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Use lower-case SGML attribute values

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for DocBook XML compatibility
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Peter Eisentraut
2017-10-08 22:00:57 -04:00
parent 82c117cb90
commit 44b3230e82
120 changed files with 1104 additions and 1104 deletions
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174
doc/src/sgml/ref/create_aggregate.sgml
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@@ -22,59 +22,59 @@ PostgreSQL documentation
<refsynopsisdiv>
<synopsis>
CREATE AGGREGATE <replaceable class="parameter">name</replaceable> ( [ <replaceable class="parameter">argmode</replaceable> ] [ <replaceable class="parameter">argname</replaceable> ] <replaceable class="parameter">arg_data_type</replaceable> [ , ... ] ) (
SFUNC = <replaceable class="PARAMETER">sfunc</replaceable>,
STYPE = <replaceable class="PARAMETER">state_data_type</replaceable>
[ , SSPACE = <replaceable class="PARAMETER">state_data_size</replaceable> ]
[ , FINALFUNC = <replaceable class="PARAMETER">ffunc</replaceable> ]
SFUNC = <replaceable class="parameter">sfunc</replaceable>,
STYPE = <replaceable class="parameter">state_data_type</replaceable>
[ , SSPACE = <replaceable class="parameter">state_data_size</replaceable> ]
[ , FINALFUNC = <replaceable class="parameter">ffunc</replaceable> ]
[ , FINALFUNC_EXTRA ]
[ , COMBINEFUNC = <replaceable class="PARAMETER">combinefunc</replaceable> ]
[ , SERIALFUNC = <replaceable class="PARAMETER">serialfunc</replaceable> ]
[ , DESERIALFUNC = <replaceable class="PARAMETER">deserialfunc</replaceable> ]
[ , INITCOND = <replaceable class="PARAMETER">initial_condition</replaceable> ]
[ , MSFUNC = <replaceable class="PARAMETER">msfunc</replaceable> ]
[ , MINVFUNC = <replaceable class="PARAMETER">minvfunc</replaceable> ]
[ , MSTYPE = <replaceable class="PARAMETER">mstate_data_type</replaceable> ]
[ , MSSPACE = <replaceable class="PARAMETER">mstate_data_size</replaceable> ]
[ , MFINALFUNC = <replaceable class="PARAMETER">mffunc</replaceable> ]
[ , COMBINEFUNC = <replaceable class="parameter">combinefunc</replaceable> ]
[ , SERIALFUNC = <replaceable class="parameter">serialfunc</replaceable> ]
[ , DESERIALFUNC = <replaceable class="parameter">deserialfunc</replaceable> ]
[ , INITCOND = <replaceable class="parameter">initial_condition</replaceable> ]
[ , MSFUNC = <replaceable class="parameter">msfunc</replaceable> ]
[ , MINVFUNC = <replaceable class="parameter">minvfunc</replaceable> ]
[ , MSTYPE = <replaceable class="parameter">mstate_data_type</replaceable> ]
[ , MSSPACE = <replaceable class="parameter">mstate_data_size</replaceable> ]
[ , MFINALFUNC = <replaceable class="parameter">mffunc</replaceable> ]
[ , MFINALFUNC_EXTRA ]
[ , MINITCOND = <replaceable class="PARAMETER">minitial_condition</replaceable> ]
[ , SORTOP = <replaceable class="PARAMETER">sort_operator</replaceable> ]
[ , MINITCOND = <replaceable class="parameter">minitial_condition</replaceable> ]
[ , SORTOP = <replaceable class="parameter">sort_operator</replaceable> ]
[ , PARALLEL = { SAFE | RESTRICTED | UNSAFE } ]
)
CREATE AGGREGATE <replaceable class="parameter">name</replaceable> ( [ [ <replaceable class="parameter">argmode</replaceable> ] [ <replaceable class="parameter">argname</replaceable> ] <replaceable class="parameter">arg_data_type</replaceable> [ , ... ] ]
ORDER BY [ <replaceable class="parameter">argmode</replaceable> ] [ <replaceable class="parameter">argname</replaceable> ] <replaceable class="parameter">arg_data_type</replaceable> [ , ... ] ) (
SFUNC = <replaceable class="PARAMETER">sfunc</replaceable>,
