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

@BankZ的最好回答

sp_help 'TableName'   

另外,对于不同的模式

sp_help 'schemaName.TableName'   

其他回答

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

你可以通过以下查询找到:

 SELECT OBJECT_NAME (FK.referenced_object_id) 'Referenced Table', 
      OBJECT_NAME(FK.parent_object_id) 'Referring Table', FK.name 'Foreign Key', 
      COL_NAME(FK.referenced_object_id, FKC.referenced_column_id) 'Referenced Column',
      COL_NAME(FK.parent_object_id,FKC.parent_column_id) 'Referring Column'
     FROM sys.foreign_keys AS FK
             INNER JOIN sys.foreign_key_columns AS FKC 
                 ON FKC.constraint_object_id = FK.OBJECT_ID
     WHERE OBJECT_NAME (FK.referenced_object_id) = 'YourTableName'
     AND COL_NAME(FK.referenced_object_id, FKC.referenced_column_id) = 'YourColumnName'
     order by  OBJECT_NAME(FK.parent_object_id)

也试一试。

EXEC sp_fkeys 'tableName', 'schemaName'

使用sp_fkeys,不仅可以通过pk表名和模式过滤结果,还可以通过fk表名和模式过滤结果。链接

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

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'