Is it possible to insert multiple rows at a time in an SQLite database?

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猫巷女王i
猫巷女王i 2020-11-21 06:12

In MySQL you can insert multiple rows like this:

INSERT INTO \'tablename\' (\'column1\', \'column2\') VALUES
    (\'data1\', \'data2\'),
    (\'data1\', \'da         


        
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  •  时光取名叫无心
    2020-11-21 06:57

    update

    As BrianCampbell points out here, SQLite 3.7.11 and above now supports the simpler syntax of the original post. However, the approach shown is still appropriate if you want maximum compatibility across legacy databases.

    original answer

    If I had privileges, I would bump river's reply: You can insert multiple rows in SQLite, you just need different syntax. To make it perfectly clear, the OPs MySQL example:

    INSERT INTO 'tablename' ('column1', 'column2') VALUES
      ('data1', 'data2'),
      ('data1', 'data2'),
      ('data1', 'data2'),
      ('data1', 'data2');
    

    This can be recast into SQLite as:

         INSERT INTO 'tablename'
              SELECT 'data1' AS 'column1', 'data2' AS 'column2'
    UNION ALL SELECT 'data1', 'data2'
    UNION ALL SELECT 'data1', 'data2'
    UNION ALL SELECT 'data1', 'data2'
    

    a note on performance

    I originally used this technique to efficiently load large datasets from Ruby on Rails. However, as Jaime Cook points out, it's not clear this is any faster wrapping individual INSERTs within a single transaction:

    BEGIN TRANSACTION;
    INSERT INTO 'tablename' table VALUES ('data1', 'data2');
    INSERT INTO 'tablename' table VALUES ('data3', 'data4');
    ...
    COMMIT;
    

    If efficiency is your goal, you should try this first.

    a note on UNION vs UNION ALL

    As several people commented, if you use UNION ALL (as shown above), all rows will be inserted, so in this case, you'd get four rows of data1, data2. If you omit the ALL, then duplicate rows will be eliminated (and the operation will presumably be a bit slower). We're using UNION ALL since it more closely matches the semantics of the original post.

    in closing

    P.S.: Please +1 river's reply, as it presented the solution first.

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