具有多個計數的MySQL性能

Question

在一個查詢中具有多個MySQL Count實例或爲每個計數實例分別查詢是否更快？如果是這樣，我將如何結合這兩個查詢？

$msd_call_qry = "SELECT count(event) AS MissedCalls FROM queuelogdb.queue_log WHERE (agent = '$agent_name[0]' OR agent = '$agent_name[1]')" 
       . " AND (event = 'ABANDON' OR event = 'RINGNOANSWER') AND queuename IN ('500','505') AND time BETWEEN '$lastDay' AND '$today'"; 

$ttl_call_qry = "SELECT count(event) AS TotalCalls from queuelogdb.queue_log WHERE (agent = '$agent_name[0]' OR agent = '$agent_name[1]') " 
       . "AND event = 'CONNECT' AND queuename IN ('500','505') AND time BETWEEN '$lastDay' AND '$today'"; 

Answer 1

你的表是一樣的。 WHERE條款中的大部分條件都是相同的。所以，你應該能夠使用條件彙總：

SELECT SUM(event = 'ABANDON' OR event = 'RINGNOANSWER') AS MissedCalls, 
     SUM(event = 'CONNECT') AS TotalCalls 
FROM queuelogdb.queue_log 
WHERE agent IN ('$agent_name[0]', '$agent_name[1]') AND 
     queuename IN ('500', '505') AND 
     time BETWEEN '$lastDay' AND '$today'". ";