STYPE = <replaceable class="PARAMETER">state_data_type</replaceable>
[ , SSPACE = <replaceable class="PARAMETER">state_data_size</replaceable> ]
[ , FINALFUNC = <replaceable class="PARAMETER">ffunc</replaceable> ]
SFUNC = <replaceable class="parameter">sfunc</replaceable>,
STYPE = <replaceable class="parameter">state_data_type</replaceable>
[ , SSPACE = <replaceable class="parameter">state_data_size</replaceable> ]
[ , FINALFUNC = <replaceable class="parameter">ffunc</replaceable> ]
[ , FINALFUNC_EXTRA ]
[ , INITCOND = <replaceable class="PARAMETER">initial_condition</replaceable> ]
[ , INITCOND = <replaceable class="parameter">initial_condition</replaceable> ]
[ , PARALLEL = { SAFE | RESTRICTED | UNSAFE } ]
[ , HYPOTHETICAL ]
)
<phrase>or the old syntax</phrase>
CREATE AGGREGATE <replaceable class="PARAMETER">name</replaceable> (
BASETYPE = <replaceable class="PARAMETER">base_type</replaceable>,
SFUNC = <replaceable class="PARAMETER">sfunc</replaceable>,
STYPE = <replaceable class="PARAMETER">state_data_type</replaceable>
[ , SSPACE = <replaceable class="PARAMETER">state_data_size</replaceable> ]
[ , FINALFUNC = <replaceable class="PARAMETER">ffunc</replaceable> ]
CREATE AGGREGATE <replaceable class="parameter">name</replaceable> (
BASETYPE = <replaceable class="parameter">base_type</replaceable>,
SFUNC = <replaceable class="parameter">sfunc</replaceable>,
STYPE = <replaceable class="parameter">state_data_type</replaceable>
[ , SSPACE = <replaceable class="parameter">state_data_size</replaceable> ]
[ , FINALFUNC = <replaceable class="parameter">ffunc</replaceable> ]
[ , FINALFUNC_EXTRA ]
[ , COMBINEFUNC = <replaceable class="PARAMETER">combinefunc</replaceable> ]
[ , SERIALFUNC = <replaceable class="PARAMETER">serialfunc</replaceable> ]
[ , DESERIALFUNC = <replaceable class="PARAMETER">deserialfunc</replaceable> ]
[ , INITCOND = <replaceable class="PARAMETER">initial_condition</replaceable> ]
[ , MSFUNC = <replaceable class="PARAMETER">msfunc</replaceable> ]
[ , MINVFUNC = <replaceable class="PARAMETER">minvfunc</replaceable> ]
[ , MSTYPE = <replaceable class="PARAMETER">mstate_data_type</replaceable> ]
[ , MSSPACE = <replaceable class="PARAMETER">mstate_data_size</replaceable> ]
[ , MFINALFUNC = <replaceable class="PARAMETER">mffunc</replaceable> ]
[ , COMBINEFUNC = <replaceable class="parameter">combinefunc</replaceable> ]
[ , SERIALFUNC = <replaceable class="parameter">serialfunc</replaceable> ]
[ , DESERIALFUNC = <replaceable class="parameter">deserialfunc</replaceable> ]
[ , INITCOND = <replaceable class="parameter">initial_condition</replaceable> ]
[ , MSFUNC = <replaceable class="parameter">msfunc</replaceable> ]
[ , MINVFUNC = <replaceable class="parameter">minvfunc</replaceable> ]
[ , MSTYPE = <replaceable class="parameter">mstate_data_type</replaceable> ]
[ , MSSPACE = <replaceable class="parameter">mstate_data_size</replaceable> ]
[ , MFINALFUNC = <replaceable class="parameter">mffunc</replaceable> ]
[ , MFINALFUNC_EXTRA ]
[ , MINITCOND = <replaceable class="PARAMETER">minitial_condition</replaceable> ]
[ , SORTOP = <replaceable class="PARAMETER">sort_operator</replaceable> ]
[ , MINITCOND = <replaceable class="parameter">minitial_condition</replaceable> ]
[ , SORTOP = <replaceable class="parameter">sort_operator</replaceable> ]
)
</synopsis>
</refsynopsisdiv>
@@ -112,19 +112,19 @@ CREATE AGGREGATE <replaceable class="PARAMETER">name</replaceable> (
A simple aggregate function is made from one or two ordinary
functions:
a state transition function
<replaceable class="PARAMETER">sfunc</replaceable>,
<replaceable class="parameter">sfunc</replaceable>,
and an optional final calculation function
<replaceable class="PARAMETER">ffunc</replaceable>.
