Oracle数据库常用sql语句

1、有数据就执行更新操作，没有的话就执行插入操作

MERGE INTO score_statistics A
USING (select gameid from score_statistics where gameid=82) B
ON (B.gameid = A.gameid)
WHEN MATCHED THEN   
     UPDATE SET A.SCOREAVERAGE=0.8   
WHEN NOT MATCHED THEN    
     insert (GAMEID,SCOREAVERAGE,SCORENUMBER,SCORETOTAL) values (88,0.6,11,6);

2、数据库左连接

SELECT P.PROGRAMA_ID AS programaId, P.PROGRAMA_NAME AS programaName, 
		P.PROGRAMA_HOST AS programaHost, 
		P.PROGRAMA_DIRECTOR AS programaDirector, 
		P.PROGRAMA_RECORDING_TIME AS programaRecordingTime, 
		A.PROGRAMA_ATTENTION_COUNT AS programaAttentionCount, 
		S.PROGRAMA_AVERAGE_SCORE AS programaAverageScore, 
		R.PROGRAMA_REMIND_COUNT AS programaRemindCount 
		FROM PROGRAMA_INFO P 
		LEFT JOIN PROGRAMA_ATTENTION_STATISTICS A ON P.PROGRAMA_ID = A.PROGRAMA_ID 
		LEFT JOIN PROGRAMA_SCORE_STATISTICS S ON P.PROGRAMA_ID = S.PROGRAMA_ID 
		LEFT JOIN PROGRAMA_REMIND_STATISTICS R ON P.PROGRAMA_ID = R.PROGRAMA_ID 
		WHERE P.PROGRAMA_ID = #value#