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MySQL performance question


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Hey all! What option do you think will scale better? To have 1 big select statement joining columns. Or multiple small queries to retreive the same information. Let me illustrate what I mean exaclty. Table2 and Table3 could have millions of records while, Table1 would only have thousands. The big select with Joining

SELECT table1.uri, table1.name, table2.random1, table2.random2, table3.something1, table3.something2FROM table1, table2, table3WHERE table1.id = 1 AND table2.id = 1 AND table3.id = 1

Multi small queries

SELECT uri, name FROM table1 WHERE id = 1SELECT random1, random2 FROM table2 WHERE id = 1SELECT something1, something2 FROM table3 WHERE id = 1

Thanks!

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One bigger query is always preferable. However, you should use appropriate LIMIT clauses whenever that makes sense, so that each subquery can be as fast as possible and deliver only what's needed.So for example, if you're only displaying the first 100 records, adding "LIMIT 100" at the very end is not just a nice to have, but a must.

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