Question

我的问题很简单，如何列出SQL Server 用户定义表类型的主键（列名）？

离;

CREATE TYPE [dbo].[MyTableType] AS TABLE
(
    [ID] int NOT NULL, PRIMARY KEY CLUSTERED ( [ID])
)

如何使用查询

获取列[ID]

似乎只能找到真实表的主键，而不是表类型。

Answer 1

这存储在目录视图中：

SELECT  c.Name
FROM    sys.table_types AS tt
        INNER JOIN sys.key_constraints AS kc
            ON kc.parent_object_id = tt.type_table_object_id
        INNER JOIN sys.indexes AS i
            ON i.object_id = kc.parent_object_id
            AND i.index_id = kc.unique_index_id
        INNER JOIN sys.index_columns AS ic
            ON ic.object_id = kc.parent_object_id
        INNER JOIN sys.columns AS c
            ON c.object_id = ic.object_id
            AND c.column_id = ic.column_id
WHERE   tt.Name = 'YourTypeName';

Answer 2

用户定义的表格不是实际的表格，因此它在sys.table_types中有一个条目，而不在sys.tables中。

如果使用sys.key_constraints和sys.table_types.type_table_object_id字段，则可以使用其他表格从sys.key_constraints.parent_object_id检索关键信息，例如：

create TYPE TestTableType AS TABLE 
( 
    ID int primary key,
    Name nVARCHAR(50)
)

declare @typeID int

select @typeId=type_table_object_id 
from sys.table_types
where name='TestTableType'

select @typeId
-- Returns 1134627085

select * 
from sys.key_constraints
where parent_object_id=@typeID

-- Returns 
-- PK__TT_TestT__3214EC27BA14A4A6   1150627142  NULL    4   1134627085  PK  PRIMARY_KEY_CONSTRAINT  2016-04-25 17:36:34.890 2016-04-25 17:36:34.890 1   0   0   1   1

之后，您可以通过加入sys.index_columns和sys.columns来获得与其他主键相同的列名：

select col.name
from sys.key_constraints kcon
    inner join sys.index_columns indcol on indcol.object_id=kcon.parent_object_id
    inner join sys.columns col on col.object_id = kcon.parent_object_id 
               and col.column_id = indcol.column_id
where parent_object_id=@typeID

或者

select col.name
from sys.table_types tt 
    inner join sys.key_constraints kcon on type_table_object_id=kcon.parent_object_id
    inner join sys.index_columns indcol on indcol.object_id=kcon.parent_object_id
    inner join sys.columns col on col.object_id = kcon.parent_object_id and col.column_id = indcol.column_id
where tt.name='TestTableType'

如何列出SQL Server用户定义表类型的主键？

2 个答案: