Hi Sergey,

>My intention was to avoid double JOIN for the person and referral tables reported by SYS(3054,11) for previous query and see if it improver performance.

switching from 3 stage to 2 stage join was also my intention in my first post. Going via separate statements is less elegant, but (at least for me <g>) better grokable by checking on all sets / tables involved.

Having a compound index usable for both checks defined for the join to take place should be the fastest way in more than a few scenarios. But how to code in SQL usable for the vfp planner ?

My first "naive" attempt would be to use scans as I believe vfp to swith over to cartesian join if joined on "Between" the range specified by cl_REf and minimum date as calculated and cl_REF and possible maximum date. But a "Between" SQL should also be checked.


regards

thomas