Question

如果它也是来自信息模式的外键，我想提取表的名称主键列像两张桌子一样：

Student 
std_id  std_name

和

PHDstudent
std_id   reaserchfield

PHDstudent中的std_id是同时引用Student表的主键和外键。

Answer 1

运行此查询

SELECT Tab.TABLE_NAME, Col.Column_Name from 
    INFORMATION_SCHEMA.TABLE_CONSTRAINTS Tab, 
    INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE Col 
WHERE 
    Col.Constraint_Name = Tab.Constraint_Name
    AND Col.Table_Name = Tab.Table_Name
    AND Constraint_Type = 'PRIMARY KEY '
INTERSECT
SELECT Tab.TABLE_NAME, Col.Column_Name from 
    INFORMATION_SCHEMA.TABLE_CONSTRAINTS Tab, 
    INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE Col 
WHERE 
    Col.Constraint_Name = Tab.Constraint_Name
    AND Col.Table_Name = Tab.Table_Name
    AND Constraint_Type = 'FOREIGN KEY '

Answer 2

SELECT s.std_id FROM Student s 
INNER JOIN PHDstudent p 
ON s.std_id = p.std_id

阅读INNER JOINS

Answer 3

我认为您询问的是主键列名称，而不应该使用下面的查询，它会为您提供主键列名称.....

<强> SELECT column_name FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE WHERE OBJECTPROPERTY(OBJECT_ID(constraint_name), 'IsPrimaryKey') = 1 AND table_name = 'PHDstudent'

SQL：检查主键是否为外键

3 个答案: