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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >ALTER DOMAIN</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK REV="MADE" HREF="mailto:pgsql-docs@postgresql.org"><LINK REL="HOME" TITLE="PostgreSQL 9.2.24 Documentation" HREF="index.html"><LINK REL="UP" TITLE="SQL Commands" HREF="sql-commands.html"><LINK REL="PREVIOUS" TITLE="ALTER DEFAULT PRIVILEGES" HREF="sql-alterdefaultprivileges.html"><LINK REL="NEXT" TITLE="ALTER EXTENSION" HREF="sql-alterextension.html"><LINK REL="STYLESHEET" TYPE="text/css" HREF="stylesheet.css"><META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=ISO-8859-1"><META NAME="creation" CONTENT="2017-11-06T22:43:11"></HEAD ><BODY CLASS="REFENTRY" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="5" ALIGN="center" VALIGN="bottom" ><A HREF="index.html" >PostgreSQL 9.2.24 Documentation</A ></TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A TITLE="ALTER DEFAULT PRIVILEGES" HREF="sql-alterdefaultprivileges.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A HREF="sql-commands.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="60%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="20%" ALIGN="right" VALIGN="top" ><A TITLE="ALTER EXTENSION" HREF="sql-alterextension.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="SQL-ALTERDOMAIN" ></A >ALTER DOMAIN</H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN62852" ></A ><H2 >Name</H2 >ALTER DOMAIN -- change the definition of a domain </DIV ><DIV CLASS="REFSYNOPSISDIV" ><A NAME="AEN62857" ></A ><H2 >Synopsis</H2 ><PRE CLASS="SYNOPSIS" >ALTER DOMAIN <TT CLASS="REPLACEABLE" ><I >name</I ></TT > { SET DEFAULT <TT CLASS="REPLACEABLE" ><I >expression</I ></TT > | DROP DEFAULT } ALTER DOMAIN <TT CLASS="REPLACEABLE" ><I >name</I ></TT > { SET | DROP } NOT NULL ALTER DOMAIN <TT CLASS="REPLACEABLE" ><I >name</I ></TT > ADD <TT CLASS="REPLACEABLE" ><I >domain_constraint</I ></TT > [ NOT VALID ] ALTER DOMAIN <TT CLASS="REPLACEABLE" ><I >name</I ></TT > DROP CONSTRAINT [ IF EXISTS ] <TT CLASS="REPLACEABLE" ><I >constraint_name</I ></TT > [ RESTRICT | CASCADE ] ALTER DOMAIN <TT CLASS="REPLACEABLE" ><I >name</I ></TT > RENAME CONSTRAINT <TT CLASS="REPLACEABLE" ><I >constraint_name</I ></TT > TO <TT CLASS="REPLACEABLE" ><I >new_constraint_name</I ></TT > ALTER DOMAIN <TT CLASS="REPLACEABLE" ><I >name</I ></TT > VALIDATE CONSTRAINT <TT CLASS="REPLACEABLE" ><I >constraint_name</I ></TT > ALTER DOMAIN <TT CLASS="REPLACEABLE" ><I >name</I ></TT > OWNER TO <TT CLASS="REPLACEABLE" ><I >new_owner</I ></TT > ALTER DOMAIN <TT CLASS="REPLACEABLE" ><I >name</I ></TT > RENAME TO <TT CLASS="REPLACEABLE" ><I >new_name</I ></TT > ALTER DOMAIN <TT CLASS="REPLACEABLE" ><I >name</I ></TT > SET SCHEMA <TT CLASS="REPLACEABLE" ><I >new_schema</I ></TT ></PRE ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN62877" ></A ><H2 >Description</H2 ><P > <TT CLASS="COMMAND" >ALTER DOMAIN</TT > changes the definition of an existing domain. There are several sub-forms: </P ><P ></P ><DIV CLASS="VARIABLELIST" ><DL ><DT >SET/DROP DEFAULT</DT ><DD ><P > These forms set or remove the default value for a domain. Note that defaults only apply to subsequent <TT CLASS="COMMAND" >INSERT</TT > commands; they do not affect rows already in a table using the domain. </P ></DD ><DT >SET/DROP NOT NULL</DT ><DD ><P > These forms