous default host specification
- Exceptions raised:
- TypeError - bad argument type, or too many arguments
- Description:
- This methods sets the default host value for new connections. If None is
- supplied as parameter, environment variables will be used in future
- connections. It returns the previous setting for default host.
-
- 2.1.3. get_defport, set_defport - default server port handling [DV]
- -------------------------------------------------------------------
-
- Syntax: get_defport()
- Parameters: none
- Return type:
- integer, None - default port specification
- Exceptions raised:
- SyntaxError - too many arguments
- Description:
- This method returns the current default port specification, or None if
- the environment variables should be used. Environment variables won't
- be looked up.
-
- Syntax: set_defport(port)
- Parameters:
- port - new default port (integer/-1)
- Return type:
- integer, None - previous default port specification
- Description:
- This methods sets the default port value for new connections. If -1 is
- supplied as parameter, environment variables will be used in future
- connections. It returns the previous setting for default port.
-
- 2.1.4. get_defopt, set_defopt - default connection options handling [DV]
- ------------------------------------------------------------------------
-
- Syntax: get_defopt()
- Parameters: none
- Return type:
- string, None - default options specification
- Exceptions raised:
- SyntaxError - too many arguments
- Description:
- This method returns the current default connection options specification,
- or None if the environment variables should be used. Environment variables
- won't be looked up.
-
- Syntax: set_defopt(options)
- Parameters:
- options - new default connection options (string/None)
- Return type:
- string, None - previous default options specification
- Exceptions raised:
- TypeError - bad argument type, or too many arguments
- Description:
- This methods sets the default connection options value for new connections.
- If None is supplied as parameter, environment variables will be used in
- future connections. It returns the previous setting for default options.
-
- 2.1.5. get_deftty, set_deftty - default connection debug tty handling [DV]
- --------------------------------------------------------------------------
-
- Syntax: get_deftty()
- Parameters: none
- Return type:
- string, None - default debug terminal specification
- Exceptions raised:
- SyntaxError - too many arguments
- Description:
- This method returns the current default debug terminal specification, or
- None if the environment variables should be used. Environment variables
- won't be looked up.
-
- Syntax: set_deftty(terminal)
- Parameters:
- terminal - new default debug terminal (string/None)
- Return type:
- string, None - previous default debug terminal specification
- Exceptions raised:
- TypeError - bad argument type, or too many arguments
- Description:
- This methods sets the default debug terminal value for new connections. If
- None is supplied as parameter, environment variables will be used in future
- connections. It returns the previous setting for default terminal.
-
- 2.1.6. get_defbase, set_defbase - default database name handling [DV]
- ---------------------------------------------------------------------
-
- Syntax: get_defbase()
- Parameters: none
- Return type:
- string, None - default database name specification
- Exceptions raised:
- SyntaxError - too many arguments
- Description:
- This method returns the current default database name specification, or
- None if the environment variables should be used. Environment variables
- won't be looked up.
-
- Syntax: set_defbase(base)
- Parameters:
- base - new default base name (string/None)
- Return type:
- string, None - previous default database name specification
- Exceptions raised:
- TypeError - bad argument type, or too many arguments
- Description:
- This method sets the default database name value for new connections. If
- None is supplied as parameter, environment variables will be used in
- future connections. It returns the previous setting for default host.
-
- 2.1.7. Module constants
- -----------------------
-
- Some constants are defined in the module dictionary. They are intended to be
-used as parameters for methods calls. You should refer to PostgreSQL user
-manual for more information about them. These constants are:
-
- - large objects access modes, used by (pgobject.)locreate and
- (pglarge.)open: (pg.)INV_READ, (pg.)INV_WRITE
- - positional flags, used by (pglarge.)seek: (pg.)SEEK_SET,
- (pg.)SEEK_CUR, (pg.)SEEK_END.
- - version and __version__ constants that give the current version.
-
- 2.1.9.
- 2.1.10. Miscellaneous attributes
-
- The following methods return information about the current connection.
-
- -
-2.2. pgobject description
----------------------------
-
- This object handle a connection to a PostgreSQL database. It embeds and
-hides all the parameters that define this connection, thus just leaving really
-significant parameters in function calls.
- Some methods give direct access to the connection socket. They are specified
-by the tag [DA]. DO NOT USE THEM UNLESS YOU REALLY KNOW WHAT YOU ARE DOING. If
-you prefer disabling them, set the -DNO_DIRECT option in the Python Setup file.
