どのように私はこの3つのフィールドをmysqlで数えることができますか？

Question

CASE  
WHEN EPro02.StartReportID = 101 AND EventProvider02.StartVoltage = 0 THEN 'Power Supply Disconnected' 

WHEN EventProvider02.StartSatelliteCount < 9 OR EventProvider02.StartGSMSignalLevel < 20 OR EventProvider02.StartGSMStatus != 9 THEN 'Network Outage' 

WHEN EventProvider02.StartReportID = 13 THEN 'GSM Jamming' 

END AS Reason 

Answer 1

は、あなたがより明確にあなたの質問をフレームもらえcount()とGROUP BY

SELECT 
CASE  
WHEN EPro02.StartReportID = 101 AND EventProvider02.StartVoltage = 0 THEN 'Power Supply Disconnected' 
WHEN EventProvider02.StartSatelliteCount < 9 OR EventProvider02.StartGSMSignalLevel < 20 OR EventProvider02.StartGSMStatus != 9 THEN 'Network Outage' 
WHEN EventProvider02.StartReportID = 13 THEN 'GSM Jamming' 
END AS Reason, 
count(CASE  
WHEN EPro02.StartReportID = 101 AND EventProvider02.StartVoltage = 0 THEN 'Power Supply Disconnected' 
WHEN EventProvider02.StartSatelliteCount < 9 OR EventProvider02.StartGSMSignalLevel < 20 OR EventProvider02.StartGSMStatus != 9 THEN 'Network Outage' 
WHEN EventProvider02.StartReportID = 13 THEN 'GSM Jamming' 
END) as Reason_count 
FROM your_table_join_here 
GROUP BY CASE  
WHEN EPro02.StartReportID = 101 AND EventProvider02.StartVoltage = 0 THEN 'Power Supply Disconnected' 
WHEN EventProvider02.StartSatelliteCount < 9 OR EventProvider02.StartGSMSignalLevel < 20 OR EventProvider02.StartGSMStatus != 9 THEN 'Network Outage' 
WHEN EventProvider02.StartReportID = 13 THEN 'GSM Jamming' 
END