Thank you, the penny finally dropped :)

>I do belive that TIME(start) caused the problem because the index key would evaluate to new value each time it was calcualted.
>
>>
>>I have since tried it with your solution and with ALSO with the EMPNO+DTOS(DATE)+DUTY+EXCCODE+STRTRAN(SUBSTR(TTOC(START),12,5),":").
>>Both do not display the phantom record now.
>>
>>I can only assume that the index was corrupt... though I am sure I did try PACK and REINDEX before. I cannot duplicate the problem anymore. This could be because I physically deleted the CDX and started afresh (?)
>>
>>My argument has been, throughout this thread, is that, even if the expression was incorrect, as long as it evaluated to a legal expression (which it would have to), why the phantom record..
>>
>>Sorry for the back and forth, I am really curious to understand what causes this problem.
>>