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-$PostgreSQL: pgsql/doc/src/sgml/ref/create_domain.sgml,v 1.22 2005/05/02 01:52:50 neilc Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/create_domain.sgml,v 1.23 2005/09/22 23:56:46 momjian Exp $
PostgreSQL documentation
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</para>
<para>
- Domains are useful for abstracting common fields between tables into
- a single location for maintenance. For example, an email address column may be used
- in several tables, all with the same properties. Define a domain and
- use that rather than setting up each table's constraints individually.
+ Domains are useful for abstracting common fields between tables
+ into a single location for maintenance. For example, an email address
+ column may be used in several tables, all with the same properties.
+ Define a domain and use that rather than setting up each table's
+ constraints individually. <note>Keep in mind also that declaring a
+ function result value as a domain is pretty dangerous, because none of
+ the PLs enforce domain constraints on their results.</note>
</para>
</refsect1>