Question

我有以下查询：

select count(*)
FROM
    cumul AS t1,
    cumul AS t2
WHERE
    t1.id+1 = t2.id
and
    t2.spec_datetime-t1.spec_datetime < 0.001
and
    t1.id < 100000
and
    t1.v1-t2.v1 = 0
and
    t1.v2-t2.v2 =0;

我想删除相同的记录：

DELETE FROM cumul AS t1, cumul AS t2
WHERE
    t1.id+1 = t2.id
and
    t2.spec_datetime-t1.spec_datetime < 0.001
and
    t1.v1-t2.v1 = 0
and
    t1.v2-t2.v2 = 0;

我明白了：

错误1064（42000）：您的SQL语法有错误;检查手册对应于您的MySQL服务器版本，以便在'AS t1附近使用正确的语法，cumul AS t2 WHERE t1.id + 1 = t2.id和t2.spec_datetime-t1.spec_datetime＆lt;'在第1行

如何更正查询？

Answer 1

DELETE t1 FROM cumul AS t1, cumul AS t2  
       ^^
Just add alias before FROM

所以试试这个：

DELETE t1 FROM cumul AS t1, cumul AS t2
WHERE
    t1.id+1 = t2.id
and
    t2.spec_datetime-t1.spec_datetime < 0.001
and
    t1.v1-t2.v1 = 0
and
    t1.v2-t2.v2 = 0;

有关详细信息，请参阅MySQL :: 13.2.2. DELETE Syntax。

Answer 2

您必须指定要删除的表列表中的哪个表（即使它们在此实例中是相同的表）：

DELETE t1 FROM cumul AS t1, cumul AS t2...

http://dev.mysql.com/doc/refman/5.0/en/delete.html

mysql删除连续的行

2 个答案: