Improve documentation about foreign data wrapper validator functions.

Modified version of a patch by Shigeru Hanada.
This commit is contained in:
Tom Lane 2011-07-05 15:38:18 -04:00
parent 2683a6340d
commit 8b6c89ad13

View File

@ -38,14 +38,20 @@
</para> </para>
<para> <para>
The validator function is responsible for validating options given in the The validator function is responsible for validating options given in
<command>CREATE FOREIGN DATA WRAPPER</command>, <command>CREATE <command>CREATE</command> and <command>ALTER</command> commands for its
SERVER</command> and <command>CREATE FOREIGN TABLE</command> commands. foreign data wrapper, as well as foreign servers, user mappings, and
foreign tables using the wrapper.
The validator function must be registered as taking two arguments, a text The validator function must be registered as taking two arguments, a text
array containing the options to be validated, and an OID representing the array containing the options to be validated, and an OID representing the
type of object the options are associated with (in the form of the OID type of object the options are associated with (in the form of the OID
of the system catalog the object would be stored in). If no validator of the system catalog the object would be stored in, either
function is supplied, the options are not checked at object creation time. <literal>ForeignDataWrapperRelationId</>,
<literal>ForeignServerRelationId</>,
<literal>UserMappingRelationId</>,
or <literal>ForeignTableRelationId</>).
If no validator function is supplied, options are not checked at object
creation time or object alteration time.
</para> </para>
<para> <para>