svanderclock wrote:

> I just discover something interesting :
>
> you can also use the build in function substr instead of aludf_copy it's the same result..
>
> if the declaration is
>
> DECLARE EXTERNAL FUNCTION substr
> CSTRING(32744) CHARACTER SET ISO8859_1,
> SMALLINT,
> SMALLINT
> RETURNS CSTRING(32744) CHARACTER SET ISO8859_1 FREE_IT
> ENTRY_POINT 'IB_UDF_substr' MODULE_NAME 'ib_udf';
>
> Time to execute the sql: 827 ms

My guess is that once you go over the size limit for VARCHAR, BLOBs are
used instead, and BLOB handling is much slower.

BTW, I'm surprised that engine did not reject such UDF declaration.

--
Milan Babuskov

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