I\'m trying to test / improve an sql query for sp开发者_高级运维eed however caching is not showing me the true speed.
I need some help optimizing a MSSQL view that is, honestly, a little too much complex for my knowledge.
Can I optimize this query, or modify the table structure in order to shorten the execution time? I don\'t really understand the output of EXPLAIN. Am I missing some index?
I\'m writing a query like this: select * from myTable where X in (select X from Y) and XX in (select X from Y)
This question already has answers here: SQL left join vs multiple tables on FROM line? (12 answers) Closed 8 years ago.
I\'m currently trying to improve the speed of SELECTS for a MySQL table and would appreciate any suggestions on ways to improve it.
I\'m trying to understand how no_index actually speeds up a query and haven\'t been able to find documentation online to explain it.
if it\'s known that there are only two values to candidate for the result of a column, ifnull(a, b) as a_or_b_1
Example Data: $address_1= \'123 Main St.\'; $address_2= \'Suite 200\'; $phone= \'1235551212\'; $zip= \'12345\';
I hav开发者_运维百科e a left join statement on 2 tables: tbl1 has about 1 million records and tbl2 has about 20 million. The query takes about 9 seconds to execute. I have indexes on both but somethin
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