该博客介绍了如何在SQL中处理重复记录的问题。首先，通过`SELECT DISTINCT * INTO`创建了一个没有重复记录的新表，然后删除原始表。接着，通过`SELECT * FROM`找出存在重复记录的行，并保留`tbrq`字段值最小的记录。最后，使用`DELETE`语句删除了重复记录，确保每条记录的`bz`唯一且对应的`tbrq`是最小的。
1.去除重复记录
select distinct * into jkb_1 from jkb
drop table jkb
select * into jkb from jkb_1
2.查找表中多余的重复记录
select * from jkb where bz in
(select bz from jkb group by bz having count(1)>1)
3.删除表中多余的重复记录，只留有tbrq最小的记录
select *
from jkb where bz in
(select bz from jkb group by bz having count(bz) > 1)
and tbrq not in (select min(tbrq) from jkb group by bz having count(bz)>1)
delete from jkb where bz in
(select bz from jkb group by bz having count(bz) > 1)
and tbrq not in (select min(tbrq) from jkb group by bz having count(bz)>1)
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