<replaceable class="parameter">ffunc</replaceable>.
These are used as follows:
<programlisting>
<replaceable class="PARAMETER">sfunc</replaceable>( internal-state, next-data-values ) ---> next-internal-state
<replaceable class="PARAMETER">ffunc</replaceable>( internal-state ) ---> aggregate-value
<replaceable class="parameter">sfunc</replaceable>( internal-state, next-data-values ) ---> next-internal-state
<replaceable class="parameter">ffunc</replaceable>( internal-state ) ---> aggregate-value
</programlisting>
</para>
<para>
<productname>PostgreSQL</productname> creates a temporary variable
of data type <replaceable class="PARAMETER">stype</replaceable>
of data type <replaceable class="parameter">stype</replaceable>
to hold the current internal state of the aggregate. At each input row,
the aggregate argument value(s) are calculated and
the state transition function is invoked with the current state value
@@ -155,9 +155,9 @@ CREATE AGGREGATE <replaceable class="PARAMETER">name</replaceable> (
all-nonnull input values.
This is handy for implementing aggregates like <function>max</function>.
Note that this behavior is only available when
<replaceable class="PARAMETER">state_data_type</replaceable>
<replaceable class="parameter">state_data_type</replaceable>
is the same as the first
<replaceable class="PARAMETER">arg_data_type</replaceable>.
<replaceable class="parameter">arg_data_type</replaceable>.
When these types are different, you must supply a nonnull initial
condition or use a nonstrict transition function.
</para>
@@ -224,7 +224,7 @@ CREATE AGGREGATE <replaceable class="PARAMETER">name</replaceable> (
An aggregate can optionally support <firstterm>partial aggregation</>,
as described in <xref linkend="xaggr-partial-aggregates">.
This requires specifying the <literal>COMBINEFUNC</> parameter.
If the <replaceable class="PARAMETER">state_data_type</replaceable>
If the <replaceable class="parameter">state_data_type</replaceable>
is <type>internal</>, it's usually also appropriate to provide the
<literal>SERIALFUNC</> and <literal>DESERIALFUNC</> parameters so that
parallel aggregation is possible. Note that the aggregate must also be
@@ -268,7 +268,7 @@ SELECT col FROM tab ORDER BY col USING sortop LIMIT 1;
<variablelist>
<varlistentry>
<term><replaceable class="PARAMETER">name</replaceable></term>
<term><replaceable class="parameter">name</replaceable></term>
<listitem>
<para>
The name (optionally schema-qualified) of the aggregate function
@@ -302,7 +302,7 @@ SELECT col FROM tab ORDER BY col USING sortop LIMIT 1;
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">arg_data_type</replaceable></term>
<term><replaceable class="parameter">arg_data_type</replaceable></term>
<listitem>
<para>
An input data type on which this aggregate function operates.
@@ -314,7 +314,7 @@ SELECT col FROM tab ORDER BY col USING sortop LIMIT 1;
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">base_type</replaceable></term>
<term><replaceable class="parameter">base_type</replaceable></term>
<listitem>
<para>
In the old syntax for <command>CREATE AGGREGATE</>, the input data type
@@ -329,18 +329,18 @@ SELECT col FROM tab ORDER BY col USING sortop LIMIT 1;
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">sfunc</replaceable></term>
<term><replaceable class="parameter">sfunc</replaceable></term>
<listitem>
<para>
The name of the state transition function to be called for each
input row. For a normal <replaceable class="PARAMETER">N</>-argument
aggregate function, the <replaceable class="PARAMETER">sfunc</>
must take <replaceable class="PARAMETER">N</>+1 arguments,
input row. For a normal <replaceable class="parameter">N</>-argument
aggregate function, the <replaceable class="parameter">sfunc</>
must take <replaceable class="parameter">N</>+1 arguments,
the first being of type <replaceable
class="PARAMETER">state_data_type</replaceable> and the rest
class="parameter">state_data_type</replaceable> and the rest
matching the declared input data type(s) of the aggregate.
