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There are several DBEngines are available for MySQL DB. Currently I'm using InnoDB. My actual problem is, I have a table that consist of millions of data. Therefore the select queries that given to this table is extremely slow. I need to know which configuration should I use to make the select query faster, that doesn't affects the speed of insertion.

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Your problem is not the DB Engine, but the lack of the indices. Indices make possible for your database to find things (records) much faster. You had to make some.

I suggest to read an sql indexing tutorial (google is your friend), and then come back with a new question, if you have yet one.

Extension after you gave your query: in this case there is two problem. First, LIMIT isn't really simple to make faster with indices. But it is not a big problem, because in your query is it visible, what is the cause of the sloooow query. It is the multiple inequality conditions in the WHERE. I didn't give a medal for the liferay programmers for this sh... sometimes-maybe-not-really-useful solution.

The greatest problem is, that such indices can't be make faster by indices easily. On big tables they should be avoided, if we want to develop high-quality software.

The solution - indexing a table for multiple inequality search term - isn't known currently also for me, thus I opened a new question for you, what can be done in MySQL in your problem. Maybe we get some interesting answer and in this case I will be able to extend also this question.

  • my query is "select * from school_liferay.trip_parameters where speed>5 and lattitude<100 limit 10;" it takes 265.9541s . Now i created an index with column speed and latitude but it is also taking the same time to query data. – Joyal George May 27 '14 at 13:15
  • In general > and < are not so fast as = or <> because such selects produce large or even huge temporary tables that sometimes can't fit into memory and placed on disk by mysql engine. That's the main cause of poor performance. – Kondybas May 27 '14 at 22:09
  • @Kondybas There is an alternative problem as well. If there is two non-equality term in a search condition, it can't be indexed with simple record-trees. – peterh - Reinstate Monica May 28 '14 at 8:25

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