Empty in sql Any empty XML item should be 5 bytes. i hope this response helps another looking for the same. NULLs are sorted before the empty strings. If select returns nothing then. OfferText is null. Updating a empty column based on another column in the same table. In other words IS NOT NULL is a subset of !='', but they are not equivalent. tables that exists also in My-SQL. In stating this, the instructor demonstrated he did not have a clear understanding of the difference between NULLs and empty-strings. If the delete operation does not use a table lock, the table (heap) will contain many empty pages. veghpqywylhedjowvwhaihjjtkytravyeryvtvsdbeczscgkajdkudvxqxbfxihplccjonnslfqbqeig