生成创建触发器所需的SQL（Oracle）

Posted 2021-02-27

Generate the SQL necessary to create triggers that use the sequences listed above.
NOTE: This particular script assumes that the tables all start with ‘tbl’.
It may need to be modified to work with different naming conventions.

SELECT 'CREATE OR REPLACE TRIGGER trg' || substr (TABLE_NAME,4,LENGTH(TABLE_NAME)-3) || '
before insert on tbl' || substr (TABLE_NAME,4,LENGTH(TABLE_NAME)-3) || '
for each row
declare
	begin
		 if (:new.' || substr (TABLE_NAME,4,LENGTH(TABLE_NAME)-3) || 'id =0) or (:new.' || substr (TABLE_NAME,4,LENGTH(TABLE_NAME)-3) || 'id is null) then
		 begin
			select tbl' || substr (TABLE_NAME,4,LENGTH(TABLE_NAME)-3) || '_seq.nextval
			into
			:new.' || substr (TABLE_NAME,4,LENGTH(TABLE_NAME)-3) || 'id from dual;
		end;
		end if;
	end;
/ '
FROM user_tables