Question

我要过滤重复项并从这些重复项中获取一条记录。（电话号码列仅重复项，其他不重复）

For eg:
    row_count   state   phone   areacode    zip
    1           a       123     989         321
    2           z       123     981         322
    3           x       123     982         323
    4           d       321     983         324
    5           a       321     984         325
    6           b       098     985         326
    7           c       098     986         327

我想要这样的O / P：

row_count   state   phone   areacode    zip
    1           a       123     989         321
    4           d       321     983         324
    6           b       098     985         326

Answer 1

使用相关子查询

select * from  table1 t1 where row_count = 
 (select min(row_count) 
 from table1 t2 
 where t1.phone=t2.phone 
 )

Answer 2

一种方法联接到子查询，该子查询过滤掉所有记录，但那些电话号码的row_count最少：

SELECT t1.*
FROM yourTable t1
INNER JOIN
(
    SELECT phone, MIN(row_count) AS min_row_count
    FROM yourTable
    GROUP BY phone
) t2
    ON t1.phone = t2.phone AND t1.row_count = t2.min_row_count;

这是使用解析功能的MySQL 8+方法：

SELECT row_count, state, phone, areacode, zip
FROM
(
    SELECT *, MIN(row_count) OVER (PARTITION BY phone) min_row_count
    FROM yourTable
) t
WHERE row_count = min_row_count;

从重复记录中筛选出MYSQL中的单个记录

2 个答案: