如何在mysql中聲明變量存儲過程？

Question

我想聲明一個變量，然後爲該特定變量分配一個select查詢的值，然後我需要在insert語句中傳遞該變量。所以，我想下面的代碼，

DROP PROCEDURE IF EXISTS `pro_damagestockdao` $$ 
CREATE DEFINER=`root`@`localhost` PROCEDURE `pro_damagestockdao`(
IN damage_date date, 
IN damage_inv_no varchar(12), 
IN damage_inv_date date, 
IN damage_dist_name varchar(30), 
IN damage_contact_no varchar(15), 
IN damage_item_code varchar(30), 
IN damage_item_name varchar(30), 
IN damage_batch_no varchar(15), 
IN damage_mfr_name varchar(50), 
IN damage_expiry_date date, 
IN damage_pur_qty int(11), 
IN damage_qty int(11), 
IN damage_unit_price double(10,2), 
IN damage_unit_vat double(4,2), 
IN damage_unit_discount double(4,2), 
IN damage_sub_total double(10,2), 
IN damage_total_amount double(10,2), 
IN damage_remarks varchar(1000), 
IN functionality varchar(20), 
out flag int 
) 
BEGIN 

DECLARE selCnt int; 
DECLARE dqty int; 
SET dqty = (SELECT free FROM purchase_invoice p WHERE p.invoice_no = damage_inv_no); 

DECLARE EXIT HANDLER FOR SQLEXCEPTION ROLLBACK; 

SET flag=0; 

START TRANSACTION; 

if(functionality='save') then 

INSERT INTO damage_stocks 
(damage_stock_date,invoice_no,invoice_date,dist_name,contact_no,item_code,item_name,batch_no,qty,damaged_qty,unit_price,unit_vat,unit_discount,sub_total,total_amount,remarks) VALUES 
(damage_date,damage_inv_no,damage_inv_date,damage_dist_name,damage_contact_no,0,damage_item_name,damage_batch_no,dqty,damage_qty,damage_unit_price,damage_unit_vat,damage_unit_discount,damage_sub_total,damage_total_amount,damage_remarks); 

但它沒有。你看，我聲明的變量dqty，然後我把它傳遞給insert聲明。

Answer 1

聲明沒有問題。這是分配問題 嘗試此查詢

SELECT free into dqty FROM purchase_invoice p WHERE p.invoice_no = damage_inv_no; 

Answer 2

下面的代碼工作正常，我：

DELIMITER $$ 
USE `test`$$ 
DROP PROCEDURE IF EXISTS `pro_damagestockdao`$$ 

CREATE DEFINER=`root`@`localhost` PROCEDURE `pro_damagestockdao`(
IN damage_date DATE, 
IN damage_inv_no VARCHAR(12), 
IN damage_inv_date DATE, 
IN damage_dist_name VARCHAR(30), 
IN damage_contact_no VARCHAR(15), 
IN damage_item_code VARCHAR(30), 
IN damage_item_name VARCHAR(30), 
IN damage_batch_no VARCHAR(15), 
IN damage_mfr_name VARCHAR(50), 
IN damage_expiry_date DATE, 
IN damage_pur_qty INT(11), 
IN damage_qty INT(11), 
IN damage_unit_price DOUBLE(10,2), 
IN damage_unit_vat DOUBLE(4,2), 
IN damage_unit_discount DOUBLE(4,2), 
IN damage_sub_total DOUBLE(10,2), 
IN damage_total_amount DOUBLE(10,2), 
IN damage_remarks VARCHAR(1000), 
IN functionality VARCHAR(20), 
OUT flag INT) 
BEGIN 
DECLARE selCnt INT; 
DECLARE dqty INT; 
DECLARE EXIT HANDLER FOR SQLEXCEPTION ROLLBACK; 

SET dqty = (SELECT free FROM purchase_invoice p WHERE p.invoice_no = damage_inv_no); 
SET flag = 0; 
START TRANSACTION; 
IF(functionality = 'save') THEN 
    INSERT INTO damage_stocks (damage_stock_date, invoice_no, invoice_date, dist_name, contact_no, item_code, item_name, batch_no, qty,damaged_qty, unit_price, unit_vat, unit_discount, sub_total, total_amount, remarks) 
    VALUES (damage_date, damage_inv_no, damage_inv_date, damage_dist_name, damage_contact_no, 0, damage_item_name, damage_batch_no, dqty,damage_qty, damage_unit_price, damage_unit_vat, damage_unit_discount, damage_sub_total, damage_total_amount, damage_remarks); 

END IF; 

END$$ 

DELIMITER ; 

有了這個SP電話：

CALL `pro_damagestockdao`("2015-06-23","rx45","2015-06-20","DistName","DContactNo","DamageItemCode","damage_item_name","damage_batch_no","damage_mfr_name", "2015-07-01", 10, 5, 15.2, 7.66, 9.88, 99.00, 150.22, "No remarks", "save", @sorin); 

你什麼錯誤？ 嘗試創建存儲過程或調用它時是否出錯？