如何与内部联接联合

Question

我有三个单独的表，bs_products、td_products 和 fv_products。

    SELECT 
bso.order_id, bso.order_num, bso.Salesman, bso.salesman_name, bso.date, bso.status,

bsp.product_id, bsp.product_branch, bsp.product_name, bsp.description, bsp.vatable, bsp.critical_stock,
bsp.quantity, bsp.sell_price, bsp.category_id, bsp.expiry_date, bsp.date, bsp.isEmpty, bsp.empties,

bss.sws_id, bss.sws_proname, bss.sws_isEmpty, bss.sws_category, bss.sws_unitprice, bss.sws_prodesc,
bss.sws_proexp, bss.sws_vat, bss.sws_number, bss.date, bss.sws_salesman, bss.sws_route, bss.sws_smname,
bss.sws_driver, bss.sws_plate, bss.sws_vehicle, bss.sws_load, bss.sws_productid, bss.sws_quantity
FROM bs_orders as bso INNER JOIN bs_products as bsp
INNER JOIN bs_sws as bss WHERE status = 'Completed' 
AND bso.date = '11/30/2016' 
AND bso.order_num = bss.sws_number 
AND bss.sws_productid = bsp.product_id 

UNION

SELECT 

tdo.order_id, tdo.order_num, tdo.Salesman, tdo.salesman_name, tdo.date, tdo.status,

tdp.product_id, tdp.product_branch, tdp.product_name, tdp.description, tdp.vatable, tdp.critical_stock,
tdp.quantity, tdp.sell_price, tdp.category_id, tdp.expiry_date, tdp.date, tdp.isEmpty, tdp.empties,

tds.sws_id, tds.sws_proname, tds.sws_isEmpty, tds.sws_category, tds.sws_unitprice, tds.sws_prodesc,
tds.sws_proexp, tds.sws_vat, tds.sws_number, tds.date, tds.sws_salesman, tds.sws_route, tds.sws_smname,
tds.sws_driver, tds.sws_plate, tds.sws_vehicle, tds.sws_load, tds.sws_productid, tds.sws_quantity

FROM td_orders as tdo INNER JOIN td_products as tdp
INNER JOIN td_sws as tds WHERE status = 'Completed' 
AND tdo.date = '11/30/2016' 
AND tdo.order_num = tds.sws_number 
AND tds.sws_productid = tdp.product_id

UNION

SELECT 

fvo.order_id, fvo.order_num, fvo.Salesman, fvo.salesman_name, fvo.date, fvo.status,

fvp.product_id, fvp.product_branch, fvp.product_name, fvp.description, fvp.vatable, fvp.critical_stock,
fvp.quantity, fvp.sell_price, fvp.category_id, fvp.expiry_date, fvp.date, fvp.isEmpty, fvp.empties,

fvs.sws_id, fvs.sws_proname, fvs.sws_isEmpty, fvs.sws_category, fvs.sws_unitprice, fvs.sws_prodesc,
fvs.sws_proexp, fvs.sws_vat, fvs.sws_number, fvs.date, fvs.sws_salesman, fvs.sws_route, fvs.sws_smname,
fvs.sws_driver, fvs.sws_plate, fvs.sws_vehicle, fvs.sws_load, fvs.sws_productid, fvs.sws_quantity

FROM fv_orders as fvo INNER JOIN fv_products as fvp
INNER JOIN fv_sws as fvs WHERE status = 'Completed' 
AND fvo.date = '11/30/2016' 
AND fvo.order_num = fvs.sws_number 
AND fvs.sws_productid = fvp.product_id

我尝试在 phpMyAdmin 上运行它，但它给了我一个错误

1221 - UNION 和 LIMIT 使用不正确

对此的正确查询是什么？

_orders表

order_id (Primary)  int(11)                 
order_num           int(255)                    
Salesman            varchar(255)                    
salesman_name       varchar(255)                    
date                varchar(255)                
status              varchar(255)

_products 表

product_id (Primary)    int(11)                 
product_branch          varchar(255)                    
product_name            varchar(255)                    
description             varchar(255)                    
vatable                 tinyint(1)                  
critical_stock          int(11)             
quantity                int(11)                 
sell_price              double                  
category_id             int(11)                 
expiry_date             varchar(255)                    
date                    varchar(255)                    
isEmpty                 tinyint(1)                  
empties                 int(11) 

_sws 表

sws_id (Primary)    int(11) No              
sws_proname             varchar(255)                    
sws_isEmpty             tinyint(1)                  
sws_category            int(11)                 
sws_unitprice           double                  
sws_prodesc             varchar(255)                    
sws_proexp              varchar(255)                    
sws_vat                tinyint(1)               
sws_number             int(255)                 
date                    varchar(255)                    
sws_salesman            varchar(255)            
sws_route   varchar(255)                    
sws_smname  varchar(255)                    
sws_driver  varchar(255)                    
sws_plate   varchar(255)                
sws_vehicle varchar(255)                    
sws_load        int(255)                
sws_productid   int(255)                    
sws_quantity    int(255)    

Answer 1

使用 UNION 时，每个子查询中的列数必须相同，并且它们必须具有相同的数据类型。

您需要调整您的查询，以便您不使用*，而是定义每个表中的每一列。

有关详细信息，请参阅以下内容：

• http://www.mysqltutorial.org/sql-union-mysql.aspx
• https://dev.mysql.com/doc/refman/5.7/en/union.html

为了使用 UNION 运算符，您需要遵循一些规则：

• 在相应的 SELECT 语句中出现的列数必须相等。
• 出现在每个 SELECT 语句的相应位置的列必须具有相同的数据类型，或者至少是可转换的数据类型。

Answer 2

你需要重新考虑你的计划。

要进行联合，您需要具有相同名称和数据类型的字段。您不能简单地选择 * 并期望不同的表组合在一个结果集中。

您可能需要更改名称或在选择的不同部分添加虚拟列才能使其正常工作。

如果您发布表结构和字段名称，人们可能会为您提供更多帮助。