I have solved all my problems except this one. And, of course, it won't happen while I'm tracing it. I don't know if this has something to do with the nature of the problem or just my bad luck. Any way, in tracing through the code, in the validatefield method, the alias is closed and reopened. This always works OK while I'm tracing through the code, but it is the only place the table is being closed. Do you have any ideas on how I could pin this down?

The call stack is :

sdtdbcxmgr.validate
dbcxmgr.validate
sdtdbcxmgr.osdtmgr.validate
basemgr.validate
sdtdbcxmgr.osdtmgr.validatefield