mysqlsql数据库
需求：数据库有：列1----列2----
127.0.0.1-----123-----
127.0.0.1-----123-----
127.0.0.1-----123-----
124.254.42.38----541---
去除重复后结果
127.0.0.1---123
124.254.42.38----541
然后如何获得个数。
自己想了一下写出来后有错
select
( select
DISTINCT 列1,列2
FROM
table
),count(*)
FROM
table
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