Data binding

Before converting to Informix ODS, our main database platform was SQLBase. In the SQLBase world, we noticed that the optimizer sometimes took different paths depending upon the query you submit. For instance, take the two examples below: Ex1: select name, phone_number from customer where name = 'JOHNSON'; Ex2: select name, phone_number from customer where name = :BindVariable; Ex1 explicity lists the literal value. Ex2 uses a bind variable. Q: When a query is submitted and goes through the Prepare and Compile steps, does the optimizer treat the two queries differently? same? Q: Are factors such as selectivity and distributions affected when Bind Variables are used? Q: When the does the value of the Bind Variable get resolved? Q: Does your answer change depending on your communication layer, ODBC vs Native drivers? Because of our SQLBase days, we have taken the direction of avoiding bind variables when going against our Informix ODS. SteveR -- ----------------------------------------------------------------- Steve Romankiw + Executive Risk Inc. + DBA + email: sromankiw@execrisk.com 82 Hopmeadow Street + work: (860) 408-2474 Simsbury,CT 06070 + fax: (860) 408-2139 -----------------------------------------------------------------