Question

在手机系统方案中，我有2张桌子。

table1由以下内容组成：customer_id，call_duration，calldate，skip_billing。
table2由以下内容组成：customer_id，bonus_seconds。

table1存储所有客户的所有呼叫，table2存储bonus_seconds，表示定义客户允许的免费通话时间（即：对于客户1，FIRST 40累积秒数是免费的）。

我必须根据下面解释的条件编写一个更新table1的查询：在table2中免费定义的调用中设置skip_billing。

所以我首先需要按customer_id进行分组，然后迭代调用，在call_duration上递增累积变量（cumsec）并相应地设置skip_billing。

table1的例子是：

|sqlid |customer_id |billsec | skipbill|
|0     |1           |12      | 1       |<--need to set 1 due to cume=12 for customer_id=1
|1     |1           |10      | 1       |<--need to set 1 due to cume=22 for customer_id=1
|2     |1           |15      | 1       |<--need to set 1 due to cume=37 for customer_id=1
|3     |1           |8       | 0       |<--nop(no operation) due to cume=45
|4     |2           |12      | 1       |<--need to set 1 due to cume=12 for customer_id=2
|5     |3           |12      | 1       |<--need to set 1 due to cume=12 for customer_id=3
|6     |2           |12      | 0       |<--nop due to cume=24 for customer_id=2
|7     |1           |12      | 0       |<--nop due to cume=49 for customer_id=1
|8     |3           |15      | 0       |<--nop due to cumsec=27 for customer_id=3

|customer_id |bonus_seconds|
|1           |40           |
|2           |20           |
|3           |15           |

我尝试了这样的查询（感谢Gordon Linoff），它返回了正确的行集：

    SELECT t.cume, t.calldate, t.customer_id FROM (SELECT t.*, (@cume := @cume + billsec) AS cume FROM table1 t CROSS JOIN (SELECT @cume := 0) vars ORDER BY calldate) t, table2 sct WHERE t.cume <= sct.bonus_seconds AND t.customer_id=sct.customer_id ;

但是，当我尝试使用UPDATE时，如下面的命令，它不起作用，因为不匹配任何东西。

    UPDATE table1 SET skipbill=1 WHERE sqlid=(SELECT t.sqlid FROM (SELECT t.*, (@cume := @cume + billsec) AS cume FROM table1 t CROSS JOIN (SELECT @cume := 0) vars ORDER BY calldate) t, table2 sct WHERE t.cume <= sct.bonus_seconds AND t.customer_id=sct.customer_id ) ;

如何使用该查询或其他更好的方式编写更新任务？

提前谢谢

Answer 1

在我看来，你要为客户1（例如）收费3秒，这应该是他们奖金的一部分，但无论如何......

 SELECT x.*
      , SUM(y.billsec) cumu
      , IF(SUM(y.billsec)<=z.bonus_seconds,1,0) n 
   FROM my_table x 
   JOIN my_table y 
     ON y.customer_id = x.customer_id 
    AND y.sqlid <= x.sqlid 
   LEFT 
   JOIN bonus z 
     ON z.customer_id = x.customer_id 
  GROUP 
     BY x.customer_id
      , x.sqlid 
  ORDER 
     BY sqlid;

Answer 2

UPDATE table1 
SET skipbill = 1 
WHERE sqlid IN (
    SELECT DISTINCT t.sqlid 
    FROM (
        SELECT t.*, (@cume := @cume + billsec) AS cume 
        FROM table1 t 
        CROSS JOIN (SELECT @cume := 0) vars 
        ORDER BY calldate
    ) t, table2 sct 
    WHERE t.cume <= sct.bonus_seconds 
          AND t.customer_id = sct.customer_id
);

SQL：复杂选择的UPDATE

2 个答案: