Mysql sql语法错误计数

我有这个查询来计算股票

SELECT (receipt_count - COALESCE(sales_count, 0)) AS 'stock'
FROM (
SELECT SUM(spares_receipt.aantal_ontvangen) AS 'receipt_count'
FROM spares_receipt WHERE Number = 1001000 
) AS 'Receipt'
LEFT JOIN
(
SELECT SUM(spares_sales.aantal_verkocht) AS 'sales_count'
FROM spares_sales WHERE onderdeel_nummer = 1001000
) AS 'Sales'

但我得到了这个错误：

SELECT (receipt_count - COALESCE(sales_count, 0)) AS 'stock'
FROM (
    SELECT SUM(spares_receipt.aantal_ontvangen) AS 'receipt_count'
    FROM spares_receipt WHERE Number = 1001000 
) AS 'Receipt'
LEFT JOIN
 (
    SELECT SUM(spares_sales.aantal_verkocht) AS 'sales_count'
    FROM spares_sales WHERE onderdeel_nummer = 1001000
) AS 'Sales'
 LIMIT 0, 25 
MySQL meldt: Documentatie

#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''Receipt'
LEFT JOIN
(
    SELECT SUM(spares_sales.aantal_verkocht) AS 'sales_co' at line 5 

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但是我的代码有什么错呢？

别名必须是双引号，而不是单引号：

SELECT (receipt_count - COALESCE(sales_count, 0)) AS `stock`
FROM (
SELECT SUM(spares_receipt.aantal_ontvangen) AS `receipt_count`
FROM spares_receipt WHERE Number = 1001000 
) AS `Receipt`
LEFT JOIN
(
SELECT SUM(spares_sales.aantal_verkocht) AS `sales_count`
FROM spares_sales WHERE onderdeel_nummer = 1001000
) AS `Sales`

---

或者，您可以完全省略勾号而不使用任何内容。

只需一个注释-在查询的选择列表中，您可以使用单引号。不过，在其他任何地方，您都必须使用标识符引号，或者将其视为字符串而不是引用。这就是为什么错误发生在收据上，而不是在库存或收据计数上。根据您的代码，我得到这个错误：选择收据计数-合并销售计数，0作为库存从选择SUMspares\u receipt.aantal\u ontvangen作为库存从备件\u receipt中计数从备件\u receipt中计数，其中Number=1001000作为收据左侧加入选择SUMspares\u sales.aantal\u verkocht作为销售从备件\u sales中计数从onderdeel\u nummer=1001000作为销售限额0,25 MySQL meldt:Documentatie 1064-您的SQL语法有错误；检查与MySQL服务器版本对应的手册，以了解第11行“LIMIT 0，25”附近要使用的正确语法