- Some other methods give access to large objects (refer to PostgreSQL user
-manual for more information about these). if you want to forbid access to these
-from the module, set the -DNO_LARGE option in the Python Setup file. These
-methods are specified by the tag [LO].
-
- 2.2.1. query - executes a SQL command string
- --------------------------------------------
-
- Syntax: query(command)
- Parameters:
- command - SQL command (string)
- Return type:
- pgqueryobject, None - result values
- Exceptions raised:
- TypeError - bad argument type, or too many arguments.
- ValueError - empty SQL query
- pg.error - error during query processing, or invalid connection
- Description:
- This method simply sends a SQL query to the database. If the query is
- an insert statement, the return value is the OID of the newly
- inserted row. If it is otherwise a query that does not return a result
- (ie. is not a some kind of SELECT statement), it returns None.
- Otherwise, it returns a pgqueryobject that can be accessed via the
- getresult or dictresult method or simply printed.
-
- pgqueryobject methods
- ---------------------
-
- 2.2.1.1. getresult - gets the values returned by the query
- -------------------------------------------------------------
-
- Syntax: getresult()
- Parameters: none
- Return type:
- list - result values
- Exceptions raised:
- SyntaxError - too many parameters
- pg.error - invalid previous result
- Description:
- This method returns the list of the values returned by the query.
- More information about this result may be accessed using listfields,
- fieldname and fieldnum methods.
-
- 2.2.1.2. dictresult - like getresult but returns list of dictionaries
- ---------------------------------------------------------------------
-
- Syntax: dictresult()
- Parameters: none
- Return type:
- list - result values as a dictionary
- Exceptions raised:
- SyntaxError - too many parameters
- pg.error - invalid previous result
- Description:
- This method returns the list of the values returned by the query
- with each tuple returned as a dictionary with the field names
- used as the dictionary index.
-
-
- 2.2.1.3. listfields - lists the fields names of the previous query result
- -----------------------------------------------------------------------
-
- Syntax: listfields()
- Parameters: none
- Return type:
- list - fields names
- Exceptions raised:
- SyntaxError - too many parameters
- pg.error - invalid previous result, or invalid connection
- Description:
- This method returns the list of names of the fields defined for the
- query result. The fields are in the same order as the result values.
-
- 2.2.1.4. fieldname, fieldnum - field name-number conversion
- ---------------------------------------------------------
-
- Syntax: fieldname(i)
- Parameters:
- i - field number (integer)
- Return type:
- string - field name
- Exceptions raised:
- TypeError - bad parameter type, or too many parameters
- ValueError - invalid field number
- pg.error - invalid previous result, or invalid connection
- Description:
- This method allows to find a field name from its rank number. It can be
- useful for displaying a result. The fields are in the same order as the
- result values.
-
- Syntax: fieldnum(name)
- Parameters:
- name - field name (string)
- Return type:
- integer - field number
- Exceptions raised:
- TypeError - bad parameter type, or too many parameters
- ValueError - unknown field name
- pg.error - invalid previous result, or invalid connection
- Description:
- This method returns a field number from its name. It can be used to
- build a function that converts result list strings to their correct
- type, using a hardcoded table definition. The number returned is the
- field rank in the result values list.
-
- 2.2.1.5 ntuples - return number of tuples in query object
- ---------------------------------------------------------
-
- Syntax: ntuples()
- Parameters: None
- Return type: integer
- Description:
- This method returns the number of tuples found in a query.
-
-
- 2.2.2. reset - resets the connection
- ------------------------------------
-
- Syntax: reset()
- Parameters: None
- Return type: None
- Exceptions raised:
- TypeError - too many (any) arguments
- Description:
- This method resets the current database.
-
-
- 2.2.3. close - close the database connection
- --------------------------------------------
-
- Syntax: close()
- Parameters: none
- Return type: None
- Exceptions raised:
- TypeError - too many (any) arguments
- Description:
- This method closes the database connection. The connection will
- be closed in any case when the connection is deleted but this
- allows you to explicitly close it. It is mainly here to allow
- the DB-SIG API wrapper to implement a close function.
-
-
- 2.2.4. fileno - returns the socket used to connect to the database
- ------------------------------------------------------------------
-
- Syntax: fileno()
- Parameters: none
- Exceptions raised:
- TypeError - too many (any) arguments
- Description:
- This method returns the underlying socket id used to connect
- to the database. This is useful for use in select calls, etc.
- Note: This function depends on having a recent version of the
- database. See "-DNO_PQSOCKET" described above.
