Question

我有一张包含gr_no，year_dob，family_id等的表格。我试图根据family_id对出生年份进行排名，但无法生成siblings_rank结果。

+----------+--------------+-----------+
| gr_no    | year_dob     | family_id | siblings_rank
+----------+--------------+-----------+
|     1001 | 1992         |    95     |  1
|    10234 | 1995         |    95     |  2
|    10236 | 2004         |    96     |  1
|    15568 | 2006         |    96     |  2
|     1225 | 2004         |    92     |  1
+----------+--------------+-----------+

此查询有效：

SET @prev := null;

SET @cnt := 1;

SELECT gr_no, gs_id, gf_id, year_dob, IF(@prev <> gf_id, @cnt := 1, @cnt := @cnt + 1) AS siblings_position, @prev := gf_id as previous_gf_id
FROM student_registered
ORDER BY gf_id, year_dob asc

此查询也有效：

SELECT gr_no, gs_id, gf_id, year_dob, IF(@prev <> gf_id, @cnt := 1, @cnt := @cnt + 1) AS siblings_position, @prev := gf_id as previous_gf_id
FROM student_registered
JOIN (SELECT @prev := null) p
JOIN (SELECT @cnt := 1) c
ORDER BY gf_id, year_dob asc

...............我无法使用这些查询创建视图？

或如果一个过程可以根据查询更新student_registered列'siblings_position'吗？

Answer 1

你不能在视图中使用sql变量

这是使用相关子查询

获得相同结果的另一种方法

SELECT gr_no, family_id,year_dob,
       ( select count(*) from Table1  T1
         where T1.family_id = T.family_id
         and T1.year_dob <= T.year_dob) as siblings_position
FROM Table1 T
ORDER BY family_id, year_dob asc

如何根据组和出生年份获得排名

1 个答案: