Subject How to create index for field in two tables and had any limitation
Author jeremylim2008
I am using firebird version 1.5, Delphi 7, bde and try to open tquery
with below sql statement.

"Select * From SalesOrder Left Join Customer on C.CustomerCode =
order by customername "

the customer records got 100, 000 records and sales order got around
one million records.
It took more than 2 minutes to open the query. as i know indexing will
improve a lots the speed
but indexing for 2 table I never try before.