如何通过其用户名相关的主user_name获取所有值

Question

我从这个数据库中获取值。我需要按sim_id排序的总request_amount，其中username由user_name和parents彼此相关。例如Alam=>Shimul，Shimul=>Shihab，Shihab=>Khaled等等......然后当我只搜索user_name='Alam'时所有user_name的主要父母时，那么输出将跟随....

数据表user_request

user_name   sim_id  request_amount  request_date  parents
Alam        1        98             2014-01-11    Admin
Shimul      2       100             2014-01-11    Alam
Shihab      3        50             2014-01-11    Shimul
Khaled      2        20             2014-01-11    Shihab
Sumon       3       100             2014-01-11    Shihab

输出

user_name    sim_id1        sim_id2         sim_id3        total
Alam          98              0               0              98
Shimul         0            100               0             100
Shihab         0              0              50             200
Khaled         0             20               0              20
Sumon          0              0             100             100

请有人帮我解决问题......

Answer 1

像这样的东西，使用SUM但在SUM中有一个IF： -

SELECT user_name, 
        SUM(IF(sim_id = 1, request_amount, 0)) AS sim_id1,
        SUM(IF(sim_id = 2, request_amount, 0)) AS sim_id2,
        SUM(IF(sim_id = 3, request_amount, 0)) AS sim_id3,
        SUM(sim_id) AS total
FROM user_request
GROUP BY user_name