MySQL - how long to create an index?
        Posted  
        
            by user293594
        on Stack Overflow
        
        See other posts from Stack Overflow
        
            or by user293594
        
        
        
        Published on 2010-03-20T13:35:56Z
        Indexed on 
            2010/03/20
            13:41 UTC
        
        
        Read the original article
        Hit count: 405
        
Can anyone tell me how adding a key scales in MySQL? I have 500,000,000 rows in a database, trans, with columns i (INT UNSIGNED), j (INT UNSIGNED), nu (DOUBLE), A (DOUBLE). I try to index a column, e.g.
ALTER TABLE trans ADD KEY idx_A (A);
and I wait. For a table of 14,000,000 rows it took about 2 minutes to execute on my MacBook Pro, but for the whole half a billion, it's taking 15hrs and counting. Am I doing something wrong, or am I just being naive about how indexing a database scales with the number of rows?
© Stack Overflow or respective owner