Yes, you can, using an expression index CREATE INDEX IDX_MYINDEX ON MY_TABLE COMPUTED BY (INVOICED - RECEIVED);
and your SELECT would be: SELECT * FROM MY_TABLE WHERE INVOICED - RECEIVED < 0 That way you will not need to create an additional column neither to do an UPDATE neither to create a trigger. Greetings. Walter. On Tue, Sep 13, 2016 at 9:26 AM, Maya Opperman m...@omniaccounts.co.za [firebird-support] <firebird-support@yahoogroups.com> wrote: > > > Hi, > > > > I have a large table, and I’m only extracting a few records using: > > > > Select t.ID > > From my_table t > > Where t.Invoiced < t.Received > > > > Invoice and received are of type decimal(18,5) > > > > IBExpert is reporting these as unindexed reads. > > > > Is there an index I could create to speed up the loading? > > > > Thanks in advance > > Maya > > > > > > >
