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Mysql 我怎样才能在这篇文章中阅读多个专栏_Mysql - Fatal编程技术网

Mysql 我怎样才能在这篇文章中阅读多个专栏

Mysql 我怎样才能在这篇文章中阅读多个专栏,mysql,Mysql,在1_产品t2中,我有其他列称为make,model 当我添加它们时 (SELECT t2.code,t2.make,t2.model FROM ..... 我明白了 错误1241操作数应包含1列 在内联查询中不能返回多个列。如果要为每个t1.fk_products_id返回多个列,则必须重写查询,如下所示: SELECT t1.fk_products_id, t2.code, t2.make, t2.model FROM 1_stock

在1_产品t2中,我有其他列称为make,model

当我添加它们时

(SELECT 
            t2.code,t2.make,t2.model
        FROM .....
我明白了

错误1241操作数应包含1列


在内联查询中不能返回多个列。如果要为每个t1.fk_products_id返回多个列,则必须重写查询,如下所示:

SELECT t1.fk_products_id,
  t2.code,
  t2.make,
  t2.model
FROM 1_stock t1
LEFT JOIN 1_products t2
  on t1.fk_products_id = t2.id
WHERE t1.branch = 1 
  and t1.dispatch <> 0;

所以问题应该是,在获取数据方面,您是否采取了正确的方法,那么子查询就没有意义了,是吗?你应该描述你想要什么,而不是在试图得到它的过程中出现的错误。
SELECT t1.fk_products_id,
  t2.code,
  t2.make,
  t2.model
FROM 1_stock t1
LEFT JOIN 1_products t2
  on t1.fk_products_id = t2.id
WHERE t1.branch = 1 
  and t1.dispatch <> 0;