Here is the SQL that fails in IB_SQL's DSQL applied to a Firebird 1.5
table - dialect 3, I believe:

SELECT min(id) from trays where tray_no = :aTray INTO :Id;

Doesn't matter where I place the INTO.

'id' is the primary key but substituting a different field yields the
same results.

Very puzzled since this is an equivalent (syntax-wise) SQL statement
from an Interbase book.

Thank you for any interest in this matter.

Pete