-
-
- 2.2.5. getnotify - gets the last notify from the server
- -------------------------------------------------------
-
- Syntax: getnotify()
- Parameters: none
- Return type:
- tuple, None - last notify from server
- Exceptions raised:
- SyntaxError - too many parameters
- pg.error - invalid connection
- Description:
- This methods try to get a notify from the server (from the SQL statement
- NOTIFY). If the server returns no notify, the methods returns None.
- Otherwise, it returns a tuple (couple) (relname, pid), where relname is the
- name of the notify and pid the process id of the connection that triggered
- the notify. Remember to do a listen query first otherwise getnotify
- will always return None.
-
- 2.2.6. inserttable - insert a list into a table
- -----------------------------------------------
-
- Syntax: inserttable(table, values)
- Parameters:
- table - the table name (string)
- values - list of rows values (list)
- Return type:
- None
- Exception raised:
- pg.error - invalid connection
- TypeError - bad argument type, or too many arguments
- Description:
- This method allow to quickly insert large blocks of data in a table: it
- inserts the whole values list into the given table. The list is a list of
- tuples/lists that define the values for each inserted row. The rows values
- may contain string, integer, long or double (real) values.
- BE VERY CAREFUL: this method doesn't typecheck the fields according to the
- table definition; it just look whether or not it knows how to handle such
- types.
-
- 2.2.7. putline - writes a line to the server socket [DA]
- --------------------------------------------------------
-
- Syntax: putline(line)
- Parameters:
- line - line to be written (string)
- Return type:
- None
- Exceptions raised:
- pg.error - invalid connection
- TypeError - bad parameter type, or too many parameters
- Description:
- This method allows to directly write a string to the server socket.
-
- 2.2.8. getline - gets a line from server socket [DA]
- ----------------------------------------------------
-
- Syntax: getline()
- Parameters: none
- Return type:
- string - the line read
- Exceptions raised:
- pg.error - invalid connection
- SyntaxError - too many parameters
- Description:
- This method allows to directly read a string from the server socket.
-
- 2.2.9. endcopy - synchronizes client and server [DA]
- ----------------------------------------------------
-
- Syntax: endcopy()
- Parameters: none
- Return type:
- None
- Exceptions raised:
- pg.error - invalid connection
- SyntaxError - too many parameters
- Description:
- The use of direct access methods may desynchonize client and server. This
- method ensure that client and server will be synchronized.
-
- 2.2.10. locreate - creates of large object in the database [LO]
- ---------------------------------------------------------------
-
- Syntax: locreate(mode)
- Parameters:
- mode - large object create mode
- Return type:
- pglarge - object handling the postgres large object
- Exceptions raised:
- pg.error - invalid connection, or creation error
- TypeError - bad parameter type, or too many parameters
- Description:
- This method creates a large object in the database. The mode can be defined
- by OR-ing the constants defined in the pg module (INV_READ, INV_WRITE and
- INV_ARCHIVE). Please refer to PostgreSQL user manual for a description of
- the mode values.
-
- 2.2.11. getlo - builds a large object from given oid [LO]
- ---------------------------------------------------------
-
- Syntax: getlo(oid)
- Parameters:
- oid - oid of the existing large object (integer)
- Return type:
- pglarge - object handling the postgres large object
- Exceptions raised:
- pg.error - invalid connection
- TypeError - bad parameter type, or too many parameters
- ValueError - bad oid value (0 is invalid_oid)
- Description:
- This method allows to reuse a formerly created large object through the
- pglarge interface, providing the user have its oid.
-
- 2.2.12. loimport - import a file to a postgres large object [LO]
- ----------------------------------------------------------------
-
- Syntax: loimport(name)
- Parameters:
- name - the name of the file to be imported (string)
- Return type:
- pglarge - object handling the postgres large object
- Exceptions raised:
- pg.error - invalid connection, or error during file import
- TypeError - bad argument type, or too many arguments
- Description:
- This methods allows to create large objects in a very simple way. You just
- give the name of a file containing the data to be use.
-
- 2.2.13. pgobject attributes
- -----------------------------
-
- Every pgobject defines a set of read-only attributes that describe the
-connection and its status. These attributes are:
- host - the hostname of the server (string)
- port - the port of the server (integer)
- db - the selected database (string)
- options - the connection options (string)
- tty - the connection debug terminal (string)
- user - the username on the database system (string)
- status - the status of the connection (integer: 1 - OK, 0 - BAD)
- error - the last warning/error message from the server (string)
-
-2.3. pglarge description
---------------------------
-
- This object handles all the request concerning a postgres large object. It
-embeds and hides all the 'recurrent' variables (object oid and connection),
-exactly in the same way pgobjects do, thus only keeping significant
-parameters in function calls. It keeps a reference to the pgobject used for
-its creation, sending requests though with its parameters. Any modification but
-dereferencing the pgobject will thus affect the pglarge object.
