CREATE CONVERSION
Name
CREATE CONVERSION -- define a new encoding conversion
Synopsis
CREATE [DEFAULT] CONVERSION
name
FOR
source_encoding
TO
dest_encoding
FROM
funcname
Description
CREATE CONVERSION defines a new conversion between character set encodings. Conversion names may be used in the convert function to specify a particular encoding conversion. Also, conversions that are marked DEFAULT can be used for automatic encoding conversion between client and server. 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 EXECUTE privilege on the function and CREATE privilege on the destination schema.
Parameters
-
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.
-
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.
-
dest_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)
internal, -- destination (fill with a 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 UTF8 to LATIN1 using myfunc:
CREATE CONVERSION myconv FOR 'UTF8' TO 'LATIN1' FROM myfunc;
Compatibility
CREATE CONVERSION is a PostgreSQL extension. There is no CREATE CONVERSION statement in the SQL standard.
