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Forum Newbie
Group: Forum Members
Last Login: 11/28/2008 7:01:15 AM
Posts: 8,
Visits: 12
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Can someone give me an example for a very simple UDF. I just want to have the C-code and the definition of the function.
Name: UDF_Multiplyby2()
Input: Decimal(15,2)
Output: Decimal(15,2)
To do: Multiply Input by 2, that's all.
Teradata gives me always a stack error.
I'm using DECIMAL8 as in- and output.
Thank's a lot,
Koen.
AXA Belgium
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Supreme Being
Group: Forum Members
Last Login: 10/7/2008 12:54:51 PM
Posts: 116,
Visits: 20
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you have to increase the output lenght. leave the input as is decimal (15,2)
so the largest number you can provide is
9999999999999.99
set the output: Decimal(18,2) {I guess 18 is the max that is allowed}
and when you do the multiplication use the cast function
output = cast(input * 2 as decimal(18,2))
this should work.
please let me know if it does not work.
Feroz Shaik
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Supreme Being
Group: PAC and SFT Members
Last Login: Today @ 6:11:07 PM
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Note that though the logic inside the function body may be "simple", you can't code the prototype as a "simple C function". In other words,
DECIMAL8 *udf_m_2(DECIMAL8 *in_val){...}
will not work.
If you register the function as
CREATE FUNCTION UDF_Multiplyby2(InVal DECIMAL(15,2)) RETURNS DECIMAL(15,2)
... PARAMETER STYLE TD_GENERAL ... EXTERNAL NAME ... !udf_m_2'
Then the function prototype would be something like
void *udf_m_2(DECIMAL8 *in_val, DECIMAL8 *result, char sqlstate[6])
or for PARAMETER STYLE SQL
void *udf_m_2(DECIMAL8 *in_val, DECIMAL8 *result,
int *in_val_NULL_indicator, int *result_NULL_indicator, char sqlstate[6],
SQL_TEXT extname[129],
SQL_TEXT specific_name[129],
SQL_TEXT error_message[257])
Then note that DECIMAL8 is a struct with a 32-bit unsigned and 32-bit signed integer. You may want to convert that to a native 64-bit integer type.
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