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)
