Warning: file_get_contents(/data/phpspider/zhask/data//catemap/1/php/247.json): failed to open stream: No such file or directory in /data/phpspider/zhask/libs/function.php on line 167

Warning: Invalid argument supplied for foreach() in /data/phpspider/zhask/libs/tag.function.php on line 1116

Notice: Undefined index: in /data/phpspider/zhask/libs/function.php on line 180

Warning: array_chunk() expects parameter 1 to be array, null given in /data/phpspider/zhask/libs/function.php on line 181

Warning: file_get_contents(/data/phpspider/zhask/data//catemap/8/mysql/64.json): failed to open stream: No such file or directory in /data/phpspider/zhask/libs/function.php on line 167

Warning: Invalid argument supplied for foreach() in /data/phpspider/zhask/libs/tag.function.php on line 1116

Notice: Undefined index: in /data/phpspider/zhask/libs/function.php on line 180

Warning: array_chunk() expects parameter 1 to be array, null given in /data/phpspider/zhask/libs/function.php on line 181
Php 日期为最大值时筛选结果_Php_Mysql_Sql - Fatal编程技术网

Php 日期为最大值时筛选结果

Php 日期为最大值时筛选结果,php,mysql,sql,Php,Mysql,Sql,有人能告诉我我做错了什么吗 我试图选择一个满是结果的表,有些是重复的,但时间戳不同,所以我想按最新日期过滤掉 我正在使用下面的sql查询,但它总是抛出错误 $sql = "(SELECT * FROM measrate WHERE TRANS_TIME = (SELECT MAX(TRANS_TIME) FROM measrate)"; 忘记最后一个括号首先,不需要初始括号: SELECT m.* FROM measrate m WHERE TRANS_TIME = (SELECT M

有人能告诉我我做错了什么吗

我试图选择一个满是结果的表,有些是重复的,但时间戳不同,所以我想按最新日期过滤掉

我正在使用下面的sql查询,但它总是抛出错误

$sql = "(SELECT  *
FROM    measrate
WHERE TRANS_TIME = (SELECT MAX(TRANS_TIME) FROM measrate)";

忘记最后一个括号首先,不需要初始括号:

SELECT m.*
FROM measrate m
WHERE TRANS_TIME = (SELECT MAX(TRANS_TIME) FROM measrate m2);
其次,如果只需要某个组的最大时间(例如基于列结果),请将其修改为相关子查询:

SELECT m.*
FROM measrate m
WHERE TRANS_TIME = (SELECT MAX(TRANS_TIME) FROM measrate m2 WHERE m2.result= m.result);

子select本身运行正常吗?您会遇到什么错误?请尝试$sql=select*FROM measrate,其中TRANS_TIME=select MAXTRANS_TIME FROM measrate;丢失的added@Manwal谢谢,它成功了,但它似乎给了我全套的最长日期,所以我从大约1000个结果中得到了一个结果,我只需要过滤掉重复的结果,我做错了吗?
SELECT m.*
FROM measrate m
WHERE TRANS_TIME = (SELECT MAX(TRANS_TIME) FROM measrate m2 WHERE m2.result= m.result);