如何从两个查询中构建一个查询？

Question

我有两个查询，当我将它们粘贴到 phpmyadmin 的 sql 控制台时表现良好：

第一次查询：

SET @count=0,@msisdn=00385913586990,@delivered=0;

第二次查询：

SELECT tmp.msisdn,max(count) FROM (
        SELECT
        sent_messages.msisdn,
        @count := if(delivered = 0 and sent_messages.msisdn = @msisdn, @count+1, 0) as count,
        @msisdn := 00385913586990,
        @delivered := delivered
        FROM  `sent_messages`
        WHERE  `msisdn` LIKE  '00385913586990'
        AND  `type` =  'PAID' ) as tmp
        group by tmp.msisdn
        having max(count) >= 14

当我尝试在我的 php 代码中执行这些查询时，我得到了空白结果。

以下是我尝试将它们绑定在一起的方法：

SELECT tmp.msisdn,max(count) FROM (
            SELECT
            sent_messages.msisdn,@count := 0,@msisdn=00385913586990,@delivered=0,
            @count := if(delivered = 0 and sent_messages.msisdn = @msisdn, @count+1, 0) as count,
            @msisdn := 00385913586990,
            @delivered := delivered
            FROM  `sent_messages`
            WHERE  `msisdn` LIKE  '00385913586990'
            AND  `type` =  'PAID' ) as tmp
            group by tmp.msisdn
            having max(count) >= 14

但这行不通。

Answer 1

初始化您简单交叉连接的子查询中的变量。这样他们就被初始化了一次。当您在 SELECT 子句中执行此操作时，每次读取一行时它们都会退回。

SELECT tmp.msisdn,max(count) FROM (
        SELECT
        sent_messages.msisdn,
        @count := if(delivered = 0 and sent_messages.msisdn = @msisdn, @count+1, 0) as count,
        @msisdn := 00385913586990,
        @delivered := delivered
        FROM  `sent_messages`
        , (SELECT @count := 0, @msisdn := '00385913586990', @delivered := 0) var_init_subquery_alias
        WHERE  `msisdn` LIKE  '00385913586990'
        AND  `type` =  'PAID' ) as tmp
        group by tmp.msisdn
        having max(count) >= 14

如何从两个查询中构建一个查询？

How to build one query out of two?

mysql