redhat man page for create_conversion

CREATE 
CONVERSION(7)						   SQL Commands 					      CREATE CONVERSION(7)

NAME
       CREATE CONVERSION - define a user-defined conversion

SYNOPSIS
       CREATE [DEFAULT] CONVERSION conversion_name
	   FOR source_encoding TO dest_encoding FROM funcname

DESCRIPTION
       CREATE  CONVERSION defines a new encoding conversion. Conversion names may be used in the CONVERT() function to specify a particular encod-
       ing conversion. Also, conversions that are marked DEFAULT can be used for automatic encoding conversion between frontend and  backend.  For
       this purpose, two conversions, from encoding A to B AND from encoding B to A, must be defined.

       To be able to create a conversion, you must have the execute right on the function and the create right on the destination schema.  "PARAM-
       ETERS"

       DEFAULT
	      The DEFAULT clause indicates that this conversion is the default for this particular source to destination encoding. There should be
	      only one default encoding in a schema for the encoding pair.

       conversion_name
	      The  name  of  the  conversion.  The conversion name may be schema-qualified. If it is not, the conversion is defined in the current
	      schema. The conversion name must be unique within a schema.

       source_encoding
	      The source encoding name.

       source_encoding
	      The destination encoding name.

       funcname
	      The function used to perform the conversion. The function name may be schema-qualified. If it is not, the function will be looked up
	      in the path.

	      The function must have the following signature:

		   conv_proc(
		   INTEGER,  -- source encoding id
		   INTEGER,  -- destination encoding id
		   CSTRING,  -- source string (null terminated C string)
		   CSTRING,  -- destination string (null terminated C string)
		   INTEGER	  -- source string length
		   ) returns VOID;

NOTES
       Use DROP CONVERSION to remove user-defined conversions.

       The privileges required to create a conversion may be changed in a future release.

EXAMPLES
       To create a conversion from encoding UNICODE to LATIN1 using myfunc:

       CREATE CONVERSION myconv FOR 'UNICODE' TO 'LATIN1' FROM myfunc;

COMPATIBILITY
       CREATE CONVERSION is a PostgreSQL extension.  There is no CREATE CONVERSION statement in SQL99.

SEE ALSO
       CREATE FUNCTION [create_function(7)], DROP CONVERSION [drop_conversion(7)], PostgreSQL Programmer's Guide

SQL - Language Statements					    2002-11-22						      CREATE CONVERSION(7)