关于BETWEEN查出重复记录的问题
在MYSQL上做了这么一件事
CREATE TABLE TT
(
AA VARCHAR(5),
BB DATETIME
);
INSERT INTO TT VALUES ('AAAAA', NOW());
INSERT INTO TT VALUES ('BBBBB', NOW());
INSERT INTO TT VALUES ('CCCCC', NOW());
INSERT INTO TT VALUES ('DDDDD', NOW());
结果是
AA BB
"AAAAA","2009-09-04 10:49:01"
"BBBBB","2009-09-04 10:49:06"
"CCCCC","2009-09-04 10:49:10"
"DDDDD","2009-09-04 10:49:13"
查询语句
SELECT AA,BB FROM TT
WHERE BB BETWEEN STR_TO_DATE('20090904104906','%Y%m%d%H%i%S') AND STR_TO_DATE('20090904110015','%Y%m%d%H%i%S')
得到结果
AA BB
"BBBBB","2009-09-04 10:49:06"
"CCCCC","2009-09-04 10:49:10"
"DDDDD","2009-09-04 10:49:13"
"BBBBB","2009-09-04 10:49:06"
"CCCCC","2009-09-04 10:49:10"
"DDDDD","2009-09-04 10:49:13"
谁能帮我解释解释。。。为什么结果集会多出重复的记录?