Umbuzo we-SQL wokunquma uhlu lwezinga08
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Namuhla ngithole lo msebenzi olandelayo ngenkathi ngisebenza kuphrojekthi yamakhasimende: Thatha itafula le-SQL "umsebenzisi" ngamakholomu "id" kanye "nesikolo" bese unquma isikhundla sabo bonke abasebenzisi ngokususelwa ku- "score" lapho abasebenzisi abane- thola isilinganiso esifanayo ngesikolo esifanayo. Lo msebenzi ungaxazululwa intuitively futhi kalula ngokusebenzisa okuguquguqukayo okuchazwe ngumsebenzisi .

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CREATE TABLE
    user(id INT, score INT);
INSERT INTO
    user(id, score)
VALUES
    (1, 10), (2, 40), (3, 55), (4, 10), (5, 5), (6, 20), (7, 30), (8, 70), (9, 30)

Kusetshenziswa okuguqukayo okubili kukuxazulula lokhu kalula

SET @score_prev = NULL;
SET @cur_rank = 0;
SELECT id, score, CASE
    WHEN @score_prev = score THEN @cur_rank
    WHEN @score_prev := score THEN @cur_rank := @cur_rank + 1
END AS rank
FROM user
ORDER BY score DESC

futhi uthola umphumela owufunayo

+--------+-----------+----------+
|  *id*  |  *score*  |  *rank*  |
|    8   |      70   |      1   |
|    3   |      55   |      2   |
|    2   |      40   |      3   |
|    7   |      30   |      4   |
|    9   |      30   |      4   |
|    6   |      20   |      5   |
|    1   |      10   |      6   |
|    4   |      10   |      6   |
|    5   |       5   |      7   |
+--------+-----------+----------+