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? ??? ??? MySQL ???? MySQL?? ANSI SQL RANK ??? ???? ??? ??????

MySQL?? ANSI SQL RANK ??? ???? ??? ??????

Jan 24, 2025 am 05:02 AM

How to Replicate the ANSI SQL RANK Function in MySQL?

MySQL?? ANSI SQL RANK ?? ?????

SQL?? RANK ??? ??? ??? ???? ??? ?? ??? ?????? ? ?????. ??? ??? ??? ???? ??? ????? ?? ANSI SQL ??? ??? ? ????. 

SELECT RANK() OVER (PARTITION BY Gender ORDER BY Age) AS [Partition by Gender], FirstName, Age, Gender FROM Person

??? MySQL?? ? ??? ??? RANK ??? ????? ??? ??? ????. MySQL?? ??? ??? ???? ? ?? ??? ??? ????.

? ?? ??? ??? ?? ?? ??? ???? ????. 

SELECT    first_name,
          age,
          gender,
          @curRank := @curRank + 1 AS rank
FROM      person p, (SELECT @curRank := 0) r
ORDER BY  age;

(SELECT @curRank := 0) ??? ??? ??? SET ?? ?? ??? ????? ????.

Person ???? ???? ?? ?? ???? ??? ??? ??????. 

CREATE TABLE person (id int, first_name varchar(20), age int, gender char(1));

INSERT INTO person VALUES (1, 'Bob', 25, 'M');
INSERT INTO person VALUES (2, 'Jane', 20, 'F');
INSERT INTO person VALUES (3, 'Jack', 30, 'M');
INSERT INTO person VALUES (4, 'Bill', 32, 'M');
INSERT INTO person VALUES (5, 'Nick', 22, 'M');
INSERT INTO person VALUES (6, 'Kathy', 18, 'F');
INSERT INTO person VALUES (7, 'Steve', 36, 'M');
INSERT INTO person VALUES (8, 'Anne', 25, 'F');

MySQL ??? ???? ? ?? ??? ??? ???? ?? ??? ??? ??? ?? ??? ?? ? ????. 

<code>+------------+------+--------+------+
| first_name | age  | gender | rank |
+------------+------+--------+------+
| Kathy      |   18 | F      |    1 |
| Jane       |   20 | F      |    2 |
| Nick       |   22 | M      |    3 |
| Bob        |   25 | M      |    4 |
| Anne       |   25 | F      |    5 |
| Jack       |   30 | M      |    6 |
| Bill       |   32 | M      |    7 |
| Steve      |   36 | M      |    8 |
+------------+------+--------+------+
8 rows in set (0.02 sec)</code>

? ??? ???? MySQL? RANK ??? ???? ?? ???? ??? ??? ?? MySQL?? ??? ??? ????? ??? ? ????.

? ??? MySQL?? ANSI SQL RANK ??? ???? ??? ??????? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!

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