The function must return a value of type <replaceable
class="PARAMETER">state_data_type</replaceable>. This function
class="parameter">state_data_type</replaceable>. This function
takes the current state value and the current input data value(s),
and returns the next state value.
</para>
@@ -355,7 +355,7 @@ SELECT col FROM tab ORDER BY col USING sortop LIMIT 1;
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">state_data_type</replaceable></term>
<term><replaceable class="parameter">state_data_type</replaceable></term>
<listitem>
<para>
The data type for the aggregate's state value.
@@ -364,7 +364,7 @@ SELECT col FROM tab ORDER BY col USING sortop LIMIT 1;
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">state_data_size</replaceable></term>
<term><replaceable class="parameter">state_data_size</replaceable></term>
<listitem>
<para>
The approximate average size (in bytes) of the aggregate's state value.
@@ -380,19 +380,19 @@ SELECT col FROM tab ORDER BY col USING sortop LIMIT 1;
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">ffunc</replaceable></term>
<term><replaceable class="parameter">ffunc</replaceable></term>
<listitem>
<para>
The name of the final function called to compute the aggregate's
result after all input rows have been traversed.
For a normal aggregate, this function
must take a single argument of type <replaceable
class="PARAMETER">state_data_type</replaceable>. The return
class="parameter">state_data_type</replaceable>. The return
data type of the aggregate is defined as the return type of this
function. If <replaceable class="PARAMETER">ffunc</replaceable>
function. If <replaceable class="parameter">ffunc</replaceable>
is not specified, then the ending state value is used as the
aggregate's result, and the return type is <replaceable
class="PARAMETER">state_data_type</replaceable>.
class="parameter">state_data_type</replaceable>.
</para>
<para>
@@ -413,30 +413,30 @@ SELECT col FROM tab ORDER BY col USING sortop LIMIT 1;
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">combinefunc</replaceable></term>
<term><replaceable class="parameter">combinefunc</replaceable></term>
<listitem>
<para>
The <replaceable class="PARAMETER">combinefunc</replaceable> function
The <replaceable class="parameter">combinefunc</replaceable> function
may optionally be specified to allow the aggregate function to support
partial aggregation. If provided,
the <replaceable class="PARAMETER">combinefunc</replaceable> must
combine two <replaceable class="PARAMETER">state_data_type</replaceable>
the <replaceable class="parameter">combinefunc</replaceable> must
combine two <replaceable class="parameter">state_data_type</replaceable>
values, each containing the result of aggregation over some subset of
the input values, to produce a
new <replaceable class="PARAMETER">state_data_type</replaceable> that
new <replaceable class="parameter">state_data_type</replaceable> that
represents the result of aggregating over both sets of inputs. This
function can be thought of as
an <replaceable class="PARAMETER">sfunc</replaceable>, where instead of
an <replaceable class="parameter">sfunc</replaceable>, where instead of
acting upon an individual input row and adding it to the running
aggregate state, it adds another aggregate state to the running state.
</para>
<para>
The <replaceable class="PARAMETER">combinefunc</replaceable> must be
The <replaceable class="parameter">combinefunc</replaceable> must be
declared as taking two arguments of
the <replaceable class="PARAMETER">state_data_type</replaceable> and
the <replaceable class="parameter">state_data_type</replaceable> and
returning a value of
the <replaceable class="PARAMETER">state_data_type</replaceable>.
the <replaceable class="parameter">state_data_type</replaceable>.
Optionally this function may be <quote>strict</quote>. In this case the
function will not be called when either of the input states are null;
the other state will be taken as the correct result.
@@ -444,11 +444,11 @@ SELECT col FROM tab ORDER BY col USING sortop LIMIT 1;
<para>
For aggregate functions
whose <replaceable class="PARAMETER">state_data_type</replaceable>
whose <replaceable class="parameter">state_data_type</replaceable>
is <type>internal</type>,
the <replaceable class="PARAMETER">combinefunc</replaceable> must not
the <replaceable class="parameter">combinefunc</replaceable> must not
be strict. In this case
the <replaceable class="PARAMETER">combinefunc</replaceable> must
the <replaceable class="parameter">combinefunc</replaceable> must
ensure that null states are handled correctly and that the state being
returned is properly stored in the aggregate memory context.
