Sorry, I just realized that the fast and slow executions are included in each file. Compare the top one to the bottom one. You can see in the fast one that the execution plan starts by using "Where tblConsul.fldPlanKey=30472"

In the slower plan, the index on the temp table (IDX_TMP) isn't introduced until midway through the execution. This is after 7+ million rows have been queried to the right of this execution point.

So my question, which I understand may not be able to be answered, is why is a different table used to determine the filter in the two different cases AND, is there a way to prevent it or to let the optimizer know that there is a more efficient strategy?

ST