计数count- PHP MYSQL的

Question

我的表如下：

guid version 

A1 lol 
A2 roflmao 
A1 lol 
A1 lol 
A2 lol 
A3 roflmao 
A3 roflmao 
A3 roflmao 
A3 roflmao 
A3 roflmao 
A3 roflmao 
A4 roflmao 
A4 roflmao 
A5 lol 
A5 lol 

我想指望再次数低于3次（每GUID）总roflmao出现。

到目前为止，我下面的，但它不输出任何东西：

$sql="select guid,version, count(*) as `count` 
from mytable WHERE version = 'roflmao' group by guid having `count` < 3'"; 

if ($result=mysqli_query($con,$sql)) 
{ 

// Return the number of rows in result set 

$rowcount=mysqli_num_rows($result); 
printf($rowcount); 

// Free result set 

mysqli_free_result($result); 
} 

Answer 1

试试这个：

SELECT COUNT(*) FROM (
    SELECT guid 
    FROM YourTable 
    WHERE version = 'roflmao' 
    GROUP BY guid 
    HAVING COUNT(*) <3) t 

这首先选择所有的GUID有“roflmao”出现少他们3次，然后对它们进行计数。