合併語句生成異常，但爲什麼

Question

此合併語句引發ORA-00905：缺少關鍵字異常。可能是什麼問題？什麼與WHEN MATCHED分支？

MERGE INTO WORKERPROJECT TARGET 
USING (SELECT distinct 
       w.worker_id, 
       w.worker_type, 
       w.project_id worker_project_id, 
       p.project_id project_project_id, 
       p.dedicated_project_leader, 
       p.dedicated_lead_developer, 
       p.dedicated_lead_consultant, 
       p.dedicated_supervisor 
     from WORKER w 
     join PROJECT p on w.project_id = p.project_id 
    ) SOURCE 
    ON (TARGET.FK_worker_id=SOURCE.WORKER_ID) 
WHEN MATCHED THEN INSERT (TARGET.FK_WORKER_ID, TARGET.FK_PROJECT_ID,TARGET.IS_ACTIVE,POSITION) 
    VALUES (SOURCE.WORKER_ID,SOURCE.worker_project_id,'IS_ACTIVE',SOURCE.worker_type); 

Answer 1

根據http://www.oracle-base.com/articles/10g/merge-enhancements-10g.php

你只能做WHEN NOT MATCHED插入。