Question

我正在尝试删除一个表但收到以下消息：

Msg 3726，Level 16，State 1，Line 3
  无法删除对象＆＃39; dbo.UserProfile＆＃39;因为它是由FOREIGN KEY约束引用的   Msg 2714，Level 16，State 6，Line 2
  已有一个名为＆＃39; UserProfile＆＃39;在数据库中。

我查看了SQL Server Management Studio但我无法找到约束。如何找出外键约束？

Answer 1

这是：

SELECT 
   OBJECT_NAME(f.parent_object_id) TableName,
   COL_NAME(fc.parent_object_id,fc.parent_column_id) ColName
FROM 
   sys.foreign_keys AS f
INNER JOIN 
   sys.foreign_key_columns AS fc 
      ON f.OBJECT_ID = fc.constraint_object_id
INNER JOIN 
   sys.tables t 
      ON t.OBJECT_ID = fc.referenced_object_id
WHERE 
   OBJECT_NAME (f.referenced_object_id) = 'YourTableName'

这样，您将获得引用表和列名称。

根据评论建议编辑使用sys.tables而不是通用sys.objects。谢谢，marc_s

Answer 2

另一种方法是检查

的结果

sp_help 'TableName'

（或只是突出显示引用的TableName和pres ALT + F1）

随着时间的推移，我决定改进我的答案。以下是sp_help提供的结果的屏幕截图。 A在此示例中使用了AdventureWorksDW2012数据库。那里有很多好的信息，我们正在寻找的是最后的 - 以绿色突出显示：

Answer 3

试试这个

SELECT
  object_name(parent_object_id) ParentTableName,
  object_name(referenced_object_id) RefTableName,
  name 
FROM sys.foreign_keys
WHERE parent_object_id = object_id('Tablename')

Answer 4

我发现这个答案很简单，并且根据我的需要做了诀窍：https://stackoverflow.com/a/12956348/652519

链接摘要，使用此查询：

EXEC sp_fkeys 'TableName'

快速而简单。我能够很快找到15个表的所有外键表，各自的列和外键名。

正如@mdisibio在下面提到的，这里有一个指向文档的链接，详细说明了可以使用的不同参数：https://docs.microsoft.com/en-us/sql/relational-databases/system-stored-procedures/sp-fkeys-transact-sql

Answer 5

我正在使用此脚本查找与外键相关的所有详细信息。我正在使用INFORMATION.SCHEMA。下面是一个SQL脚本：

SELECT 
    ccu.table_name AS SourceTable
    ,ccu.constraint_name AS SourceConstraint
    ,ccu.column_name AS SourceColumn
    ,kcu.table_name AS TargetTable
    ,kcu.column_name AS TargetColumn
FROM INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE ccu
    INNER JOIN INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS rc
        ON ccu.CONSTRAINT_NAME = rc.CONSTRAINT_NAME 
    INNER JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE kcu 
        ON kcu.CONSTRAINT_NAME = rc.UNIQUE_CONSTRAINT_NAME  
ORDER BY ccu.table_name

Answer 6

这是查找所有数据库中的外键关系的最佳方法。

exec sp_helpconstraint 'Table Name'

还有一种方式

select * from INFORMATION_SCHEMA.KEY_COLUMN_USAGE where TABLE_NAME='Table Name'
--and left(CONSTRAINT_NAME,2)='FK'(If you want single key)

Answer 7

如果您想在对象资源管理器窗口中通过SSMS，请右键单击要删除的对象，查看依赖项。

Answer 8

SELECT 
    obj.name      AS FK_NAME,
    sch.name      AS [schema_name],
    tab1.name     AS [table],
    col1.name     AS [column],
    tab2.name     AS [referenced_table],
    col2.name     AS [referenced_column]
FROM 
     sys.foreign_key_columns fkc
INNER JOIN sys.objects obj
    ON obj.object_id = fkc.constraint_object_id
INNER JOIN sys.tables tab1
    ON tab1.object_id = fkc.parent_object_id
INNER JOIN sys.schemas sch
    ON tab1.schema_id = sch.schema_id
INNER JOIN sys.columns col1
    ON col1.column_id = parent_column_id AND col1.object_id = tab1.object_id
INNER JOIN sys.tables tab2
    ON tab2.object_id = fkc.referenced_object_id
INNER JOIN sys.columns col2
    ON col2.column_id = referenced_column_id 
        AND col2.object_id =  tab2.object_id;

