达梦for的使用

BEGIN
    FOR item IN (
        select * from DB_NAME.TB_SOURCE where DEL_FLAG = 1
    ) LOOP
    
    update DB_NAME.TARGET
    set UNIT_CODE = item.UNIT_CODE,UNIT_NAME = item.UNIT_NAME
    where YEAR = item.YEAR and QUARTER = item.QUARTER and DEL_FLAG = 1;
    
    END LOOP;
END