Hello Sergey,

Yes we made the delete without sp_execute and we also change the Delete for a select and studied the execution plan and we have clustered index seek.

From studying the execution plan, it looks like our problem come from updating the clustered index.

For each row, 76% of the cost is for updating the indexes.

We already tried to drop the cluster index but removing the indexes was even slower.

What else can we try?

Thanks,

ERic.