SQL 参数数据类型 int 对于 charindex 函数的参数 1 无效

Question

我正在尝试将 MySQL 查询转换为 MsSql 查询，但遇到了问题。这是我的查询：

MySQL

SELECT *,
(SELECT count(books.id)
   FROM books
   WHERE books.status = 1
     AND FIND_IN_SET(categories.id, books.multiple_category_id)) AS book_count
   FROM categories, books
   WHERE categories.parent_id=0
     AND categories.status=1 ;

我试过的 SQL

SELECT *,
  (SELECT count(books.id)
   FROM books
   WHERE books.status = 1
     AND CHARINDEX(categories.id, books.multiple_category_id) > 0) AS book_count
   FROM categories, books
   WHERE categories.parent_id=0
     AND categories.status=1 ;

我得到的错误是：

Argument data type int is invalid for argument 1 of charindex function.

以供参考。 http://sqlfiddle.com/#!3/4ed19/3

有没有人有任何想法？提前致谢！

Answer 1

使用此查询。我刚刚更改categories.id为CAST(categories.id AS VARCHAR). 因为id在表integer中categories。

SELECT *,
(SELECT count(books.id)
   FROM books
   WHERE books.status = 1
     AND CHARINDEX(CAST(categories.id AS VARCHAR), books.multiple_category_id) > 0) AS book_count
FROM categories,
     books
WHERE categories.parent_id=0
  AND categories.status=1 ;