sql - 请提供简单的SQL Server语法帮助

Question

我用这个把头撞在墙上。为什么SSMS中的查询编辑器在此查询末尾给我一个有关右括号的错误？

SELECT 
    c.TABLE_NAME,
    c.COLUMN_NAME
FROM 
    INFORMATION_SCHEMA.COLUMNS c
INNER JOIN 
    (SELECT COLUMN_NAME
     FROM INFORMATION_SCHEMA.COLUMNS
     GROUP BY COLUMN_NAME
     HAVING COUNT(*) = 1)

我收到此错误:

Incorrect syntax near ')'

Answer 1

您在括号中缺少子查询的别名和on子句:

SELECT 
    c.TABLE_NAME,
    c.COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS c
INNER JOIN 
    (SELECT 
        COLUMN_NAME
    FROM INFORMATION_SCHEMA.COLUMNS
    GROUP BY COLUMN_NAME
    HAVING COUNT(*) = 1
    ) x -- Alias added here
    ON x.COLUMN_NAME = c.COLUMN_NAME -- ON caluse