The documentation for PQexecPrepared says:
(There is not currently a provision to obtain different result columns in different formats, although that is
possiblein the underlying protocol.)
Would anyone be interested in a patch to allow this?
I could, for example, change PQsendQueryGuts to do something like:
static int PQsendQueryGuts( PGconn *conn, const char *command,
constchar *stmtName, int nParams, const Oid *paramTypes,
const char *const *paramValues, const int *paramLengths,
const int *paramFormats, int resultFormat, ... ) /* Add this last
argument.*/
{ ...
if ( resultFormat == -1 ) { /* or == nParams, perhaps? */ va_list args; const int *resultFormats;
va_start( args, resultFormat ); resultFormats = va_arg( args, const int * ); va_end( args );
if ( pqPutInt( nParams, 2, conn ) < 0 ) goto sendFailed; for ( i = 0; i < nParams; i++ )
if ( pqPutInt( resultFormats[i], 2, conn ) < 0 ) goto sendFailed; } /* This is what libpq does
already.*/ else if ( pqPutInt( 1, 2, conn ) < 0 || pqPutInt( resultFormat, 2, conn ) ) goto
sendFailed;
...
}
And then teach the other API functions (PQexecParams, PQsendQueryParams,
PQsendQueryPrepared) to accept and pass on the extra ... argument. That
wouldn't break existing code, and new users could set resultFormat to
invoke the new behaviour. It seems a bit ugly, but on the other hand,
it doesn't seem worthwhile to add a new interface for this behaviour.
Thoughts?
-- ams