mysql - SQL 查询字符串中的可选变量

Question

我正在自动化 Excel，并且我有一个字符串，我从工作表中读取输入作为 Variable1,2,3,4,5,6

我希望将它们设为可选，如果它们留空，查询将照常执行

  SELECT LEFT(Name, 5) 
  FROM Production.Product
  where 
  product.name like 'Variable1'
  product.brand like 'Variable2'
  prodcut.price > 'Variable3'
  prodcut.expirydate > 'Variable4'
  ORDER BY ProductID;

Answer 1

尝试这样的事情:

SELECT LEFT(Name, 5) 
FROM Production.Product
WHERE
(Product.name like @Variable1 or @Variable1 IS NULL) AND
(Product.brand like @Variable2 or @Variable2 IS NULL) AND
(Product.price > @Variable3 or @Variable3 IS NULL) AND
(Product.expirydate > @Variable4 or @Variable4 IS NULL)
ORDER BY ProductID;