在a表上建立触发器,当往a表中写入数据时,触动插入触发器,把数据写到b表中,并且b表中不存在该条记录
a表的结构d_code(主键),d_name,b表的结构d_code(主键),d_name该表中已经存在一部分数据,麻烦给位该触发器怎么写,非常感谢
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- SQL code
/* Formatted on 2011/11/22 10:54 (Formatter Plus v4.8.8) */ CREATE OR REPLACE TRIGGER tri_a_i BEFORE INSERT ON a FOR EACH ROW DECLARE v_count NUMBER; BEGIN SELECT COUNT (d_code) INTO v_count FROM b WHERE d_code = :NEW.d_code; IF v_count = 0 THEN INSERT INTO b (d_code, d_name ) VALUES (:NEW.d_code, :NEW.d_name ); END IF; EXCEPTION WHEN OTHERS THEN NULL; END;