<command>CREATE SEQUENCE</command> is is specified in <acronym>SQL:2003</acronym>.
<productname>PostgreSQL</productname> conforms with the standard, with the following exceptions:
<command>CREATE SEQUENCE</command> conforms to the <acronym>SQL</acronym>
standard, with the following exceptions:
<itemizedlist>
<listitem><para>The standard's <literal>AS <data type></literal> expression is not supported.</para></listitem>
<listitem><para>Obtaining the next value is done using the <function>nextval()</> function instead of the standard's <command>NEXT VALUE FOR</command> expression.</para></listitem>