查询以获取 SQL Server 2000 中的所有外键约束

Question

我需要查询 SQL Server 2000 以获取所有外键的列表。

尤其是指向特定列的所有外键。

如何编写此查询？

Answer 1

select * from sysobjects
where xtype = 'F'

我希望这样可以解决问题并与 SQL Server 2000 兼容！

如果您还需要 SQL Server 2000 中的表和列信息，则涉及更多；您需要像这样加入sysforeignkeys 和syscolumns 目录视图：

select
  so.name 'foreign key name',
  OBJECT_NAME(parent_obj) 'table',
  OBJECT_NAME(sf.fkeyid) 'referencing table',
  sc1.name 'referencing column',
  OBJECT_NAME(sf.rkeyid) 'referenced table',
  sc2.name 'referenced column'
from sysobjects so
inner join sysforeignkeys sf on so.id = sf.constid
inner join syscolumns sc1 on sf.fkeyid = sc1.id and sf.fkey = sc1.colid
inner join syscolumns sc2 on sf.rkeyid = sc2.id and sf.fkey = sc2.colid
where so.xtype in ('F','PK')

如果您想利用在 SQL Server 2000 中确实可用的 INFORMATION_SCHEMA 视图，请使用以下查询：

SELECT
    rc.CONSTRAINT_NAME,     
    rcu.TABLE_NAME 'Referencing Table', 
    rcu.COLUMN_NAME 'Referencing Column',
    rcu1.TABLE_NAME 'Referenced Table',
    rcu1.COLUMN_NAME 'Referenced Column'
FROM
    INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS rc
INNER JOIN 
    INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE rcu 
      ON rc.CONSTRAINT_CATALOG = rcu.CONSTRAINT_CATALOG 
         AND rc.CONSTRAINT_NAME = rcu.CONSTRAINT_NAME
INNER JOIN 
    INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE rcu1 
      ON rc.UNIQUE_CONSTRAINT_CATALOG = rcu1.CONSTRAINT_CATALOG 
         AND rc.UNIQUE_CONSTRAINT_NAME = rcu1.CONSTRAINT_NAME

马克

Answer 2

select * from INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS

如果您需要有关键的更多信息，可以将其加入到 INFORMATION_SCHEMA.KEY_COLUMN_USAGE 视图中，该视图包含键所引用的列。

Answer 3

查看 sp_helpconstraint 的来源以获得更多想法，但这应该可行...

获取每个引用目标表和列的 FK

• 替换“你的表名”
• 取消注释最后一个“AND”并设置您的目标列名称

代码：

--list all tables & columns that refer to the given table
select
    k.name,pt.Name AS ParentTable,pc.name,c.constraint_column_id,ct.Name AS ReferedToTable,c.referenced_column_id,cc.Name
    from sys.foreign_keys                  k
        INNER JOIN sys.foreign_key_columns c ON k.parent_object_id=c.parent_object_id
        INNER JOIN sys.objects             pt ON c.parent_object_id=pt.object_ID
        INNER JOIN sys.objects             ct ON c.referenced_object_id=ct.object_ID
        INNER JOIN  sys.columns            pc ON c.parent_object_id=pc.object_ID AND c.parent_column_id=pc.column_id
        INNER JOIN  sys.columns            cc ON c.referenced_object_id=cc.object_ID AND c.referenced_column_id=cc.column_id
    where k.referenced_object_id = object_id('YourTableName')
        --AND pc.name='YourColumnName' --parent table column name
        --AND cc.name='YourColumnName' --referenced table's column name