16.20 - Example: Aggregate Function with Parameter Style TD_GENERAL - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - SQL External Routine Programming

Product
Advanced SQL Engine
Teradata Database
Release Number
16.20
Release Date
April 2020
Content Type
Programming Reference
Publication ID
B035-1147-162K
Language
English (United States)

This aggregate function declaration uses parameter style TD_GENERAL:

/*****  C source file name: STD_DEV.c  *****/
   
#define SQL_TEXT Latin_Text
#include <sqltypes_td.h>
#include <string.h>
#include <math.h>
void STD_DEV ( FNC_Phase     phase,
               FNC_Context_t *fctx,
               FLOAT         *x,
               FLOAT         *result,
               char          sqlstate[6] )
{
     ...
}

The corresponding CREATE FUNCTION statement looks like this:

CREATE FUNCTION STD_DEV(x FLOAT)
RETURNS FLOAT
CLASS AGGREGATE
LANGUAGE C
NO SQL
PARAMETER STYLE TD_GENERAL
EXTERNAL;