我正在尝试删除表格,但收到以下消息:
消息 3726,第 16 级,状态 1,第 3 行
无法删除对象“dbo.UserProfile”,因为它由外键约束引用。
消息 2714,第 16 级,状态 6,第 2 行
数据库中已有一个名为“UserProfile”的对象。
我用 SQL Server Management Studio 环顾四周,但找不到约束。如何找出外键约束?
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,编辑为使用 sys.tables 而不是通用 sys.objects。 谢谢,马克_s
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')
我发现这个答案非常简单,并且满足了我的需要:https://stackoverflow.com/a/12956348/652519
链接中的摘要,使用此查询:
EXEC sp_fkeys 'TableName'
快速简单。我能够很快找到 15 个表的所有外键表、各自的列和外键名称。
正如 @mdisibio 下面指出的,这里有一个文档链接,详细介绍了可以使用的不同参数:https://learn.microsoft.com/en-us/sql/relational-databases/system-stored-procedures/ sp-fkeys-transact-sql
这是找出所有数据库中外键关系的最佳方法。
exec sp_helpconstraint 'Table Name'
还有一种方法
select * from INFORMATION_SCHEMA.KEY_COLUMN_USAGE where TABLE_NAME='Table Name'
--and left(CONSTRAINT_NAME,2)='FK'(If you want single key)
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
如果您想在对象资源管理器窗口上通过 SSMS,请右键单击要删除的对象,查看依赖关系。
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;
在 SQL Server Management Studio 中,您只需右键单击 对象资源管理器并选择“查看依赖关系”。这会给你一个 良好的起点。它显示引用的表、视图和过程 桌子。
获得桌子
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'
--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
您可以使用此查询来显示
Foreign key
约束:
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'
您还可以通过改编@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
流程
_sp_help 'tbl_name'_
确实提供了很多信息,但我找到了程序
_sp_fkeys 'tbl_name'_ and
_sp_pkeys 'tbl_name'_
更易于使用,并且可能具有更面向未来的结果。
(他们确实完美地回答了OP)
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constraint_name、将要引用的column_names以及将取决于约束的表。
Littlesweetsea 拥有我需要的东西,但通常了解架构是件好事。
SELECT schema_NAME(f.schema_id) schemaname,
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) = 'soldiers'