-Dereferencing the initial pgobject is not a problem since Python won't
-deallocate it before the large object dereference it.
- All functions return a generic error message on call error, whatever the
-exact error was. The 'error' attribute of the object allow to get the exact
-error message.
-
- 2.3.1. open - opens a large object
- ----------------------------------
-
- Syntax: open(mode)
- Parameters:
- mode - open mode definition (integer)
- Return type:
- None
- Exceptions raised:
- pg.error - invalid connection
- TypeError - bad parameter type, or too many parameters
- IOError - already opened object, or open error
- Description:
- This method opens a large object for reading/writing, in the same way than
- the UNIX open() function. The mode value can be obtained by OR-ing the
- constants defined in the pgmodule (INV_READ, INV_WRITE).
-
- 2.3.2. close - closes a large object
- ------------------------------------
-
- Syntax: close()
- Parameters: none
- Return type:
- None
- Exceptions raised:
- pg.error - invalid connection
- SyntaxError - too many parameters
- IOError - object is not opened, or close error
- Description:
- This method closes a previously opened large object, in the same way than
- the UNIX close() function.
-
- 2.3.4. read, write, tell, seek, unlink - file like large object handling
- ------------------------------------------------------------------------
-
- Syntax: read(size)
- Parameters:
- size - maximal size of the buffer to be read
- Return type:
- sized string - the read buffer
- Exceptions raised:
- pg.error - invalid connection or invalid object
- TypeError - bad parameter type, or too many parameters
- IOError - object is not opened, or read error
- Description:
- This function allows to read data from a large object, starting at current
- position.
-
- Syntax: write(string)
- Parameters:
- (sized) string - buffer to be written
- Return type:
- None
- Exceptions raised:
- pg.error - invalid connection or invalid object
- TypeError - bad parameter type, or too many parameters
- IOError - object is not opened, or write error
- Description:
- This function allows to write data to a large object, starting at current
- position.
-
- Syntax: seek(offset, whence)
- Parameters:
- offset - position offset
- whence - positional parameter
- Return type:
- integer - new position in object
- Exception raised:
- pg.error - invalid connection or invalid object
- TypeError - bad parameter type, or too many parameters
- IOError - object is not opened, or seek error
- Description:
- This method allows to move the position cursor in the large object. The
- whence parameter can be obtained by OR-ing the constants defined in the
- pg module (SEEK_SET, SEEK_CUR, SEEK_END).
-
- Syntax: tell()
- Parameters: none
- Return type:
- integer - current position in large object
- Exception raised:
- pg.error - invalid connection or invalid object
- SyntaxError - too many parameters
- IOError - object is not opened, or seek error
- Description:
- This method allows to get the current position in the large object.
-
- Syntax: unlink()
- Parameter: none
- Return type:
- None
- Exception raised:
- pg.error - invalid connection or invalid object
- SyntaxError - too many parameters
- IOError - object is not closed, or unlink error
- Description:
- This methods unlinks (deletes) the postgres large object.
-
- 2.3.5. size - gives the large object size
- -----------------------------------------
-
- Syntax: size()
- Parameters: none
- Return type:
- integer - large object size
- Exceptions raised:
- pg.error - invalid connection or invalid object
- SyntaxError - too many parameters
- IOError - object is not opened, or seek/tell error
- Description:
- This (composite) method allows to get the size of a large object. Currently
- the large object needs to be opened. It was implemented because this
- function is very useful for a WWW interfaced database.
-
- 2.3.6. export - saves a large object to a file
- ----------------------------------------------
-
- Syntax: export(name)
- Parameters:
- name - file to be created
- Return type:
- None
- Exception raised:
- pg.error - invalid connection or invalid object
- TypeError - bad parameter type, or too many parameters
- IOError - object is not closed, or export error
- Description:
- This methods allows to dump the content of a large object in a very simple
- way. The exported file is created on the host of the program, not the
- server host.
-
- 2.3.7. Object attributes
- ------------------------
-
- pglarge objects define a read-only set of attributes that allow to get some
-information about it. These attributes are:
- oid - the oid associated with the object
- pgcnx - the pgobject associated with the object
- error - the last warning/error message of the connection
-BE CAREFUL: in multithreaded environments, 'error' may be modified by another
-thread using the same pgobject. Remember these object are shared, not
-duplicated. You should provide some locking to be able if you want to check
-this.
