在MySQL栏中找到最大值

Question

seems like this question has been answered alot, but I can't get it to work!

Have a 'Month' column in DB table, that reaches 313 as max entry.

Am trying to assign this max amount to a PHP value which is working but keeps returning $maxmonth as 99?

Current Coding:

$result=mysqli_query($con,"SELECT MAX(Month) AS max from $ulliabforecast");

            {while ( $row = $result->fetch_assoc() )
            $maxmonth=$row['max'];}

Appreciate any help.

Answer 1

似乎您的Month是VARCHAR ，您需要执行CAST使其正常工作。

SELECT MAX(CAST(Month AS SIGNED)) AS max1 from $ulliabforecast

Answer 2

Try

SELECT `month` FROM $ulliabforecast ORDER BY `month` DESC LIMIT 0,1

As your sql query, this should select the largest month column from your database.

Answer 3

You might be using Month column as a VARCHAR type, change it to INT and your problem will be solved.

Have a good day.

Answer 4

You can be using month as VARCHAR . Please Check.

And if true you can convert it to UNSIGNED and then get Max out of it

Please try below SQL Statement

SELECT MAX(CAST(`month` AS UNSIGNED)) AS max FROM $ulliabforecast 

Note

As described in Cast Functions and Operators :

The type for the result can be one of the following values:

• BINARY[(N)]
• CHAR[(N)]
• DATE
• DATETIME
• DECIMAL[(M[,D])]
• SIGNED [INTEGER]
• TIME
• UNSIGNED [INTEGER]