SQL查询 —— 去除多个字段相同的记录，只保留一个

背景：去重，去除多个字段相同的记录，保留一个

场景一：去除表中所有重复数据，均只保留一个

delete from tbl_dept where dept_id not in (
    select id from (
        select min(dept_id) as id
        from tbl_dept 
        group by dept_name,rm_flag
    ) as temp
)

场景二：只去除表中市声部的重复数据，且只保留一个

delete from tbl_dept where dept_id not in (
    select id from (
        select min(dept_id) as id
        from tbl_dept 
        group by dept_name,rm_flag
    ) as temp
) and dept_name like '%市声部%'