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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B035-1147
lifecycle
latest
Product Category
Teradata Vantage™
#define SQL_TEXT Latin_Text
#include <sqltypes_td.h>
#include <string.h>
#define buffer_size 100000
const char trunc_err[6] = "22001";
static int append_lob(LOB_RESULT_LOCATOR, LOB_LOCATOR);
void concat3( LOB_LOCATOR         *a,
              VARBYTE             *b,
              LOB_LOCATOR         *c,
              LOB_RESULT_LOCATOR  *result,
              char                sqlstate[6] )
{
   FNC_LobLength_t actlen;
   /* Append the first argument. Note that a truncation error could
      occur only if the result exceeds the maximum LOB size, so the
      first append should never get that error.
    */
   if (append_lob(*result, *a) != 0)
   {
      strcpy(sqlstate, trunc_err);
      return;
   }
   /* Append the second argument */
   if (FNC_LobAppend(*result, b->bytes, b->length, &actlen) != 0)
   {
      strcpy(sqlstate, trunc_err);
      return;
   }
   /* Append the third argument */
   if (append_lob(*result, *c) != 0)
   {
      strcpy(sqlstate, trunc_err);
      return;
   }
}
int append_lob( LOB_RESULT_LOCATOR dest,
                LOB_LOCATOR source )
{
   BYTE buffer[buffer_size];
   LOB_CONTEXT_ID id;
   FNC_LobLength_t actlen;
   int trunc_err = 0;
   FNC_LobOpen(source, &id, 0, 0);
   while( FNC_LobRead(id, buffer, buffer_size, &actlen) == 0 &&
            !trunc_err )
      trunc_err = FNC_LobAppend(dest, buffer, actlen, &actlen);
   FNC_LobClose(id);
   return trunc_err;
}