Answer 9

- 以下内容可能会为您提供更多您正在寻找的内容：

create Procedure spShowRelationShips 
( 
    @Table varchar(250) = null,
    @RelatedTable varchar(250) = null
)
as
begin
    if @Table is null and @RelatedTable is null
        select  object_name(k.constraint_object_id) ForeginKeyName, 
                object_name(k.Parent_Object_id) TableName, 
                object_name(k.referenced_object_id) RelatedTable, 
                c.Name RelatedColumnName,  
                object_name(rc.object_id) + '.' + rc.name RelatedKeyField
        from sys.foreign_key_columns k
        left join sys.columns c on object_name(c.object_id) = object_name(k.Parent_Object_id) and c.column_id = k.parent_column_id
        left join sys.columns rc on object_name(rc.object_id) = object_name(k.referenced_object_id) and rc.column_id = k.referenced_column_id
        order by 2,3

    if @Table is not null and @RelatedTable is null
        select  object_name(k.constraint_object_id) ForeginKeyName, 
                object_name(k.Parent_Object_id) TableName, 
                object_name(k.referenced_object_id) RelatedTable, 
                c.Name RelatedColumnName,  
                object_name(rc.object_id) + '.' + rc.name RelatedKeyField
        from sys.foreign_key_columns k
        left join sys.columns c on object_name(c.object_id) = object_name(k.Parent_Object_id) and c.column_id = k.parent_column_id
        left join sys.columns rc on object_name(rc.object_id) = object_name(k.referenced_object_id) and rc.column_id = k.referenced_column_id
        where object_name(k.Parent_Object_id) =@Table
        order by 2,3

    if @Table is null and @RelatedTable is not null
        select  object_name(k.constraint_object_id) ForeginKeyName, 
                object_name(k.Parent_Object_id) TableName, 
                object_name(k.referenced_object_id) RelatedTable, 
                c.Name RelatedColumnName,  
                object_name(rc.object_id) + '.' + rc.name RelatedKeyField
        from sys.foreign_key_columns k
        left join sys.columns c on object_name(c.object_id) = object_name(k.Parent_Object_id) and c.column_id = k.parent_column_id
        left join sys.columns rc on object_name(rc.object_id) = object_name(k.referenced_object_id) and rc.column_id = k.referenced_column_id
        where object_name(k.referenced_object_id) =@RelatedTable
        order by 2,3



end

Answer 10

您还可以通过调整@LittleSweetSeas答案来返回有关Foreign Keys的所有信息：

SELECT 
   OBJECT_NAME(f.parent_object_id) ConsTable,
   OBJECT_NAME (f.referenced_object_id) refTable,
   COL_NAME(fc.parent_object_id,fc.parent_column_id) ColName
FROM 
   sys.foreign_keys AS f
INNER JOIN 
   sys.foreign_key_columns AS fc 
      ON f.OBJECT_ID = fc.constraint_object_id
INNER JOIN 
   sys.tables t 
      ON t.OBJECT_ID = fc.referenced_object_id
order by
ConsTable

Answer 11

在SQL Server Management Studio中，您只需右键单击中的表即可对象资源管理器并选择“查看依赖项”。这会给你一个良好的起点。它显示了引用的表，视图和过程桌子。

Answer 12

在“对象资源管理器”中，展开表，然后展开“键”：

Answer 13

尝试以下查询。

select object_name(sfc.constraint_object_id) AS constraint_name,
       OBJECT_Name(parent_object_id) AS table_name ,
       ac1.name as table_column_name,
       OBJECT_name(referenced_object_id) as reference_table_name,      
       ac2.name as reference_column_name
from  sys.foreign_key_columns sfc
join sys.all_columns ac1 on (ac1.object_id=sfc.parent_object_id and ac1.column_id=sfc.parent_column_id)
join sys.all_columns ac2 on (ac2.object_id=sfc.referenced_object_id and ac2.column_id=sfc.referenced_column_id) 
where sfc.parent_object_id=OBJECT_ID(<main table name>);

这将给出将要引用的constraint_name，column_names，并且将依赖于约束的表将存在。

Answer 14

您可以使用此查询来显示Foreign key constaraints：

SELECT
K_Table = FK.TABLE_NAME,
FK_Column = CU.COLUMN_NAME,
PK_Table = PK.TABLE_NAME,
PK_Column = PT.COLUMN_NAME,
Constraint_Name = C.CONSTRAINT_NAME
FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS C
INNER JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS FK ON C.CONSTRAINT_NAME = FK.CONSTRAINT_NAME
INNER JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS PK ON C.UNIQUE_CONSTRAINT_NAME = PK.CONSTRAINT_NAME
INNER JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE CU ON C.CONSTRAINT_NAME = CU.CONSTRAINT_NAME
INNER JOIN (
SELECT i1.TABLE_NAME, i2.COLUMN_NAME
FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS i1
INNER JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE i2 ON i1.CONSTRAINT_NAME = i2.CONSTRAINT_NAME
WHERE i1.CONSTRAINT_TYPE = 'PRIMARY KEY'
) PT ON PT.TABLE_NAME = PK.TABLE_NAME
---- optional:
ORDER BY
1,2,3,4
WHERE PK.TABLE_NAME='YourTable'

取自http://blog.sqlauthority.com/2006/11/01/sql-server-query-to-display-foreign-key-relationships-and-name-of-the-constraint-for-each-table-in-database/

Answer 15

获取表格Primary Key和Foreign Key的最简单方法是：

/*  Get primary key and foreign key for a table */
USE DatabaseName;

SELECT CONSTRAINT_NAME FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE
WHERE CONSTRAINT_NAME LIKE 'PK%' AND
TABLE_NAME = 'TableName'

SELECT CONSTRAINT_NAME FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE
WHERE CONSTRAINT_NAME LIKE 'FK%' AND
TABLE_NAME = 'TableName'

如何找出FOREIGN KEY约束引用SQL Server中的表？

15 个答案: