DataDirect Connect for ODBC User's Guide and Reference

rc = SQLColumns (... "UnknownTable" ...);
// This call to SQLColumns will generate a query to the
// system catalogs... possibly a join which must be
// prepared, executed, and produce a result set
rc = SQLBindCol (...);
rc = SQLExtendedFetch (...);
// user must retrieve N rows from the server
// N = # result columns of UnknownTable
// result column information has now been obtained
// prepare dummy query
rc = SQLPrepare (... "SELECT * from UnknownTable
WHERE 1 = 0" ...);
// query is never executed on the server - only prepared
rc = SQLNumResultCols (...);
for (irow = 1; irow <= NumColumns; irow++) {
rc = SQLDescribeCol (...)
// + optional calls to SQLColAttributes
}
// result column information has now been obtained
// Note we also know the column ordering within the table!
// This information cannot be
// assumed from the SQLColumns example.