41. How MySQL Optimizes DISTINCT? DISTINCT is converted to a GROUP BY on all columns and it will be combined with ORDER BY clause. SELECT DISTINCT t1.a FROM t1,t2 where Continue Reading »
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31. How can we get the number of rows affected by query? Number of rows can be obtained by SELECT COUNT (user_id) FROM users; (35)
21. How do you control the max size of a HEAP table? Maximum size of Heal table can be controlled by MySQL config variable called max_heap_table_size. 22. What is the Continue Reading »
11. Define REGEXP? REGEXP is a pattern match in which matches pattern anywhere in the search value. 12. Difference between CHAR and VARCHAR? Following are the differences between CHAR and Continue Reading »
1. What is MySQL? MySQL is an open source DBMS which is built, supported and distributed by MySQL AB (now acquired by Oracle) (54)