Question

If I try to delete a brunch of data from a table. say

DELETE FROM myTable Where CreationDate < GetDate()

that takes hours to be deleted, will this table be locked and no new insert can happened?

This table doesn’t self reference itself. I would assume I can still insert new data while it is deleting. Will the delete sql uses an exclusive lock that prevents all access to the table?

Thanks

Answer 1

You can batch them to prevent it from locking the whole table:

WHILE 1 = 1
  BEGIN
        DELETE  TOP 10000 FROM  myTable WHERE CreationDate < GetDate()

        IF @@ROWCOUNT = 0
            BREAK
  END