PHP获取查询数据中最早的时间和最晚时间怎么写这样不知对不对
PHP获取查询数据中最早的时间和最晚时间怎么写？？这样不知对不对
如下貌似运行正常啊，但是感觉并不是这样的写法吧
$EarlyTime=mysql_result(mysql_query("select min(Time) from user where General=1 and UserID='".$row['DatID']."'",$conn),0);$LatestTime=mysql_result(mysql_query("select max(Time) from user where General=1 and UserID='".$row['DatID']."'",$conn),0);而且我感觉这样的执行效率太慢了。。。。索引了已经 还这样慢 受不鸟
请大神给个标准的获取数据库中最早时间和最后时间的方法吧
感激不尽！坐等高手！十分感谢！
回复讨论(解决方案)
在 Time、General、UserID 上都有索引吗？
两句应该合在一起写
list($EarlyTime, $LatestTime) = mysql_fetch_row(mysql_query("select min(Time), max(Time) from user where General=1 and UserID='".$row['DatID']."'"));
无以言表啊！楼上你收下我的掌声吧！
太感谢了！一下子优化了近一半！
膜拜啊。。大神！~
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