[英]Incorrect result for date comparison (to a timestamp column) in mysql
I've been having some 'strange' results while comparing dates. 在比较日期时,我一直有一些“奇怪”的结果。
table1
has two rows with TIMESTAMPS values 2009-08-26 23:39:56
and 2009-08-27 00:01:42
table1
有两行的TIMESTAMPS值分别为2009-08-26 23:39:56
和2009-08-27 00:01:42
2009-08-26 23:39:56
When I make this query: 当我进行此查询时:
select * from table1 c
INNER JOIN table2 r ON r.table1_id = c.id
WHERE DATE(c.authorization_date) = '2009-08-26'
it returns both rows (when it only should have returned one). 它返回两行(当它仅应返回一个时)。
For added weirdness the rows in the returned resultSet have tha same value: 2009-08-26 23:39:56
为了增加怪异,返回的resultSet中的行具有相同的值: 2009-08-26 23:39:56
But If I make this query: 但是,如果我进行以下查询:
SELECT DATE(authorization_date) FROM table1
It correctly returns two rows with values 2009-08-26
and 2009-08-27
它正确返回两行,其值分别为2009-08-26
和2009-08-27
So, here comes my questions. 所以,这是我的问题。 How could I make the comparison so the correct result is returned, what am i doing wrong? 我如何进行比较,以便返回正确的结果,我在做什么错? Could be related to the inner join? 可能与内部联接有关吗?
I suspected: 我怀疑:
some timezone discrepency, but you seem to have accounted for that 某些时区差异,但您似乎已经对此做出了解释
some other data that is confusing the problem... is there something else that could be interfering? 其他一些令人困惑的数据...还有其他可能干扰的东西吗?
Wish I could recreate this and help. 希望我能重做并提供帮助。 Here's my setup code. 这是我的设置代码。 What am I missing? 我想念什么?
mysql> create table table1 (id integer primary key auto_increment, authorization_date TIMESTAMP);
mysql> insert into table1 values (1, '2009-08-26 23:39:56');
mysql> insert into table1 values (2, '2009-08-27 00:01:42');
mysql> create table table2 (table1_id integer);
mysql> insert into table2 values (1);
mysql> insert into table2 values (2);
mysql> SELECT DATE(authorization_date) FROM c;
+--------------------------+
| DATE(authorization_date) |
+--------------------------+
| 2009-08-26 |
| 2009-08-27 |
+--------------------------+
mysql> select * from table1 c INNER JOIN table2 r ON r.table1_id = c.id WHERE DATE(c.authorization_date) = '2009-08-26';
+----+---------------------+-----------+
| id | authorization_date | table1_id |
+----+---------------------+-----------+
| 1 | 2009-08-26 23:39:56 | 1 |
+----+---------------------+-----------+
1 row in set (0.00 sec)
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.