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  • mysql之group_concat函数详解

    函数语法:

    group_concat( [DISTINCT] 要连接的字段 [Order BY 排序字段 ASC/DESC] [Separator '分隔符'] )

    下面举例说明:

    select * from goods;

    +------+------+
    | id| price|
    +------+------+
    |1 | 10|
    |1 | 20|
    |1 | 20|
    |2 | 20|
    |3 | 200 |
    |3 | 500 |
    +------+------+
    6 rows in set (0.00 sec)

    以id分组,把price字段的值在同一行打印出来,逗号分隔(默认)

    select id, group_concat(price) from goods group by id;

    +------+--------------------+
    | id| group_concat(price) |
    +------+--------------------+
    |1 | 10,20,20|
    |2 | 20 |
    |3 | 200,500|
    +------+--------------------+
    3 rows in set (0.00 sec)

    以id分组,把price字段的值在一行打印出来,分号分隔

    select id,group_concat(price separator ';') from goods group by id;
    +------+----------------------------------+
    | id| group_concat(price separator ';') |
    +------+----------------------------------+
    |1 | 10;20;20 |
    |2 | 20|
    |3 | 200;500 |
    +------+----------------------------------+
    3 rows in set (0.00 sec)

    以id分组,把去除重复冗余的price字段的值打印在一行,逗号分隔
    select id,group_concat(distinct price) from goods group by id;

    +------+-----------------------------+
    | id| group_concat(distinct price) |
    +------+-----------------------------+
    |1 | 10,20|
    |2 | 20 |
    |3 | 200,500 |
    +------+-----------------------------+
    3 rows in set (0.00 sec)

    以id分组,把price字段的值打印在一行,逗号分隔,按照price倒序排列
    select id,group_concat(price order by price desc) from goods group by id;

    +------+---------------------------------------+
    | id| group_concat(price order by price desc) |
    +------+---------------------------------------+
    |1 | 20,20,10 |
    |2 | 20|
    |3 | 500,200|
    +------+---------------------------------------+
    3 rows in set (0.00 sec)

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  • 原文地址:https://www.cnblogs.com/nyist-xsk/p/7267092.html
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