1 files changed, 50 insertions, 0 deletions
diff --git a/doc/src/sgml/ref/create_aggregate.sgml b/doc/src/sgml/ref/create_aggregate.sgml
index 837b83c00b..7a6f8a97fd 100644
--- a/doc/src/sgml/ref/create_aggregate.sgml
+++ b/doc/src/sgml/ref/create_aggregate.sgml
@@ -28,6 +28,9 @@ CREATE AGGREGATE <replaceable class="parameter">name</replaceable> ( [ <replacea
     [ , 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> ]
+    [ , SERIALTYPE = <replaceable class="PARAMETER">serialtype</replaceable> ]
     [ , INITCOND = <replaceable class="PARAMETER">initial_condition</replaceable> ]
     [ , MSFUNC = <replaceable class="PARAMETER">msfunc</replaceable> ]
     [ , MINVFUNC = <replaceable class="PARAMETER">minvfunc</replaceable> ]
@@ -47,6 +50,9 @@ CREATE AGGREGATE <replaceable class="parameter">name</replaceable> ( [ [ <replac
     [ , 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> ]
+    [ , SERIALTYPE = <replaceable class="PARAMETER">serialtype</replaceable> ]
     [ , INITCOND = <replaceable class="PARAMETER">initial_condition</replaceable> ]
     [ , HYPOTHETICAL ]
 )
@@ -61,6 +67,9 @@ CREATE AGGREGATE <replaceable class="PARAMETER">name</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> ]
+    [ , SERIALTYPE = <replaceable class="PARAMETER">serialtype</replaceable> ]
     [ , INITCOND = <replaceable class="PARAMETER">initial_condition</replaceable> ]
     [ , MSFUNC = <replaceable class="PARAMETER">msfunc</replaceable> ]
     [ , MINVFUNC = <replaceable class="PARAMETER">minvfunc</replaceable> ]
@@ -437,6 +446,47 @@ SELECT col FROM tab ORDER BY col USING sortop LIMIT 1;
    </varlistentry>
 
    <varlistentry>
+    <term><replaceable class="PARAMETER">serialfunc</replaceable></term>
+    <listitem>
+     <para>
+      In order to allow aggregate functions with an <literal>INTERNAL</>
+      <replaceable class="PARAMETER">state_data_type</replaceable> to
+      participate in parallel aggregation, the aggregate must have a valid
+      <replaceable class="PARAMETER">serialfunc</replaceable>, which must
+      serialize the aggregate state into <replaceable class="PARAMETER">
+      serialtype</replaceable>. This function must take a single argument of
+      <replaceable class="PARAMETER">state_data_type</replaceable> and return
+      <replaceable class="PARAMETER">serialtype</replaceable>. A
+      corresponding <replaceable class="PARAMETER">deserialfunc</replaceable>
+      is also required.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><replaceable class="PARAMETER">deserialfunc</replaceable></term>
+    <listitem>
+     <para>
+      Deserializes a previously serialized aggregate state back into
+      <replaceable class="PARAMETER">state_data_type</replaceable>. This
+      function must take a single argument of <replaceable class="PARAMETER">
+      serialtype</replaceable> and return <replaceable class="PARAMETER">
+      state_data_type</replaceable>.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><replaceable class="PARAMETER">serialtype</replaceable></term>
+    <listitem>
+     <para>
+      The data type to into which an <literal>INTERNAL</literal> aggregate
+      state should be serialized.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
     <term><replaceable class="PARAMETER">initial_condition</replaceable></term>
     <listitem>
      <para>