Some SQL problems that make people scratching their head, esProc is OK, but you need to change the original programming habits, which is actually not easy, A drawback is that the SQL provided by esProc is not comprehensive enough, it is only a subset of SQL92. There are no problems with regular ones, including subqueries and WITH. However, EXISTS is not yet supported, and there is no window function available. Of course, there may be more, and I am still trying