After executing a DSQL SELECT, a call to isc_dsql_sql_info() returns 0
for the isc_info_req_select_count value. However, a call to
isc_dsql_sql_info() after the subsequent isc_dsql_fetch() returns a
value indicating the row number in the result set being fetched.
Since, isc_dsql_fetch() performs sequential access, this value is
always exactly one greater than the previous call.

For my purposes, this is not very useful information.

Is this intentional? Is there any way after a SELECT has been
executed to obtain the number of rows in the result set (without
fetching each one)?