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

通过@Gishu所做的工作,我能够在SQL Server 2005中生成并使用以下SQL

SELECT t.name AS TableWithForeignKey, fk.constraint_column_id AS FK_PartNo, 
       c.name AS ForeignKeyColumn, o.name AS FK_Name 
  FROM sys.foreign_key_columns AS fk
       INNER JOIN sys.tables AS t ON fk.parent_object_id = t.object_id
       INNER JOIN sys.columns AS c ON fk.parent_object_id = c.object_id 
                                  AND fk.parent_column_id = c.column_id
       INNER JOIN sys.objects AS o ON fk.constraint_object_id = o.object_id
  WHERE fk.referenced_object_id = (SELECT object_id FROM sys.tables 
                                        WHERE name = 'TableOthersForeignKeyInto')
  ORDER BY TableWithForeignKey, FK_PartNo;

在一个查询中显示表,列和外键名称。

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

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。: -)

这将获得涉及所选表的任何外键。*假设为_FIRSTABLENAME_SECONDTABLENAME格式。

 declare @tablename as varchar(MAX)
 SET @tablename = 'yourtablename'
 SELECT name
 FROM YOURDATABASE.sys.objects
 WHERE type_desc = 'FOREIGN_KEY_CONSTRAINT' and (name LIKE '%_' + @tablename + 'empdb_%' or name LIKE '%_' + @tablename )

这是更一般的形式:

 SELECT name
 FROM YOURDATABASE_PROD.sys.objects
 WHERE type_desc = 'FOREIGN_KEY_CONSTRAINT' and name LIKE '%' + @tablename + '%' and
 name NOT LIKE '[a-zA-Z0-9]' + @tablename + '%' and name NOT LIKE '%' + @tablename + '[a-zA-Z0-9]' 

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。

SELECT
OBJECT_NAME(parent_object_id) 'Parent table',
c.NAME 'Parent column name',
OBJECT_NAME(referenced_object_id) 'Referenced table',
cref.NAME 'Referenced column name'
FROM 
sys.foreign_key_columns fkc 
INNER JOIN 
sys.columns c 
   ON fkc.parent_column_id = c.column_id 
      AND fkc.parent_object_id = c.object_id
INNER JOIN 
sys.columns cref 
   ON fkc.referenced_column_id = cref.column_id 
      AND fkc.referenced_object_id = cref.object_id  where   OBJECT_NAME(parent_object_id) = 'tablename'

如果你想获得所有表的外键关系,排除where子句,否则写你的tablename而不是tablename