oracle分組取每組第一條數據

oracle分組后取每組第一條數據

 

‘數據格式

 

 

分組取第一條的效果

 

 

[sql]
SELECT *        
   FROM (SELECT ROW_NUMBER() OVER(PARTITION BY x ORDER BY y DESC) rn,        
         test1.*        
         FROM test1)        
  WHERE rn = 1  ;