我需要在SQL Server数据库中删除一个高度引用的表。我如何才能得到所有外键约束的列表,我将需要删除以便删除表?
(SQL比在管理工作室的GUI中点击更可取)
我需要在SQL Server数据库中删除一个高度引用的表。我如何才能得到所有外键约束的列表,我将需要删除以便删除表?
(SQL比在管理工作室的GUI中点击更可取)
当前回答
SQL Server中所有引用给定表的外键列表:
您可以通过以下查询获得引用表名和列名…
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) = 'TableName'
下面的截图让你理解…
其他回答
以下是我认为在SQL Server 2016中处理这种情况的最佳实践。
你必须列出外键使用:
EXEC sp_fkeys 'TableName'
在这里你可以看到fk的全部信息。注意列FKTABLE_NAME, FKCOLUMN_NAME, FK_NAME, UPDATE_RULE, DELETE_RULE是你需要删除外键并在截断后再次实现它们的信息。
你可以组织一个脚本如下:
-- EXEC sp_fkeys 'TableName'
-- DROP CONSTRAINTS: I drop one, here drop every constraint you desire.
BEGIN TRANSACTION
GO
ALTER TABLE dbo.TableName
DROP CONSTRAINT IF EXISTS FK_TableName_OtherTable
GO
ALTER TABLE dbo.TableName SET (LOCK_ESCALATION = TABLE)
GO
COMMIT
-- TRUNCATE
BEGIN TRANSACTION
TRUNCATE TABLE TableName
GO
COMMIT
-- RECREATE CONSTRAINTS: I recreate 1, here recreate every fk you desire
BEGIN TRANSACTION
GO
ALTER TABLE dbo.TableName SET (LOCK_ESCALATION = TABLE)
GO
ALTER TABLE dbo.TableName ADD CONSTRAINT
FK_TableName_OtherTable FOREIGN KEY
(
Id_FK
) REFERENCES dbo.OtherTable
(
Id
) ON UPDATE NO ACTION
ON DELETE NO ACTION
GO
COMMIT
** UPDATE_RULE和DELETE_RULE的值可以在sp_fkeys的文档中看到:
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;
SQL Server中所有引用给定表的外键列表:
您可以通过以下查询获得引用表名和列名…
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) = 'TableName'
下面的截图让你理解…
试试这个:
sp_help 'TableName'
上面有一些不错的答案。但我更喜欢一个问题就能得到答案。 这段代码来自sys. .Sp_helpconstraint (sys proc)
这是微软查找是否有与tbl关联的外键的方法。
--setup variables. Just change 'Customer' to tbl you want
declare @objid int,
@objname nvarchar(776)
select @objname = 'Customer'
select @objid = object_id(@objname)
if exists (select * from sys.foreign_keys where referenced_object_id = @objid)
select 'Table is referenced by foreign key' =
db_name() + '.'
+ rtrim(schema_name(ObjectProperty(parent_object_id,'schemaid')))
+ '.' + object_name(parent_object_id)
+ ': ' + object_name(object_id)
from sys.foreign_keys
where referenced_object_id = @objid
order by 1
答案看起来像这样:test_db_name.dbo。账户:FK_Account_Customer