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Editorial Team
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Asked: 2026-05-22T01:48:25+00:00

I would like to optimize this query using SQLite 3. SELECT id FROM Table

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I would like to optimize this query using SQLite 3.

SELECT id FROM Table WHERE value = (SELECT max(value) FROM Table WHERE value < myvalue )
   UNION 
SELECT id FROM Table WHERE value = (SELECT min(value) FROM Table WHERE value > myvalue );

I want the 2 closest id from a given value. Example: id 20, value 50. The closest id could be 3 with the value 48 (max value inferior) and above id 4 with value 55 (min value superior).

SQLite 3 has not all the features of a real database, if you have something better I can use, well thanks !

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1 Answer

  1. Editorial Team
    SELECT
 (SELECT id FROM test WHERE value < myvalue ORDER BY value DESC LIMIT 1) as below,
 (SELECT id FROM test WHERE value > myvalue ORDER BY value ASC  LIMIT 1) as above;

    Theorically speaking this should be faster becase it use two table scans intead of four.
    Anyway i would create a table with a few millon records and test different queries with
    the timer on. (.timer ON in sqlite console).

    Also make sure to test with and without an index on value. Sometimes, specially
    when the index size if bigger than your memory, indexes are useless.

    If speed is the real issue consider an alternative light storage, like Kyoto
    Cabinet.

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