当我从java代码插入记录时，mysql触发器不起作用

Question

DELIMITER //

DROP TRIGGER insert_orderinward_trig; //

CREATE TRIGGER insert_orderinward_trig AFTER INSERT ON tblm_tlmngorderinward FOR EACH ROW
BEGIN

    call temp_proc(NEW.itemcode);

END; //

我把程序写成

DELIMITER //

DROP PROCEDURE temp_proc; //

CREATE PROCEDURE temp_proc(IN code VARCHAR(80))

BEGIN
    DECLARE inwardstock,issuestock,updatestock DECIMAL(15,0) DEFAULT 0;

    SET inwardstock = (SELECT SUM(stock) FROM tblm_tlmngorderinward WHERE itemcode = code);
    IF(@inwardstock > 0) THEN
        SET updatestock =inwardstock;   
    END IF;


    SET issuestock = (SELECT SUM(stock) FROM tblt_tlmngissueitem WHERE itemcode = code);

    IF(@issuestock > 0) THEN
        SET updatestock = @updatestock-@issuestock ;    
    END IF;

    UPDATE tblm_tlmngitem SET stock=updatestock  WHERE itemcode=code;

END; //

DELIMITER ;

当我手动插入记录时，我的插入触发器工作正常。但是当我在java中使用preparestatement插入记录时它不能工作。

Answer 1

乍一看，您似乎有两个变量 inwardstock/@inwardstock 和 issuestock/@issuestock 看起来是错误的：

DECLARE inwardstock,issuestock,updatestock DECIMAL(15,0) DEFAULT 0;

IF(@inwardstock > 0) THEN <--- @inwardstock or inwardstock !!

...

IF(@issuestock > 0) THEN <--- @issuestock or issuestock !!

我的另一个建议是完全删除触发器并调用存储过程：

delimiter #

create procedure insert_tblm_tlmngorderinward
(
in p_itemcode varchar(80) -- p_ is for param
)
begin

-- v_ is for variable 

declare v_inwardstock, v_issuestock, v_updatestock decimal(15,0) default 0;

    -- do this in stored proc

    insert into tblm_tlmngorderinward (itemcode) values (p_itemcode);

    -- now do all the trigger stuff

    select sum(stock) into v_inwardstock from tblm_tlmngorderinward where itemcode = p_itemcode;
    select sum(stock) into v_issuestock from tblt_tlmngissueitem where itemcode = p_itemcode;

    if(v_inwardstock > 0) then
        set v_updatestock = v_inwardstock;      
    end if;

    if(v_issuestock > 0) then
        set v_updatestock = v_updatestock - v_issuestock;       
    end if;

    update tblm_tlmngitem set stock = v_updatestock where itemcode = p_itemcode;

end#

delimiter ;

call insert_tblm_tlmngorderinward('why_use_a_trigger');

希望这会有所帮助:)