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There isn't much out there for MySQL except the following: EXPLAIN EXTENDED followed by SHOW WARNINGS SHOW PROFILES (Older Releases of MySQL) MySQL PERFORMANCE_SCHEMA Read these carefully, see what you think ...


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You have not defined any indexes, so this query would be slow even without sorting, because it needs a full table scan. You should define a combined index on (uid, id). The first part helps in finding all rows WHERE uid = X. If these have been found, the second part can be used to sort the result set without the need to use filesort. Use this create table ...


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This: SET SHOWPLAN_XML ON; GO SELECT * FROM sys.objects; GO Is equivalent to pressing Display Estimated Execution Plan on the toolbar (or hitting Ctrl + L). You'll notice that no rows are returned from the query, like there is when you use Include Actual Execution Plan (Ctrl + M). The spill warning is only a runtime warning. There is no way that SQL ...



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