This reverts commit f4e3022fbdecc25a22ae6eaf072e462aa6695f35.
The commit apparently caused MCOL-5318 and MCOL-5319 which involve the
internal ColumnStore batch insert mechanism passing through the SQL
layer. The code block involved in this change is a predicate checking
for the HWM extent in WriteEngineServer at the end of the batch insert.
This is done in WE_DMLCommandProc::processBatchInsertHwm(). The original
predicate check in this function for the HWM extent is restored until
further investigation.