下面是我将使用的SQL代码。

SELECT 
   f.name AS 'Name of Foreign Key',
   OBJECT_NAME(f.parent_object_id) AS 'Table name',
   COL_NAME(fc.parent_object_id,fc.parent_column_id) AS 'Fieldname',
   OBJECT_NAME(t.object_id) AS 'References Table name',
   COL_NAME(t.object_id,fc.referenced_column_id) AS 'References fieldname',

   'ALTER TABLE [' + OBJECT_NAME(f.parent_object_id) + ']  DROP CONSTRAINT [' + f.name + ']' AS 'Delete foreign key',

   'ALTER TABLE [' + OBJECT_NAME(f.parent_object_id) + ']  WITH NOCHECK ADD CONSTRAINT [' + 
        f.name + '] FOREIGN KEY([' + COL_NAME(fc.parent_object_id,fc.parent_column_id) + ']) REFERENCES ' + 
        '[' + OBJECT_NAME(t.object_id) + '] ([' +
        COL_NAME(t.object_id,fc.referenced_column_id) + '])' AS 'Create foreign key'
    -- , delete_referential_action_desc AS 'UsesCascadeDelete'
FROM sys.foreign_keys AS f,
     sys.foreign_key_columns AS fc,
     sys.tables t 
WHERE f.OBJECT_ID = fc.constraint_object_id
AND t.OBJECT_ID = fc.referenced_object_id
AND OBJECT_NAME(t.object_id) = 'Employees'      --  Just show the FKs which reference a particular table
ORDER BY 2

这不是特别清晰的SQL，所以让我们看一个例子。

所以，假设我想删除Microsoft心爱的Northwind数据库中的Employees表，但是SQL Server告诉我一个或多个外键阻止我这样做。

上面的SQL命令将返回这些结果…

它显示有3个外键引用雇员表。换句话说，除非先删除这三个外键，否则不允许删除(删除)这个表。

在结果中，第一行是以下外键约束在结果中的显示方式。

ALTER TABLE [dbo].[Employees]  WITH NOCHECK 
ADD CONSTRAINT [FK_Employees_Employees] FOREIGN KEY([ReportsTo])
REFERENCES [dbo].[Employees] ([EmployeeID])

倒数第二列显示了我需要使用的SQL命令来删除这些外键之一，例如:

ALTER TABLE [Employees] DROP CONSTRAINT [FK_Employees_Employees]

.．.右边一列显示了创建它的SQL…

ALTER TABLE [Employees] WITH NOCHECK 
ADD CONSTRAINT [FK_Employees_Employees] 
FOREIGN KEY([ReportsTo]) REFERENCES [Employees] ([EmployeeID])

使用所有这些命令，您就拥有了删除相关外键所需的一切，从而可以删除表，然后再重新创建它们。

唷。希望这能有所帮助。

这个答案建立在sp_fkeys的基础上，但格式化类似于sp_fkeys，适用于多个列并列出它们的顺序。

SELECT fk_obj.name    AS FK_NAME,
       pk_schema.name AS PKTABLE_OWNER,
       pk_table.name  AS PKTABLE_NAME,
       pk_column.name AS PKCOLUMN_NAME,
       fk_schema.name AS FKTABLE_OWNER,
       fk_table.name  AS FKTABLE_NAME,
       fk_column.name AS FKCOLUMN_NAME,
       ROW_NUMBER() over (
           PARTITION BY fk_obj.name, fk_schema.name
           ORDER BY fkc.constraint_column_id
           )          AS KEY_SEQ
FROM sys.foreign_key_columns fkc
         INNER JOIN sys.objects fk_obj
                    ON fk_obj.object_id = fkc.constraint_object_id
         INNER JOIN sys.tables fk_table
                    ON fk_table.object_id = fkc.parent_object_id
         INNER JOIN sys.schemas fk_schema
                    ON fk_table.schema_id = fk_schema.schema_id
         INNER JOIN sys.columns fk_column
                    ON fk_column.column_id = parent_column_id
                        AND fk_column.object_id = fk_table.object_id
         INNER JOIN sys.tables pk_table
                    ON pk_table.object_id = fkc.referenced_object_id
         INNER JOIN sys.schemas pk_schema
                    ON pk_table.schema_id = pk_schema.schema_id
         INNER JOIN sys.columns pk_column
                    ON pk_column.column_id = fkc.referenced_column_id
                        AND pk_column.object_id = pk_table.object_id;

Oracle SQL

select *
from
    all_constraints
where
    r_constraint_name in
    (select       constraint_name
    from
       all_constraints
    where
       table_name='PUT_THE_TABLE_NAME_HERE');

all_constraints是Oracle DB中的一个固有表名。

这将获得涉及所选表的任何外键。*假设为_FIRSTABLENAME_SECONDTABLENAME格式。

 declare @tablename as varchar(MAX)
 SET @tablename = 'yourtablename'
 SELECT name
 FROM YOURDATABASE.sys.objects
 WHERE type_desc = 'FOREIGN_KEY_CONSTRAINT' and (name LIKE '%_' + @tablename + 'empdb_%' or name LIKE '%_' + @tablename )

这是更一般的形式:

 SELECT name
 FROM YOURDATABASE_PROD.sys.objects
 WHERE type_desc = 'FOREIGN_KEY_CONSTRAINT' and name LIKE '%' + @tablename + '%' and
 name NOT LIKE '[a-zA-Z0-9]' + @tablename + '%' and name NOT LIKE '%' + @tablename + '[a-zA-Z0-9]' 

不知道为什么没有人建议，但我使用sp_fkeys查询给定表的外键:

EXEC sp_fkeys 'TableName'

你也可以指定模式:

EXEC sp_fkeys @pktable_name = 'TableName', @pktable_owner = 'dbo'

在没有指定模式的情况下，文档声明如下:

如果没有指定pktable_owner，则默认表可见性规则 的基础DBMS应用程序。 在SQL Server中，如果当前用户拥有一个具有指定 Name，返回该表的列。如果pktable_owner不是 且当前用户不拥有具有指定属性的表 Pktable_name时，该过程查找具有指定 由数据库所有者拥有的Pktable_name。如果存在，那张桌子就是 返回列。

SELECT
OBJECT_NAME(parent_object_id) 'Parent table',
c.NAME 'Parent column name',
OBJECT_NAME(referenced_object_id) 'Referenced table',
cref.NAME 'Referenced column name'
FROM 
sys.foreign_key_columns fkc 
INNER JOIN 
sys.columns c 
   ON fkc.parent_column_id = c.column_id 
      AND fkc.parent_object_id = c.object_id
INNER JOIN 
sys.columns cref 
   ON fkc.referenced_column_id = cref.column_id 
      AND fkc.referenced_object_id = cref.object_id  where   OBJECT_NAME(parent_object_id) = 'tablename'

如果你想获得所有表的外键关系，排除where子句，否则写你的tablename而不是tablename