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法学如何获取触发器的元数据？
可在 INFORMATION_SCHEMA 数据库中操作。以下语句将显示触发器的元数据 −
mysql> Select trigger_schema, trigger_name, action_statement -> from information_schema.triggers\G *************************** 1. row *************************** trigger_schema: query trigger_name: trigger_before_delete_sample action_statement: BEGIN SET @count = if (@count IS NULL, 1, (@count+1)); INSERT INTO sample_rowaffected values (@count); END *************************** 2. row *************************** trigger_schema: query trigger_name: before_inser_studentage action_statement: IF NEW.age < 0 THEN SET NEW.age = 0; END IF *************************** 3. row *************************** trigger_schema: sys trigger_name: sys_config_insert_set_user action_statement: BEGIN IF @sys.ignore_sys_config_triggers != true AND NEW.set_by IS NULL THEN SET NEW.set_by = USER(); END IF; END *************************** 5. row *************************** trigger_schema: sys trigger_name: sys_config_update_set_user action_statement: BEGIN IF @sys.ignore_sys_config_triggers != true AND NEW.set_by IS NULL THEN SET NEW.set_by = USER(); END IF; END 4 rows in set (0.03 sec)
更新日期：2020-6-22
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