PHP:使用mysql获取数据库中的最后一行 [英] PHP: get the last row in database using mysql

问题描述

我在一个表中有三行.我正在尝试获取并显示表格的最后一行，相反，它始终显示中间行的结果.

I have three rows in a table. I'm trying to get and display the last row of my table and, instead, its always displaying the result of the middle row.

我曾尝试使用 "DESC" 或 "DESC LIMIT 1" 但仍然无法正常工作.

I have tried to used the "DESC" or "DESC LIMIT 1" but still its not working.

示例:

我的 tbldata 表中有 3 行.

I have a 3 rows in my table of tbldata.

0:5

0:10

0:15

查询:

$result = mysql_query("SELECT fldBldgName, fldTimestamp,   
MIN(fldTotalDuration)fldTotalDuration   
FROM tbldata    
WHERE  fldNetname = '".$network."'   
AND fldBldgName = '".$bldg[$i]."'    
AND  fldWeek = '".$week."'   
AND fldMonth = '".$month."'   
GROUP BY fldBldgName   
ORDER BY  fldBldgName,fldTimestamp, fldTotalDuration DESC");

我已经尝试了 ID to order 但仍然无法正常工作.我尝试了 timestamp，但仍然无法正常工作.

I already tried also the ID to order by but still its not working. I tried the timestamp, but still its not working.

那个查询的结果总是"0:10"，正确的输出应该是"0:15".

The result for that query is always the "0:10", the correct output should be "0:15".

但是如果我只有 2 行:

But then if I have 2 rows only:

0:5

0:10

结果是:0:10这是正确的

所以，我也试过在phpmyadmin中手动查询，但还是不显示最后一行.

And so, I also tried it to manually query it in phpmyadmin, but it still does not display the last row.

推荐答案

假设您有一个 id 字段并设置了 AUTO_INCREMENT.

Assuming you have an id field with AUTO_INCREMENT set.

那就试试这个

SELECT * FROM tbl ORDER BY id DESC LIMIT 1;

您对 MIN(fldTotalDuration) 和 GROUP BY 的使用完全混淆了您所追求的结果.

Your use of MIN(fldTotalDuration) and GROUP BY was totally confusing the result you were after.

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