假设你要查询的表名为table,其中有field1,field2,field3,三个字段,结果查出两条数据,这两条数据分别是“field1=1,field2=2,field3=3”和“field1=0,field2=2,field3=3”,现在需要将这两条数据拼成一条结果,结果显示为“field1=(0,1),field2=2,field3=3”,写出mysql语句,并打印两次的结果
时间: 2024-02-03 18:03:17 浏览: 51
MybatisPlus中@TableField注解的使用详解
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以下是查询语句:
```
SELECT CONCAT('field1=(',
GROUP_CONCAT(DISTINCT field1 ORDER BY field1 ASC SEPARATOR ','),
'), field2=', field2, ', field3=', field3) AS combined_fields
FROM table
WHERE (field1 = 0 OR field1 = 1) AND field2 = 2 AND field3 = 3
GROUP BY field2, field3
HAVING COUNT(DISTINCT field1) = 2
```
该语句会返回一个包含一个字段的结果集,其中这个字段的值是两条数据中只有一个字段值不同的字段值拼接而成的字符串。使用`GROUP BY`和`HAVING`子句可以筛选出符合条件的记录,使用`GROUP_CONCAT`函数可以将同一字段的多个值拼接成一个字符串,使用`DISTINCT`关键字可以去重。
为了打印两次结果,你可以在查询语句前后各使用一条`SELECT`语句,例如:
```
SELECT 'First Result:' AS label;
SELECT CONCAT('field1=(',
GROUP_CONCAT(DISTINCT field1 ORDER BY field1 ASC SEPARATOR ','),
'), field2=', field2, ', field3=', field3) AS combined_fields
FROM table
WHERE (field1 = 0 OR field1 = 1) AND field2 = 2 AND field3 = 3
GROUP BY field2, field3
HAVING COUNT(DISTINCT field1) = 2;
SELECT 'Second Result:' AS label;
SELECT CONCAT('field1=(',
GROUP_CONCAT(DISTINCT field1 ORDER BY field1 ASC SEPARATOR ','),
'), field2=', field2, ', field3=', field3) AS combined_fields
FROM table
WHERE (field1 = 0 OR field1 = 1) AND field2 = 2 AND field3 = 3
GROUP BY field2, field3
HAVING COUNT(DISTINCT field1) = 2;
```
该语句会先打印`First Result:`,然后输出第一次查询的结果,再打印`Second Result:`,最后输出第二次查询的结果。
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