Add smallserial pseudotype.

This is just like serial and bigserial, except it generates an int2
column rather than int4 or int8.

Mike Pultz, reviewed by Brar Piening and Josh Kupershmidt

4 files changed, 40 insertions, 5 deletions

diff --git a/doc/src/sgml/datatype.sgml b/doc/src/sgml/datatype.sgml
index ab8eb2d30bb..0b4f978d985 100644
--- a/doc/src/sgml/datatype.sgml
+++ b/doc/src/sgml/datatype.sgml
@@ -199,6 +199,12 @@
       </row>
 
       <row>
+       <entry><type>smallserial</type></entry>
+       <entry><type>serial2</type></entry>
+       <entry>autoincrementing two-byte integer</entry>
+      </row>
+
+      <row>
        <entry><type>serial</type></entry>
        <entry><type>serial4</type></entry>
        <entry>autoincrementing four-byte integer</entry>
@@ -369,6 +375,13 @@
        </row>
 
        <row>
+        <entry><type>smallserial</type></entry>
+        <entry>2 bytes</entry>
+        <entry>small autoincrementing integer</entry>
+        <entry>1 to 32767</entry>
+       </row>
+
+       <row>
         <entry><type>serial</></entry>
         <entry>4 bytes</entry>
         <entry>autoincrementing integer</entry>
@@ -743,6 +756,10 @@ NUMERIC
     <title>Serial Types</title>
 
     <indexterm zone="datatype-serial">
+     <primary>smallserial</primary>
+    </indexterm>
+
+    <indexterm zone="datatype-serial">
      <primary>serial</primary>
     </indexterm>
 
@@ -751,6 +768,10 @@ NUMERIC
     </indexterm>
 
     <indexterm zone="datatype-serial">
+     <primary>serial2</primary>
+    </indexterm>
+
+    <indexterm zone="datatype-serial">
      <primary>serial4</primary>
     </indexterm>
 
@@ -769,8 +790,8 @@ NUMERIC
     </indexterm>
 
     <para>
-     The data types <type>serial</type> and <type>bigserial</type>
-     are not true types, but merely
+     The data types <type>smallserial</type>, <type>serial</type> and 
+     <type>bigserial</type> are not true types, but merely
      a notational convenience for creating unique identifier columns
      (similar to the <literal>AUTO_INCREMENT</literal> property
      supported by some other databases). In the current
@@ -828,7 +849,9 @@ ALTER SEQUENCE <replaceable class="parameter">tablename</replaceable>_<replaceab
      the same way, except that they create a <type>bigint</type>
      column.  <type>bigserial</type> should be used if you anticipate
      the use of more than 2<superscript>31</> identifiers over the
-     lifetime of the table.
+     lifetime of the table. The type names <type>smallserial</type> and
+     <type>serial2</type> also work the same way, execpt that they
+     create a <type>smallint</type> column.
     </para>
 
     <para>
diff --git a/doc/src/sgml/ecpg.sgml b/doc/src/sgml/ecpg.sgml
index def250c156c..847012293be 100644
--- a/doc/src/sgml/ecpg.sgml
+++ b/doc/src/sgml/ecpg.sgml
@@ -845,6 +845,11 @@ do
       </row>
 
       <row>
+       <entry><type>smallserial</type></entry>
+       <entry><type>short</type></entry>
+      </row>
+
+      <row>
        <entry><type>serial</type></entry>
        <entry><type>int</type></entry>
       </row>
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 8f223d68913..628fbef0017 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -13366,7 +13366,7 @@ SELECT pg_type_is_visible('myschema.widget'::regtype);
       <row>
        <entry><literal><function>pg_get_serial_sequence(<parameter>table_name</parameter>, <parameter>column_name</parameter>)</function></literal></entry>
        <entry><type>text</type></entry>
-       <entry>get name of the sequence that a <type>serial</type> or <type>bigserial</type> column
+       <entry>get name of the sequence that a <type>serial</type>, <type>smallserial</type> or <type>bigserial</type> column
        uses</entry>
       </row>
       <row>
diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c
index 622efe592d4..8744654f34a 100644
--- a/src/backend/parser/parse_utilcmd.c
+++ b/src/backend/parser/parse_utilcmd.c
@@ -307,7 +307,14 @@ transformColumnDefinition(CreateStmtContext *cxt, ColumnDef *column)
 	{
 		char	   *typname = strVal(linitial(column->typeName->names));
 
-		if (strcmp(typname, "serial") == 0 ||
+		if (strcmp(typname, "smallserial") == 0 ||
+			strcmp(typname, "serial2") == 0)
+		{
+			is_serial = true;
+			column->typeName->names = NIL;
+			column->typeName->typeOid = INT2OID;
+		}
+		else if (strcmp(typname, "serial") == 0 ||
 			strcmp(typname, "serial4") == 0)
 		{
 			is_serial = true;