Add psql \set ON_ERROR_ROLLBACK to allow statements in a transaction to

error without affecting the entire transaction.  Valid values are
"on|interactive|off".

diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index 3a80b7f..41de5d5 100644 (file)
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -1,5 +1,5 @@
 <!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/psql-ref.sgml,v 1.134 2005/03/14 06:19:01 tgl Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/psql-ref.sgml,v 1.135 2005/04/28 13:09:59 momjian Exp $
 PostgreSQL documentation
 -->
 
@@ -2050,6 +2050,28 @@ bar
       </varlistentry>
 
       <varlistentry>
+      <indexterm>
+       <primary>rollback</primary>
+       <secondary>psql</secondary>
+      </indexterm>
+        <term><varname>ON_ERROR_ROLLBACK</varname></term>
+        <listitem>
+        <para>
+        When <literal>on</>, if a statement in a transaction block
+        generates an error, the error is ignored and the transaction
+        continues. When <literal>interactive</>, such errors are only
+        ignored in interactive sessions, and not when reading script
+        files. When <literal>off</> (the default), a statement in a
+        transaction block that generates an error aborts the entire
+        transaction. The on_error_rollback-on mode works by issuing an
+        implicit <command>SAVEPONT</> for you, just before each command
+        that is in a transaction block, and rolls back to the savepoint
+        on error.
+        </para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
         <term><varname>ON_ERROR_STOP</varname></term>
         <listitem>
         <para>

diff --git a/src/bin/psql/common.c b/src/bin/psql/common.c
index 6d03a4a..0feec43 100644 (file)
--- a/src/bin/psql/common.c
+++ b/src/bin/psql/common.c
@@ -3,7 +3,7 @@
  *
  * Copyright (c) 2000-2005, PostgreSQL Global Development Group
  *
- * $PostgreSQL: pgsql/src/bin/psql/common.c,v 1.96 2005/02/22 04:40:52 momjian Exp $
+ * $PostgreSQL: pgsql/src/bin/psql/common.c,v 1.97 2005/04/28 13:09:59 momjian Exp $
  */
 #include "postgres_fe.h"
 #include "common.h"
@@ -941,11 +941,13 @@ PrintQueryResults(PGresult *results)
 bool
 SendQuery(const char *query)
 {
-       PGresult   *results;
-       TimevalStruct before,
-                               after;
-       bool            OK;
-
+       PGresult        *results;
+       TimevalStruct before, after;
+       bool OK, on_error_rollback_savepoint = false;
+       PGTransactionStatusType transaction_status;
+       static bool             on_error_rollback_warning = false;
+       const char *rollback_str;
+       
        if (!pset.db)
        {
                psql_error("You are currently not connected to a database.\n");
@@ -973,7 +975,9 @@ SendQuery(const char *query)
 
        SetCancelConn();
 
-       if (PQtransactionStatus(pset.db) == PQTRANS_IDLE &&
+       transaction_status = PQtransactionStatus(pset.db);
+
+       if (transaction_status == PQTRANS_IDLE &&
                !GetVariableBool(pset.vars, "AUTOCOMMIT") &&
                !command_no_begin(query))
        {
@@ -987,6 +991,33 @@ SendQuery(const char *query)
                }
                PQclear(results);
        }
+       else if (transaction_status == PQTRANS_INTRANS &&
+                        (rollback_str = GetVariable(pset.vars, "ON_ERROR_ROLLBACK")) != NULL &&
+                        /* !off and !interactive is 'on' */
+                        pg_strcasecmp(rollback_str, "off") != 0 &&
+                        (pset.cur_cmd_interactive ||
+                         pg_strcasecmp(rollback_str, "interactive") != 0))
+       {
+               if (on_error_rollback_warning == false && pset.sversion < 80000)
+               {
+                       fprintf(stderr, _("The server version (%d) does not support savepoints for ON_ERROR_ROLLBACK.\n"),
+                               pset.sversion);
+                       on_error_rollback_warning = true;
+               }
+               else
+               {
+                       results = PQexec(pset.db, "SAVEPOINT pg_psql_temporary_savepoint");
+                       if (PQresultStatus(results) != PGRES_COMMAND_OK)
+                       {
+                               psql_error("%s", PQerrorMessage(pset.db));
+                               PQclear(results);
+                               ResetCancelConn();
+                               return false;
+                       }
+                       PQclear(results);
+                       on_error_rollback_savepoint = true;
+               }
+       }
 
        if (pset.timing)
                GETTIMEOFDAY(&before);
@@ -1005,6 +1036,41 @@ SendQuery(const char *query)
 
        PQclear(results);
 
+       /* If we made a temporary savepoint, possibly release/rollback */
+       if (on_error_rollback_savepoint)
+       {
+               transaction_status = PQtransactionStatus(pset.db);
+
+               /* We always rollback on an error */
+               if (transaction_status == PQTRANS_INERROR)
+                       results = PQexec(pset.db, "ROLLBACK TO pg_psql_temporary_savepoint");
+               /* If they are no longer in a transaction, then do nothing */
+               else if (transaction_status != PQTRANS_INTRANS)
+                       results = NULL;
+               else
+               {
+                       /* 
+                        *      Do nothing if they are messing with savepoints themselves:
+                        *      If the user did RELEASE or ROLLBACK, our savepoint is gone.
+                        *      If they issued a SAVEPOINT, releasing ours would remove theirs.
+                        */
+                       if (strcmp(PQcmdStatus(results), "SAVEPOINT") == 0 ||
+                               strcmp(PQcmdStatus(results), "RELEASE") == 0 ||
+                               strcmp(PQcmdStatus(results), "ROLLBACK") ==0)
+                               results = NULL;
+                       else
+                               results = PQexec(pset.db, "RELEASE pg_psql_temporary_savepoint");
+               }
+               if (PQresultStatus(results) != PGRES_COMMAND_OK)
+               {
+                       psql_error("%s", PQerrorMessage(pset.db));
+                       PQclear(results);
+                       ResetCancelConn();
+                       return false;
+               }
+               PQclear(results);
+       }
+
        /* Possible microtiming output */
        if (OK && pset.timing)
                printf(_("Time: %.3f ms\n"), DIFF_MSEC(&after, &before));