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
我在2008年及以后一直在使用它。它类似于列出的其他一些解决方案,但字段名称是适当的大小写,以处理特定于大小写的(LatBin)排序。此外,您可以为它提供一个表名,并检索该表的信息。
-->>SPECIFY THE DESIRED DB
USE ???
GO
/*********************************************************************************************
LIST OUT ALL PRIMARY AND FOREIGN KEY CONSTRAINTS IN A DB OR FOR A SPECIFIED TABLE
*********************************************************************************************/
DECLARE @tblName VARCHAR(255)
/*******************/
SET @tblName = NULL-->NULL will return all PK/FK constraints for every table in the database
/*******************/
SELECT PKTABLE_QUALIFIER = CONVERT(SYSNAME,DB_NAME()),
PKTABLE_OWNER = CONVERT(SYSNAME,SCHEMA_NAME(O1.schema_id)),
PKTABLE_NAME = CONVERT(SYSNAME,O1.name),
PKCOLUMN_NAME = CONVERT(SYSNAME,C1.name),
FKTABLE_QUALIFIER = CONVERT(SYSNAME,DB_NAME()),
FKTABLE_OWNER = CONVERT(SYSNAME,SCHEMA_NAME(O2.schema_id)),
FKTABLE_NAME = CONVERT(SYSNAME,O2.name),
FKCOLUMN_NAME = CONVERT(SYSNAME,C2.name),
-- Force the column to be non-nullable (see SQL BU 325751)
KEY_SEQ = isnull(convert(smallint,K.constraint_column_id),0),
UPDATE_RULE = CONVERT(SMALLINT,CASE OBJECTPROPERTY(F.object_id,'CnstIsUpdateCascade')
WHEN 1 THEN 0
ELSE 1
END),
DELETE_RULE = CONVERT(SMALLINT,CASE OBJECTPROPERTY(F.object_id,'CnstIsDeleteCascade')
WHEN 1 THEN 0
ELSE 1
END),
FK_NAME = CONVERT(SYSNAME,OBJECT_NAME(F.object_id)),
PK_NAME = CONVERT(SYSNAME,I.name),
DEFERRABILITY = CONVERT(SMALLINT,7) -- SQL_NOT_DEFERRABLE
FROM sys.all_objects O1,
sys.all_objects O2,
sys.all_columns C1,
sys.all_columns C2,
sys.foreign_keys F
INNER JOIN sys.foreign_key_columns K
ON (K.constraint_object_id = F.object_id)
INNER JOIN sys.indexes I
ON (F.referenced_object_id = I.object_id
AND F.key_index_id = I.index_id)
WHERE O1.object_id = F.referenced_object_id
AND O2.object_id = F.parent_object_id
AND C1.object_id = F.referenced_object_id
AND C2.object_id = F.parent_object_id
AND C1.column_id = K.referenced_column_id
AND C2.column_id = K.parent_column_id
AND ( O1.name = @tblName
OR O2.name = @tblName
OR @tblName IS null)
ORDER BY PKTABLE_NAME,FKTABLE_NAME
其他回答
以下的解决方案对我来说很有效:
--Eliminar las llaves foraneas
declare @query varchar(8000)
declare cursorRecorrerTabla cursor for
SELECT 'ALTER TABLE [PoaComFinH].['+sch.name+'].['+referencingTable.Name+'] DROP CONSTRAINT ['+foreignKey.name+']' 'query'
FROM PoaComFinH.sys.foreign_key_columns fk
JOIN PoaComFinH.sys.tables referencingTable ON fk.parent_object_id = referencingTable.object_id
JOIN PoaComFinH.sys.schemas sch ON referencingTable.schema_id = sch.schema_id
JOIN PoaComFinH.sys.objects foreignKey ON foreignKey.object_id = fk.constraint_object_id
JOIN PoaComFinH.sys.tables referencedTable ON fk.referenced_object_id = referencedTable.object_id
--3ro. abrir el cursor.
open cursorRecorrerTabla
fetch next from cursorRecorrerTabla
into @query
while @@fetch_status = 0
begin
--inicio cuerpo del cursor
print @query
exec(@query)
--fin cuerpo del cursor
fetch next from cursorRecorrerTabla
into @query
end
--cerrar cursor
close cursorRecorrerTabla
deallocate cursorRecorrerTabla
我知道这是一个很晚(非常晚)的回复,但我找到了这些简单的方法来找到所有的foreign_key_references。这是解决方案;
解决方案1:
EXEC SP_FKEYS 'MyTableName'; // It'll show you the all the information(in multiple tables) regarding to the TableName with all ForeignKey_References.
解决方案2:
EXEC SP_HELP 'MyTableName'; // It'll show all ForeignKey references in a single table.
解决方案03:
// It'll show you the Column_Name with Referenced_Table_Name
SELECT
COL_NAME(fc.parent_object_id,fc.parent_column_id) Column_Name,
OBJECT_NAME(f.parent_object_id) Table_Name
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) = 'MyTableName'
希望这对你有很大帮助。: -)
最简单的方法是使用sys。SQL中的foreign_keys_columns。这里的表包含了所有外键的对象ID,包括它们的引用列ID、引用表ID以及引用列和表。由于Id保持不变,因此对于Schema和表中的进一步修改,结果将是可靠的。
查询:
SELECT
OBJECT_NAME(fkeys.constraint_object_id) foreign_key_name
,OBJECT_NAME(fkeys.parent_object_id) referencing_table_name
,COL_NAME(fkeys.parent_object_id, fkeys.parent_column_id) referencing_column_name
,OBJECT_SCHEMA_NAME(fkeys.parent_object_id) referencing_schema_name
,OBJECT_NAME (fkeys.referenced_object_id) referenced_table_name
,COL_NAME(fkeys.referenced_object_id, fkeys.referenced_column_id)
referenced_column_name
,OBJECT_SCHEMA_NAME(fkeys.referenced_object_id) referenced_schema_name
FROM sys.foreign_key_columns AS fkeys
我们还可以使用where添加过滤器
WHERE OBJECT_NAME(fkeys.parent_object_id) = 'table_name' AND
OBJECT_SCHEMA_NAME(fkeys.parent_object_id) = 'schema_name'
最初的问题要求将所有外键的列表放入一个高度引用的表中,以便可以删除表。
这个小查询返回将所有外键放入特定表所需的“drop foreign key”命令:
SELECT
'ALTER TABLE ['+sch.name+'].['+referencingTable.Name+'] DROP CONSTRAINT ['+foreignKey.name+']' '[DropCommand]'
FROM sys.foreign_key_columns fk
JOIN sys.tables referencingTable ON fk.parent_object_id = referencingTable.object_id
JOIN sys.schemas sch ON referencingTable.schema_id = sch.schema_id
JOIN sys.objects foreignKey ON foreignKey.object_id = fk.constraint_object_id
JOIN sys.tables referencedTable ON fk.referenced_object_id = referencedTable.object_id
WHERE referencedTable.name = 'MyTableName'
示例输出:
[DropCommand]
ALTER TABLE [dbo].[OtherTable1] DROP CONSTRAINT [FK_OtherTable1_MyTable]
ALTER TABLE [dbo].[OtherTable2] DROP CONSTRAINT [FK_OtherTable2_MyTable]
省略where -子句以获取当前数据库中所有外键的删除命令。
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。