How to do IF NOT EXISTS in SQLite

http://stackoverflow.com/questions/531035/how-to-do-if-not-exists-in-sqlite

How about this?

INSERT OR IGNORE INTO EVENTTYPE (EventTypeName) VALUES 'ANI Received'

(Untested as I don't have SQLite... however this link is quite descriptive.)

Additionally, this should also work:

INSERT INTO EVENTTYPE (EventTypeName)
SELECT 'ANI Received'
WHERE NOT EXISTS (SELECT 1 FROM EVENTTYPE WHERE EventTypeName = 'ANI Received');

需要注意的是，这里的Insert Into后面是没有Values；

Values是通过后面的Select来实现的

 

 

参考这个

internal static string InsertIdxFile =

@"Insert Into SensorData(ID,ProjectID,SensorIdx,IdxFile,StartTimestamp,EndTimestamp) 
SELECT '{0}','{1}','{2}','{3}','{4}','{5}'
WHERE NOT EXISTS (SELECT 1 FROM SensorData WHERE ID = '{0}')";

 

作者:Chuck Lu    GitHub