change whether a domain is marked to allow NULL values or to reject NULL values. You can only <TT CLASS="LITERAL" >SET NOT NULL</TT > when the columns using the domain contain no null values. </P ></DD ><DT >ADD <TT CLASS="REPLACEABLE" ><I >domain_constraint</I ></TT > [ NOT VALID ]</DT ><DD ><P > This form adds a new constraint to a domain using the same syntax as <A HREF="sql-createdomain.html" >CREATE DOMAIN</A >. When a new constraint is added to a domain, all columns using that domain will be checked against the newly added constraint. These checks can be suppressed by adding the new constraint using the <TT CLASS="LITERAL" >NOT VALID</TT > option; the constraint can later be made valid using <TT CLASS="COMMAND" >ALTER DOMAIN ... VALIDATE CONSTRAINT</TT >. Newly inserted or updated rows are always checked against all constraints, even those marked <TT CLASS="LITERAL" >NOT VALID</TT >. <TT CLASS="LITERAL" >NOT VALID</TT > is only accepted for <TT CLASS="LITERAL" >CHECK</TT > constraints. </P ></DD ><DT >DROP CONSTRAINT [ IF EXISTS ]</DT ><DD ><P > This form drops constraints on a domain. If <TT CLASS="LITERAL" >IF EXISTS</TT > is specified and the constraint does not exist, no error is thrown. In this case a notice is issued instead. </P ></DD ><DT >RENAME CONSTRAINT</DT ><DD ><P > This form changes the name of a constraint on a domain. </P ></DD ><DT >VALIDATE CONSTRAINT</DT ><DD ><P > This form validates a constraint previously added as <TT CLASS="LITERAL" >NOT VALID</TT >, that is, verify that all data in columns using the domain satisfy the specified constraint. </P ></DD ><DT >OWNER</DT ><DD ><P > This form changes the owner of the domain to the specified user. </P ></DD ><DT ><TT CLASS="LITERAL" >RENAME</TT ></DT ><DD ><P > This form changes the name of the domain. </P ></DD ><DT >SET SCHEMA</DT ><DD ><P > This form changes the schema of the domain. Any constraints associated with the domain are moved into the new schema as well. </P ></DD ></DL ></DIV ><P > You must own the domain to use <TT CLASS="COMMAND" >ALTER DOMAIN</TT >. To change the schema of a domain, you must also have <TT CLASS="LITERAL" >CREATE</TT > privilege on the new schema. To alter the owner, you must also be a direct or indirect member of the new owning role, and that role must have <TT CLASS="LITERAL" >CREATE</TT > privilege on the domain's schema. (These restrictions enforce that altering the owner doesn't do anything you couldn't do by dropping and recreating the domain. However, a superuser can alter ownership of any domain anyway.) </P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN62934" ></A ><H2 >Parameters</H2 ><P > <P ></P ></P><DIV CLASS="VARIABLELIST" ><DL ><DT ><TT CLASS="REPLACEABLE" ><I >name</I ></TT ></DT ><DD ><P > The name (possibly schema-qualified) of an existing domain to alter. </P ></DD ><DT ><TT CLASS="REPLACEABLE" ><I >domain_constraint</I ></TT ></DT ><DD ><P > New domain constraint for the domain. </P ></DD ><DT ><TT CLASS="REPLACEABLE" ><I >constraint_name</I ></TT ></DT ><DD ><P > Name of an existing constraint to drop or rename. </P ></DD ><DT ><TT CLASS="REPLACEABLE" ><I >NOT VALID</I ></TT ></DT ><DD ><P > Do not verify existing column data for constraint validity. </P ></DD ><DT ><TT CLASS="LITERAL" >CASCADE</TT ></DT ><DD ><P > Automatically drop objects that depend on the constraint. </P ></DD ><DT ><TT CLASS="LITERAL" >RESTRICT</TT ></DT ><DD ><P > Refuse to drop the constraint if there are any dependent objects. This is the default behavior. </P ></DD ><DT ><TT CLASS="REPLACEABLE" ><I >new_name</I ></TT ></DT ><DD ><P > The new name for the domain. </P ></DD ><DT ><TT CLASS="REPLACEABLE" ><I >new_constraint_name</I ></TT ></DT ><DD ><P > The new name for the constraint. </P ></DD ><DT ><TT CLASS="REPLACEABLE" ><I >new_owner</I ></TT ></DT ><DD ><P > The user name of the new owner of the domain. </P ></DD ><DT ><TT CLASS="REPLACEABLE" ><I >new_schema</I ></TT ></DT ><DD ><P > The new schema for the domain. </P ></DD ></DL ></DIV ><P> </P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN62988" ></A ><H2 >Notes</H2 ><P > Currently, <TT CLASS="COMMAND" >ALTER DOMAIN ADD CONSTRAINT</TT > and <TT CLASS="COMMAND" >ALTER DOMAIN SET NOT NULL</TT > will fail if the named domain or any derived domain is used within a composite-type column of any table in the database. They should eventually be improved to be able to verify the new constraint for such nested columns. </P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN62993" ></A ><H2 >Examples</H2 ><P > To add a <TT CLASS="LITERAL" >NOT NULL</TT > constraint to a domain: </P><PRE CLASS="PROGRAMLISTING" >ALTER DOMAIN zipcode SET NOT NULL;</PRE ><P> To remove a <TT CLASS="LITERAL" >NOT NULL</TT > constraint from a domain: </P><PRE CLASS="PROGRAMLISTING" >ALTER DOMAIN zipcode DROP NOT NULL;</PRE ><P> </P ><P > To add a check constraint to a domain: </P><PRE CLASS="PROGRAMLISTING" >ALTER DOMAIN zipcode ADD CONSTRAINT zipchk CHECK (char_length(VALUE) = 5);</PRE ><P> </P ><P > To remove a check constraint from a domain: </P><PRE CLASS="PROGRAMLISTING" >ALTER DOMAIN zipcode DROP CONSTRAINT zipchk;</PRE ><P> </P ><P > To rename a check constraint on a domain: </P><PRE CLASS="PROGRAMLISTING" >ALTER DOMAIN zipcode RENAME CONSTRAINT zipchk TO zip_check;</PRE ><P> </P ><P > To move the domain into a different schema: </P><PRE CLASS="PROGRAMLISTING" >ALTER DOMAIN zipcode SET SCHEMA customers;</PRE ><P></P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="SQL-ALTERDOMAIN-COMPATIBILITY" ></A ><H2 >Compatibility</H2 ><P > <TT CLASS="COMMAND" >ALTER DOMAIN</TT > conforms to the <ACRONYM CLASS="ACRONYM" >SQL</ACRONYM > standard, except for the <TT CLASS="LITERAL" >OWNER</TT >, <TT CLASS="LITERAL" >RENAME</TT >, <TT CLASS="LITERAL" >SET SCHEMA</TT >, and <TT CLASS="LITERAL" >VALIDATE CONSTRAINT</TT > variants, which are <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN > extensions. The <TT CLASS="LITERAL" >NOT VALID</TT > clause of the <TT CLASS="LITERAL" >ADD CONSTRAINT</TT > variant is also a <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN > extension. </P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="SQL-ALTERDOMAIN-SEE-ALSO" ></A ><H2 >See Also</H2 ><A HREF="sql-createdomain.html" >CREATE DOMAIN</A >, <A HREF="sql-dropdomain.html" >DROP DOMAIN</A ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="sql-alterdefaultprivileges.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="sql-alterextension.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >ALTER DEFAULT PRIVILEGES</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="sql-commands.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >ALTER EXTENSION</TD ></TR ></TABLE ></DIV ></BODY ></HTML >