For delete, insert or update queries, ingres_num_rows() returns the number of rows affected by the query. For other queries, ingres_num_rows() returns the number of rows in the query's result.
Note: This function is mainly meant to get the number of rows modified in the database. If this function is called before using ingres_fetch_array(), ingres_fetch_object() or ingres_fetch_row() the server will delete the result's data and the script won't be able to get them.
You should instead retrieve the result's data using one of these fetch functions in a loop until it returns false, indicating that no more results are available.
See also ingres_query(), ingres_fetch_array(), ingres_fetch_object() and ingres_fetch_row().