> I am working in an older version of IB that does not have the GEN_UUID()
> function, so I am working on implementing the function as a UDF, but it is
> giving me an "arithmetic exception, numeric overflow, or string truncation".
> I looking at the FB source to see how it is implemented there, but internal
> functions are implemented in noticeably different ways then an UDF.
>
> Here is what I got:
>
> char* EXPORT fn_GEN_UUID()
> {
> int size = sizeof(GUID) + 1;
> GUID *guidBuff = (GUID*) ib_util_malloc(size);
> ::ZeroMemory(guidBuff, size);
>
> ::CoCreateGuid(guidBuff);
>
> return (char *) guidBuff;
> }
>
> /* --------------------------------- */
>
> DECLARE EXTERNAL FUNCTION GEN_UUID
> RETURNS CHAR(16) FREE_IT
> ENTRY_POINT 'fn_GEN_UUID' MODULE_NAME 'UDF_GEN_UUID';
>
> CREATE DOMAIN UNIQUEIDENTIFIER AS
> CHAR(16) CHARACTER SET OCTETS
> NOT NULL COLLATE OCTETS;
>
> CREATE TABLE TEST_UUID
> (
> PKID INTEGER NOT NULL,
> UUID_VALUE UNIQUEIDENTIFIER
> );
>
> /* --------------------------------- */
>
> INSERT INTO TEST_UUID ( PKID, UUID_VALUE) VALUES ( 1, GEN_UUID());
Before re-inventing the wheel, there are UDF libraries out there, which
have something like that. I guess FreeAdhocUDF for example.
--
With regards,
Thomas Steinmaurer
* Upscene Productions - Database Tools for Developers
http://www.upscene.com/
* My Blog
http://blog.upscene.com/thomas/index.php
* Firebird Foundation Committee Member
http://www.firebirdsql.org/en/firebird-foundation/
