C Function Definition - Analytics Database - Teradata Vantage

SQL External Routine Programming

Deployment
VantageCloud
VantageCore
Edition
Enterprise
IntelliFlex
VMware
Product
Analytics Database
Teradata Vantage
Release Number
17.20
Published
June 2022
Language
English (United States)
Last Update
2023-07-11
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iiv1628111441820.ditamap
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B035-1147
lifecycle
latest
Product Category
Teradata Vantage™
#define SQL_TEXT Latin_Text
#include <sqltypes_td.h>
#include <string.h>

void add_int (UDT_HANDLE *dynUDT,
              INTEGER    *result,
              int        *indicator_udt,
              int        *indicator_result,
              char        sqlstate[6],
              SQL_TEXT    extname[129],     
              SQL_TEXT    specific_name[129],
              SQL_TEXT    error_message[257])
{
   int Indicator=0;
   int  length = 0;
   int  sumValue=0;
   int AttributeIntValue = 0;
   char AttributeVCBuf[41];
   int AttributeVCInt=0;
   char AttributeLobBuf[41];
   int AttributeLobInt=0;
   LOB_LOCATOR AttributeLob;
   FNC_LobLength_t  StartLobLength;
   FNC_LobLength_t  MaxLobLength;
   FNC_LobLength_t  ActualLobLength;
   LOB_CONTEXT_ID LobCtx;
   UDT_HANDLE *UDT;
   int Attribute_count=0;
   int i;
   attribute_info_t dyn_attrinfo;

   strcpy((char *)sqlstate, "00000");
   memset(&(error_message[0]), 0, sizeof(error_message));

   /* This function takes a single Dynamic UDT parameter which is */
   /* permitted to have an arbitrary number of expressions passed */
   /* into it. Each expression is required to be one of:         */
   /*   - BYTEINT, SHORTINT, INTEGER value.                       */
   /*   - CHAR() string representing an integer value.            */
   /*   - VARCHAR() string representing an integer value.         */
   /*   - CLOB() string representing an integer value.            */

   /* Determine number of expressions passed into  */
   /* NEW VARIANT_TYPE Dynamic UDT constructor     */
   FNC_GetStructuredAttributeCount(*dynUDT, &Attribute_count);

   for(i=0; i<Attribute_count; i++)
   {
      /* Get data type information about the attribute being processed */
      FNC_GetStructuredAttributeInfo(*dynUDT, i,
         sizeof(attribute_info_t), &dyn_attrinfo);

      /* Process the value based upon the data type */
      switch(dyn_attrinfo.data_type)
      {
         case BYTEINT_DT:
         case SMALLINT_DT:
         case INTEGER_DT:
            AttributeIntValue = 0;          
            Indicator =0;
            /* Acquire the attribute value */
            FNC_GetStructuredAttribute(*dynUDT,
               &(dyn_attrinfo.attribute_name[0]), &AttributeIntValue,
               sizeof(INTEGER), &Indicator, &length);
            if (Indicator != 0)           // If NULL
               AttributeIntValue = 0;
            /* Process the value */
            sumValue = sumValue + AttributeIntValue;
            break;
         case VARCHAR_DT:
         case CHAR_DT:
            memset(&(AttributeVCBuf[0]), 0, sizeof(AttributeVCBuf));
            AttributeVCInt = 0;
            Indicator = 0;
            FNC_GetStructuredAttribute(*dynUDT,
               &(dyn_attrinfo.attribute_name[0]), &(AttributeVCBuf[0]),
               sizeof(AttributeVCBuf), &Indicator, &length);
            if (Indicator != 0)           // If NULL
               AttributeVCInt = 0;
            else
               AttributeVCInt = atoi(&(AttributeVCBuf[0]));
            /* Process the value */
            sumValue = sumValue + AttributeVCInt;
            break;
         case CLOB_REFERENCE_DT:
            memset(&(AttributeLobBuf[0]), 0, sizeof(AttributeLobBuf));
            AttributeLobInt = 0;
            Indicator = 0;
            FNC_GetStructuredInputLobAttribute(*dynUDT,
               &(dyn_attrinfo.attribute_name[0]),
               &Indicator, &AttributeLob );
            if (Indicator != 0)           // If NULL
               AttributeLobInt = 0;
            else
            {
               MaxLobLength = 41;
               StartLobLength = 0;
               FNC_LobOpen(AttributeLob, &LobCtx, StartLobLength,
                  MaxLobLength);
               FNC_LobRead(LobCtx, &(AttributeLobBuf[0]), MaxLobLength,
                  &ActualLobLength);
               FNC_LobClose(LobCtx);
               AttributeLobInt = atoi(&(AttributeLobBuf[0]));
            }

            sumValue = sumValue + AttributeLobInt;
            break;
         default:
            /* Invalid data type */
            strcpy((char *)sqlstate, "00023");
            sprintf(error_message,
               "\nBad data type passed in to Dynamic UDT");
            return;
            break;
      } /* end of the switch statement */
   }  /* end boundary for the for-attribute-processing-loop */
   *indicator_result = 0;    
   *result = sumValue;
   return;
}