<!--
doc/src/sgml/ref/create_type.sgml
PostgreSQL documentation
-->
<refentry id="sql-createtype">
<indexterm zone="sql-createtype">
<primary>CREATE TYPE</primary>
</indexterm>
<refmeta>
<refentrytitle>CREATE TYPE</refentrytitle>
<manvolnum>7</manvolnum>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
</refmeta>
<refnamediv>
<refname>CREATE TYPE</refname>
<refpurpose>define a new data type</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
CREATE TYPE <replaceable class="parameter">name</replaceable> AS
( [ <replaceable class="parameter">attribute_name</replaceable> <replaceable class="parameter">data_type</replaceable> [ COLLATE <replaceable>collation</replaceable> ] [, ... ] ] )
CREATE TYPE <replaceable class="parameter">name</replaceable> AS ENUM
( [ '<replaceable class="parameter">label</replaceable>' [, ... ] ] )
CREATE TYPE <replaceable class="parameter">name</replaceable> AS RANGE (
SUBTYPE = <replaceable class="parameter">subtype</replaceable>
[ , SUBTYPE_OPCLASS = <replaceable class="parameter">subtype_operator_class</replaceable> ]
[ , COLLATION = <replaceable class="parameter">collation</replaceable> ]
[ , CANONICAL = <replaceable class="parameter">canonical_function</replaceable> ]
[ , SUBTYPE_DIFF = <replaceable class="parameter">subtype_diff_function</replaceable> ]
[ , MULTIRANGE_TYPE_NAME = <replaceable class="parameter">multirange_type_name</replaceable> ]
)
CREATE TYPE <replaceable class="parameter">name</replaceable> (
INPUT = <replaceable class="parameter">input_function</replaceable>,
OUTPUT = <replaceable class="parameter">output_function</replaceable>
[ , RECEIVE = <replaceable class="parameter">receive_function</replaceable> ]
[ , SEND = <replaceable class="parameter">send_function</replaceable> ]
[ , TYPMOD_IN = <replaceable class="parameter">type_modifier_input_function</replaceable> ]
[ , TYPMOD_OUT = <replaceable class="parameter">type_modifier_output_function</replaceable> ]
[ , ANALYZE = <replaceable class="parameter">analyze_function</replaceable> ]
[ , SUBSCRIPT = <replaceable class="parameter">subscript_function</replaceable> ]
[ , INTERNALLENGTH = { <replaceable class="parameter">internallength</replaceable> | VARIABLE } ]
[ , PASSEDBYVALUE ]
[ , ALIGNMENT = <replaceable class="parameter">alignment</replaceable> ]
[ , STORAGE = <replaceable class="parameter">storage</replaceable> ]
[ , LIKE = <replaceable class="parameter">like_type</replaceable> ]
[ , CATEGORY = <replaceable class="parameter">category</replaceable> ]
[ , PREFERRED = <replaceable class="parameter">preferred</replaceable> ]
[ , DEFAULT = <replaceable class="parameter">default</replaceable> ]
[ , ELEMENT = <replaceable class="parameter">element</replaceable> ]
[ , DELIMITER = <replaceable class="parameter">delimiter</replaceable> ]
[ , COLLATABLE = <replaceable class="parameter">collatable</replaceable> ]
)
CREATE TYPE <replaceable class="parameter">name</replaceable>
</synopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para>
<command>CREATE TYPE</command> registers a new data type for use in
the current database. The user who defines a type becomes its
owner.
</para>
<para>
If a schema name is given then the type is created in the specified
schema. Otherwise it is created in the current schema. The type
name must be distinct from the name of any existing type or domain
in the same schema. (Because tables have associated data types,
the type name must also be distinct from the name of any existing
table in the same schema.)
</para>
<para>
There are five forms of <command>CREATE TYPE</command>, as shown in the
syntax synopsis above. They respectively create a <firstterm>composite
type</firstterm>, an <firstterm>enum type</firstterm>, a <firstterm>range type</firstterm>, a
<firstterm>base type</firstterm>, or a <firstterm>shell