从MYSQL查询中获取计数

我是MYSQL的新手，但我正在尝试从我已有的MYSQL选择中获取计数。
基本上，我想数一数项目的数量，然后根据它们的位置对它们进行分组。locationID是，然后显示locations.Name

这是我的（有点乱）。这将获取5000MB以上的驱动器并显示它们

Select DISTINCT 
  'C'
  , computers.computerid
  , computers.Name as ComputerName
  , Convert(CONCAT(clients.name,' ',locations.name) Using utf8) As Location
  , drives.`Size` as TestValue,0 
FROM ((drives 
LEFT JOIN Computers ON Computers.ComputerID=drives.ComputerID) 
LEFT JOIN Locations ON Locations.LocationID=Computers.Locationid)
LEFT JOIN Clients ON Clients.ClientID=Computers.clientid 
JOIN AgentComputerData on Computers.ComputerID=AgentComputerData.ComputerID 
WHERE drives.`Size` > 5000 AND  (1)  
AND Computers.ComputerID NOT IN 
  (Select ComputerID from AgentIgnore Where AgentID=0);

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提前感谢您能给我的任何帮助。

试试这个。我替换了lefts win inners，因为如果在任何表中缺少关系，则结果毫无意义。此外，我还建议在脚本端执行任何字符集转换（如果这是一个选项），并且如果您只需要一种编码，请按照这种方式对表进行编码

SELECT COUNT(*) AS NumDrives
     , CONCAT(clients.name,' ',locations.name) As Location 
  FROM drives 
 INNER  
  JOIN Computers 
    ON Computers.ComputerID=drives.ComputerID 
   AND drives.`Size` > 5000
 INNER 
  JOIN AgentComputerData on Computers.ComputerID=AgentComputerData.ComputerID     
 INNER 
  JOIN Locations 
    ON Locations.LocationID=Computers.Locationid
 INNER  
  JOIN Clients 
    ON Clients.ClientID=Computers.clientid 
 WHERE Computers.ComputerID 
   NOT 
    IN (Select ComputerID from AgentIgnore Where AgentID=0) 
 GROUP
    BY CONCAT(clients.name,' ',locations.name)

我尽可能地坚持你的描述。希望这是你需要的

Select 
  count(*) as ItemCount
  ,Locations.Name
FROM drives 
LEFT JOIN Computers ON Computers.ComputerID = drives.ComputerID
LEFT JOIN Locations ON Locations.LocationID = Computers.Locationid
LEFT JOIN Clients ON Clients.ClientID = Computers.clientid 
JOIN AgentComputerData on Computers.ComputerID = AgentComputerData.ComputerID 
WHERE drives.`Size` > 5000
AND Computers.ComputerID NOT IN 
  (Select ComputerID from AgentIgnore Where AgentID=0);
GROUP BY Locations.LocationID