</para>
@@ -456,28 +456,28 @@ SELECT col FROM tab ORDER BY col USING sortop LIMIT 1;
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">serialfunc</replaceable></term>
<term><replaceable class="parameter">serialfunc</replaceable></term>
<listitem>
<para>
An aggregate function
whose <replaceable class="PARAMETER">state_data_type</replaceable>
whose <replaceable class="parameter">state_data_type</replaceable>
is <type>internal</> can participate in parallel aggregation only if it
has a <replaceable class="PARAMETER">serialfunc</replaceable> function,
has a <replaceable class="parameter">serialfunc</replaceable> function,
which must serialize the aggregate state into a <type>bytea</> value for
transmission to another process. This function must take a single
argument of type <type>internal</> and return type <type>bytea</>. A
corresponding <replaceable class="PARAMETER">deserialfunc</replaceable>
corresponding <replaceable class="parameter">deserialfunc</replaceable>
is also required.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">deserialfunc</replaceable></term>
<term><replaceable class="parameter">deserialfunc</replaceable></term>
<listitem>
<para>
Deserialize a previously serialized aggregate state back into
<replaceable class="PARAMETER">state_data_type</replaceable>. This
<replaceable class="parameter">state_data_type</replaceable>. This
function must take two arguments of types <type>bytea</>
and <type>internal</>, and produce a result of type <type>internal</>.
(Note: the second, <type>internal</> argument is unused, but is required
@@ -487,19 +487,19 @@ SELECT col FROM tab ORDER BY col USING sortop LIMIT 1;
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">initial_condition</replaceable></term>
<term><replaceable class="parameter">initial_condition</replaceable></term>
<listitem>
<para>
The initial setting for the state value. This must be a string
constant in the form accepted for the data type <replaceable
class="PARAMETER">state_data_type</replaceable>. If not
class="parameter">state_data_type</replaceable>. If not
specified, the state value starts out null.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">msfunc</replaceable></term>
<term><replaceable class="parameter">msfunc</replaceable></term>
<listitem>
<para>
The name of the forward state transition function to be called for each
@@ -512,7 +512,7 @@ SELECT col FROM tab ORDER BY col USING sortop LIMIT 1;
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">minvfunc</replaceable></term>
<term><replaceable class="parameter">minvfunc</replaceable></term>
<listitem>
<para>
The name of the inverse state transition function to be used in
@@ -526,7 +526,7 @@ SELECT col FROM tab ORDER BY col USING sortop LIMIT 1;
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">mstate_data_type</replaceable></term>
<term><replaceable class="parameter">mstate_data_type</replaceable></term>
<listitem>
<para>
The data type for the aggregate's state value, when using
@@ -536,7 +536,7 @@ SELECT col FROM tab ORDER BY col USING sortop LIMIT 1;
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">mstate_data_size</replaceable></term>
<term><replaceable class="parameter">mstate_data_size</replaceable></term>
<listitem>
<para>
The approximate average size (in bytes) of the aggregate's state
@@ -547,7 +547,7 @@ SELECT col FROM tab ORDER BY col USING sortop LIMIT 1;
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">mffunc</replaceable></term>
<term><replaceable class="parameter">mffunc</replaceable></term>
<listitem>
<para>
The name of the final function called to compute the aggregate's
@@ -564,7 +564,7 @@ SELECT col FROM tab ORDER BY col USING sortop LIMIT 1;
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">minitial_condition</replaceable></term>
<term><replaceable class="parameter">minitial_condition</replaceable></term>
<listitem>
<para>
The initial setting for the state value, when using moving-aggregate
@@ -574,7 +574,7 @@ SELECT col FROM tab ORDER BY col USING sortop LIMIT 1;
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">sort_operator</replaceable></term>
<term><replaceable class="parameter">sort_operator</replaceable></term>
<listitem>
<para>
The associated sort operator for a <function>MIN</>- or