- The oid attribute is very interesting because it allow you reuse the oid
-later, creating the pglarge object with a pgobject getlo() method call.
-
-
-3. The pg wrapper
-================
-
-The previous functions are wrapped in a module called pg. The module
-has a class called DB. The above functions are also included in the
-name space so it isn't necessary to import both modules. The preferred
-way to use this module is as follows.
-
-import pg
-db = pg.DB(...) # See description of the initialization method below.
-
-The following describes the methods and variables of this class.
-
-
- 3.1. Initialization
- -------------------
- The DB class is initialized with the same arguments as the connect
- method described in section 2. It also initializes a few internal
- variables. The statement 'db = DB()' will open the local database
- with the name of the user just like connect() does.
-
- 3.2. pkey
- ---------
- Syntax:
- pkey(table)
- Parameters:
- table - name of table
- Returns:
- Name of field which is the primary key of the table.
- Description:
- This method returns the primary key of a table. Note that this raises
- an exception if the table doesn't have a primary key.
-
- 3.3. get_databases - get list of databases in the system
- --------------------------------------------------------
- Syntax: get_databases()
- Parameters: none
- Returns: list of databases in the system
- Description:
- Although you can do this with a simple select, it is added here for
- convenience
-
- 3.4. get_tables - get list of tables in connected database
- ----------------------------------------------------------
- Syntax: get_tables()
- Parameters: none
- Returns: list of tables in connected database
-
- 3.5. get_attnames
- -----------------
- Syntax:
- get_attnames(table)
- Parameters:
- table - name of table
- Returns:
- Dictionary of attribute names (the names are the keys, the values
- are the names of the attributes' types)
- Description:
- Given the name of a table, digs out the set of attribute names.
-
- 3.6. get - get a tuple from a database table
- --------------------------------------------
- Syntax:
- get(table, arg, [keyname])
- Parameters:
- table - name of table
- arg - either a dictionary or the value to be looked up
- keyname - name of field to use as key (optional)
- Returns:
- A dictionary mapping attribute names to row values.
- Description:
- This method is the basic mechanism to get a single row. It assumes
- that the key specifies a unique row. If keyname is not specified
- then the primary key for the table is used. If arg is a dictionary
- then the value for the key is taken from it and it is modified to
- include the new values, replacing existing values where necessary.
- The oid is also put into the dictionary but in order to allow the
- caller to work with multiple tables, the attribute name is munged
- to make it unique. It consists of the string "oid_" followed by
- the name of the table.
-
-
- 3.7. insert - insert a tuple into a database table
- --------------------------------------------------
- Syntax:
- insert(table, a)
- Parameters:
- table - name of table
- a - a dictionary of values
- Returns:
- The OID of the newly inserted row.
- Description:
- This method inserts values into the table specified filling in the
- values from the dictionary. It then reloads the dictionary with the
- values from the database. This causes the dictionary to be updated
- with values that are modified by rules, triggers, etc.
-
- Due to the way that this function works you will find inserts taking
- longer and longer as your table gets bigger. To overcome this problem
- simply add an index onto the OID of any table that you think may get
- large over time.
-
-
- 3.8. update
- -----------
- Syntax:
- update(table, a)
- Parameters:
- table - name of table
- a - a dictionary of values
- Returns:
- A dictionary with the new row
- Description:
- Similar to insert but updates an existing row. The update is based
- on the OID value as munged by get. The array returned is the
- one sent modified to reflect any changes caused by the update due
- to triggers, rules, defaults, etc.
-
- 3.9. clear
- ----------
- Syntax:
- clear(table, [a])
- Parameters:
- table - name of table
- a - a dictionary of values
- Returns:
- A dictionary with an empty row
- Description:
- This method clears all the attributes to values determined by the types.
- Numeric types are set to 0, dates are set to 'TODAY' and everything
- else is set to the empty string. If the array argument is present,
- it is used as the array and any entries matching attribute names
- are cleared with everything else left unchanged.
-
- 3.8. delete
- -----------
- Syntax:
- delete(table, a)
- Parameters:
- table - name of table
- a - a dictionary of values
- Returns:
- None
- Description:
- This method deletes the row from a table. It deletes based on the OID
- as munged as described above.
-
-
-4. DB-API reference
-===================
-
- This section needs to be written.
-
-
-5. Todo
+3. Todo
=======
The large object and direct access functions need much more attention.
The fetch method should use real cursors.
-6. Future directions
+4. Future directions
====================
Users should be able to register their own types with _pg.
OSDN Git Service
