sql - 如何在 where 子句中使用我的别名？

Question

我正在尝试在多列文本和备忘录中搜索某些我不想看到的短语和黑名单短语。

假设如下表

stories: 
id, title, author, publisher, content

例如。我想找到所有提到(在任何领域)“苹果”但将“苹果酱”列入黑名单的故事。

SELECT stories.id, [stories.title] & " " & [stories.author] & " " & [stories.publisher] & " " & [stories.memo] AS allMyText
FROM stories
WHERE ((([allMyText]) Like "*apples*" And ([allMyText]) Not Like "*applesauce*"));

如何在 where 子句中使用我的别名？我找不到有关该主题的任何文档:

1) 这种方法可行吗？
2) 替代方案是否意味着我将在每次行迭代时执行多个字符串连接？

Answer 1

I can't use my alias in the where clause.

1.这种方法可行吗？

当然，把它放在子查询中。

SELECT *
FROM
(
SELECT stories.id, [stories.title] & " " & [stories.author] & " " & [stories.publisher] & " " & [stories.memo] AS allMyText
FROM stories
) AS SUBQ
WHERE ((([allMyText]) Like "*apples*" And ([allMyText]) Not Like "*applesauce*"));

2. 替代方案是否意味着我将在每次行迭代时执行多个字符串连接？

是的，没错，替代方法是重复表达式。我不会用这个替代方案的代码让你厌烦。

对于您的特定查询，您也可以使用此

SELECT stories.id, [stories.title] & " " & [stories.author] & " " & [stories.publisher] & " " & [stories.memo] AS allMyText
FROM stories
WHERE ([stories.title] Like "*apples*" OR [stories.author] Like "*apples*" 
  OR [stories.publisher] Like "*apples*" OR [stories.memo] Like "*apples*")
AND NOT ([stories.title] Like "*applesauce*" OR [stories.author] Like "*applesauce*"
  OR [stories.publisher] Like "*applesauce*" OR [stories.memo] Like "*applesauce*")