如何列出表中的所有外键？答案

【问题标题】：How can I list all foreign keys in a Table?如何列出表中的所有外键？
【发布时间】：2018-05-16 09:27:37
【问题描述】：

假设，我知道数据库Database1 中表TableName1 的名称。

我要找：

该表具有的外键。
他们引用了哪些外部表。
他们引用了哪些外部列。
这些外来列的类型、大小等。

是否有任何可用的 sql server 查询（不是存储过程）？

注意：

答案是“How can I list all foreign keys referencing a given table in SQL Server?”不符合我的要求，因为他们接受的答案是一个存储过程，其余的没有返回或返回更少的结果。

例如，DailySale 表有两个外键，

但是这个查询

EXEC sp_fkeys 'TableName'

只列出一个。

【问题讨论】：

How can I list all foreign keys referencing a given table in SQL Server?的可能重复

标签： sql sql-server sql-server-2012

【解决方案1】：

下面的代码 sn-p 可以根据您的进一步要求进行一些使用和修改 - 这将提取列级详细信息，例如data type、length、precision、scale 等...

SELECT  obj.name AS FK_NAME,
    sch.name AS [schema_name],
    tab1.name AS [table],
    col1.name AS [column],
    tab2.name AS [referenced_table],
    col2.name AS [referenced_column],
    TY.[name] AS system_data_type, col1.[max_length],col1.[precision], col1.[scale], col1.[is_nullable], col1.[is_ansi_padded]
FROM sys.foreign_key_columns fkc
INNER JOIN sys.objects obj
    ON obj.object_id = fkc.constraint_object_id
INNER JOIN sys.tables tab1
    ON tab1.object_id = fkc.parent_object_id
INNER JOIN sys.schemas sch
    ON tab1.schema_id = sch.schema_id
INNER JOIN sys.columns col1
    ON col1.column_id = parent_column_id AND col1.object_id = tab1.object_id
INNER JOIN sys.tables tab2
    ON tab2.object_id = fkc.referenced_object_id
INNER JOIN sys.columns col2
    ON col2.column_id = referenced_column_id AND col2.object_id = tab2.object_id
INNER JOIN sys.[types] TY ON col1.[system_type_id] = TY.[system_type_id] AND col1.[user_type_id] = TY.[user_type_id] 
AND tab1.name = 'TableName1'

【讨论】：

【解决方案2】：

您可以将OBJECT_NAME(f.referenced_object_id) = 'tblpatientmaster' 与OBJECT_NAME(f.parent_object_id) = 'tblpatientmaster' 切换以获取此表的引用以引用此表。

--Reference in this table
     SELECT
        f.name constraint_name
       ,OBJECT_NAME(f.parent_object_id) referencing_table_name
       ,COL_NAME(fc.parent_object_id, fc.parent_column_id) referencing_column_name
       ,OBJECT_NAME (f.referenced_object_id) referenced_table_name
       ,COL_NAME(fc.referenced_object_id, fc.referenced_column_id) referenced_column_name

       , DATA_TYPE column_data_type
    FROM sys.foreign_keys AS f
    INNER JOIN sys.foreign_key_columns AS fc
       ON f.object_id = fc.constraint_object_id
    INNER JOIN INFORMATION_SCHEMA.COLUMNS col 
       ON COL_NAME(fc.parent_object_id, fc.parent_column_id) = col.COLUMN_NAME 
    where OBJECT_NAME(f.referenced_object_id) = 'YouTableName'
    ORDER BY f.name

-- 将此表引用到其他表

SELECT distinct
    f.name constraint_name
   ,OBJECT_NAME(f.parent_object_id) referencing_table_name
   ,COL_NAME(fc.parent_object_id, fc.parent_column_id) referencing_column_name
   ,OBJECT_NAME (f.referenced_object_id) referenced_table_name
   ,COL_NAME(fc.referenced_object_id, fc.referenced_column_id) referenced_column_name

   , DATA_TYPE column_data_type
FROM sys.foreign_keys AS f
INNER JOIN sys.foreign_key_columns AS fc
   ON f.object_id = fc.constraint_object_id
INNER JOIN INFORMATION_SCHEMA.COLUMNS col 
   ON COL_NAME(fc.parent_object_id, fc.parent_column_id) = col.COLUMN_NAME 
where OBJECT_NAME(f.parent_object_id) = 'YouTableName'
ORDER BY f.name

【讨论】：