SQL Server：如何从information_schema获取外键引用？

在SQL Server中，如何从外键获取引用的表+列名称？

注意：不是密钥所在的表/列，而是所指的密钥。

例：

当表[T_ALV_Ref_FilterDisplay]的键[FA_MDT_ID]时。 指的是[T_AP_Ref_Customer].[MDT_ID]

比如创build这样一个约束的时候：

 ALTER TABLE [dbo].[T_ALV_Ref_FilterDisplay] WITH CHECK ADD CONSTRAINT [FK_T_ALV_Ref_FilterDisplay_T_AP_Ref_Customer] FOREIGN KEY([FA_MDT_ID]) REFERENCES [dbo].[T_AP_Ref_Customer] ([MDT_ID]) GO 

当给定[T_ALV_Ref_FilterAnzeige].[FA_MDT_ID]作为input时，我需要获得[T_AP_Ref_Customer].[MDT_ID]

Answer 1

没关系，这是正确的答案：
http://msdn.microsoft.com/en-us/library/aa175805(SQL.80).aspx

 SELECT KCU1.CONSTRAINT_NAME AS FK_CONSTRAINT_NAME ,KCU1.TABLE_NAME AS FK_TABLE_NAME ,KCU1.COLUMN_NAME AS FK_COLUMN_NAME ,KCU1.ORDINAL_POSITION AS FK_ORDINAL_POSITION ,KCU2.CONSTRAINT_NAME AS REFERENCED_CONSTRAINT_NAME ,KCU2.TABLE_NAME AS REFERENCED_TABLE_NAME ,KCU2.COLUMN_NAME AS REFERENCED_COLUMN_NAME ,KCU2.ORDINAL_POSITION AS REFERENCED_ORDINAL_POSITION FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS AS RC INNER JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE AS KCU1 ON KCU1.CONSTRAINT_CATALOG = RC.CONSTRAINT_CATALOG AND KCU1.CONSTRAINT_SCHEMA = RC.CONSTRAINT_SCHEMA AND KCU1.CONSTRAINT_NAME = RC.CONSTRAINT_NAME INNER JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE AS KCU2 ON KCU2.CONSTRAINT_CATALOG = RC.UNIQUE_CONSTRAINT_CATALOG AND KCU2.CONSTRAINT_SCHEMA = RC.UNIQUE_CONSTRAINT_SCHEMA AND KCU2.CONSTRAINT_NAME = RC.UNIQUE_CONSTRAINT_NAME AND KCU2.ORDINAL_POSITION = KCU1.ORDINAL_POSITION 

Answer 2

如果您可以使用SQL Server特定的模式目录视图，则此查询将返回您正在查找的内容：

 SELECT fk.name, OBJECT_NAME(fk.parent_object_id) 'Parent table', c1.name 'Parent column', OBJECT_NAME(fk.referenced_object_id) 'Referenced table', c2.name 'Referenced column' FROM sys.foreign_keys fk INNER JOIN sys.foreign_key_columns fkc ON fkc.constraint_object_id = fk.object_id INNER JOIN sys.columns c1 ON fkc.parent_column_id = c1.column_id AND fkc.parent_object_id = c1.object_id INNER JOIN sys.columns c2 ON fkc.referenced_column_id = c2.column_id AND fkc.referenced_object_id = c2.object_id 

不知道如何 – 如果有的话 – 您可以从INFORMATION_SCHEMA视图中获得相同的信息….

Answer 3

我想要一个版本，让我find所有的“关键”和“身份证”列有/约束。 所以我想所有的列相比，所有的PK 或 FK 或空列表，这里是我的查询。 希望它能帮助别人！

 SELECT c.table_schema ,c.table_name ,c.column_name ,KeyConstraints.constraint_type ,KeyConstraints.constraint_schema ,KeyConstraints.constraint_name ,KeyConstraints.referenced_table_schema ,KeyConstraints.referenced_table_name ,KeyConstraints.referenced_column_name ,KeyConstraints.update_rule ,KeyConstraints.delete_rule FROM information_schema.columns AS c LEFT JOIN ( SELECT FK.table_schema AS TABLE_SCHEMA ,FK.table_name ,CU.column_name ,FK.constraint_type ,c.constraint_schema ,C.constraint_name ,PK.table_schema AS REFERENCED_TABLE_SCHEMA ,PK.table_name AS REFERENCED_TABLE_NAME ,CCU.column_name AS REFERENCED_COLUMN_NAME ,C.update_rule ,C.delete_rule FROM information_schema.referential_constraints AS C INNER JOIN information_schema.table_constraints AS FK ON C.constraint_name = FK.constraint_name INNER JOIN information_schema.table_constraints AS PK ON C.unique_constraint_name = PK.constraint_name INNER JOIN information_schema.key_column_usage AS CU ON C.constraint_name = CU.constraint_name INNER JOIN information_schema.constraint_column_usage AS CCU ON PK.constraint_name = CCU.constraint_name WHERE ( FK.constraint_type = 'FOREIGN KEY' ) UNION SELECT ccu.table_schema ,ccu.table_name ,ccu.column_name ,tc.constraint_type ,ccu.constraint_schema ,ccu.constraint_name ,NULL ,NULL ,NULL ,NULL ,NULL FROM information_schema.constraint_column_usage ccu INNER JOIN information_schema.table_constraints tc ON ccu.table_schema = tc.table_schema AND ccu.table_name = tc.table_name WHERE tc.constraint_type = 'PRIMARY KEY' ) AS KeyConstraints ON c.table_schema = KeyConstraints.table_schema AND c.table_name = KeyConstraints.table_name AND c.column_name = KeyConstraints.column_name WHERE c.column_name LIKE '%ID' OR c.column_name LIKE '%Key' ORDER BY c.table_schema ,c.table_name ,c.column_name ; 

格式礼貌： http : //www.dpriver.com/pp/sqlformat.htm