Reducing execution time of MySQL UPDATE -

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i want optimize execution time (50 sec) of following update command.

    update matches     join players b      on a.player1_name = b.player_name     set a.player1_id = b.id     a.player1_id = 0

the table matches has approximately 10000 entries , table players 4000 entries.

make sure have indexes on a.player1_name, b.player_name , a.player1_id.


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