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Postgres documentation
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result after all input data has been traversed. The function
must take a single argument of type
<replaceable class="PARAMETER">state_type</replaceable>.
- The output datatype of the aggregate is defined as the return
+ The output data type of the aggregate is defined as the return
type of this function.
If <replaceable class="PARAMETER">ffunc</replaceable>
is not specified, then the ending state value is used as the
<listitem>
<para>
The initial setting for the state value. This must be a literal
- constant in the form accepted for the datatype
+ constant in the form accepted for the data type
<replaceable class="PARAMETER">state_type</replaceable>.
If not specified, the state value starts out NULL.
</para>
that is, an initial value for the internal state value.
This is specified and stored in the database as a field of type
<type>text</type>, but it must be a valid external representation
- of a constant of the state value datatype. If it is not supplied
+ of a constant of the state value data type. If it is not supplied
then the state value starts out NULL.
</para>
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Postgres documentation
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four-byte integers would use the <literal>int4_ops</literal> class;
this operator class includes comparison functions for four-byte
integers. In practice the default operator class for the field's
- datatype is usually sufficient. The main point of having operator classes
- is that for some datatypes, there could be more than one meaningful
- ordering. For example, we might want to sort a complex-number datatype
+ data type is usually sufficient. The main point of having operator classes
+ is that for some data types, there could be more than one meaningful
+ ordering. For example, we might want to sort a complex-number data type
either by absolute value or by real part. We could do this by defining
- two operator classes for the datatype and then selecting the proper
+ two operator classes for the data type and then selecting the proper
class when making an index. There are also some operator classes with
special purposes:
<para>
The operator classes <literal>box_ops</literal> and
<literal>bigbox_ops</literal> both support rtree indices on the
- <literal>box</literal> datatype.
+ <literal>box</literal> data type.
The difference between them is that <literal>bigbox_ops</literal>
scales box coordinates down, to avoid floating point exceptions from
doing multiplication, addition, and subtraction on very large
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the lines of [SHAP86]; however, it must know whether this
strategy is applicable. The current hash-join algorithm
is only correct for operators that represent equality tests;
- furthermore, equality of the datatype must mean bitwise equality
- of the representation of the type. (For example, a datatype that
+ furthermore, equality of the data type must mean bitwise equality
+ of the representation of the type. (For example, a data type that
contains unused bits that don't matter for equality tests could
not be hashjoined.)
The HASHES flag indicates to the query optimizer that a hash join
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<term><replaceable class="parameter">default</replaceable></term>
<listitem>
<para>
- The default value for the datatype. Usually this is omitted,
+ The default value for the data type. Usually this is omitted,
so that the default is NULL.
</para>
</listitem>
<term><replaceable class="parameter">alignment</replaceable></term>
<listitem>
<para>
- Storage alignment requirement of the datatype. If specified, must
+ Storage alignment requirement of the data type. If specified, must
be '<literal>int4</literal>' or '<literal>double</literal>';
the default is '<literal>int4</literal>'.
</para>
<term><replaceable class="parameter">storage</replaceable></term>
<listitem>
<para>
- Storage technique for the datatype. If specified, must
+ Storage technique for the data type. If specified, must
be '<literal>plain</literal>', '<literal>external</literal>',
'<literal>extended</literal>', or '<literal>main</literal>';
the default is '<literal>plain</literal>'.
<para>
The <replaceable class="parameter">storage</replaceable> keyword
- allows selection of TOAST storage method for variable-length datatypes
+ allows selection of TOAST storage method for variable-length data types
(only <literal>plain</literal> is allowed for fixed-length types).
- <literal>plain</literal> disables TOAST for the datatype: it will always
+ <literal>plain</literal> disables TOAST for the data type: it will always
be stored in-line and not compressed.
<literal>extended</literal> is full TOAST capability: the system will
first try to compress a long data value, and will move the value out of
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