Row Count (-RC or -ROWCNT)

For ODBC, Oracle, DB2® for Windows, and DB2 for UNIX adapters only.

Use the Row Count adapter command (-ROWCNT) to specify the number of rows to be retrieved in one fetch from the database by the database adapter. This command can be used for a source or in a DBLOOKUP, DBQUERY, or GET function.

This adapter command specifies the number of rows that the adapter should retrieve from the database. It should not be confused with the FetchAs > FetchUnit card setting that specifies the number of rows the adapter will pass to the Command Server. For more information about the FetchUnit card setting, refer to the Database Interface Designer documentation.

The time to fetch is optimized in accordance with the increase in the number of rows to be retrieved. Therefore, a significant performance improvement may be gained by retrieving as many rows as possible in a single fetch. The number of rows to be retrieved is limited by the memory requirement, because the return buffer must be large enough to hold the rows that are retrieved.

-ROWCNT row_count

Without using this command, the default number of rows to be retrieved per fetch is:

  • for ODBC, one row
  • for DB2, one row
  • For Oracle, a 64K buffer is allocated. Then, a calculation is performed to determine the number of rows that can be held in the buffer.