Jus*_*ick 11 sql t-sql sql-server
假设我有一个视图,其中一些列名是别名,例如本例中的"surName":
CREATE VIEW myView AS
SELECT
firstName,
middleName,
you.lastName surName
FROM
myTable me
LEFT OUTER JOIN yourTable you
ON me.code = you.code
GO
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我可以使用INFORMATION_SCHEMA视图检索有关视图的一些信息.
例如,查询
SELECT column_name AS ALIAS, data_type AS TYPE
FROM information_schema.columns
WHERE table_name = 'myView'
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收益率:
---------------- |ALIAS |TYPE | ---------------- |firstName |nchar| |middleName|nchar| |surName |nchar| ----------------
但是,我想知道实际的列名.理想的情况是:
--------------------------- |ALIAS |TYPE |REALNAME | --------------------------- |firstName |nchar|firstName | |middleName|nchar|middleName| |surName |nchar|lastName | ---------------------------
如何根据别名确定实际列名称是什么? 必须有一些方法来使用sys表和/或INFORMATION_SCHEMA视图来检索此信息.
编辑: 我可以接受这种令人厌恶的东西,这与Arion的答案相似:
SELECT
c.name AS ALIAS,
ISNULL(type_name(c.system_type_id), t.name) AS DATA_TYPE,
tablecols.name AS REALNAME
FROM
sys.views v
JOIN sys.columns c ON c.object_id = v.object_id
LEFT JOIN sys.types t ON c.user_type_id = t.user_type_id
JOIN sys.sql_dependencies d ON d.object_id = v.object_id
AND c.column_id = d.referenced_minor_id
JOIN sys.columns tablecols ON d.referenced_major_id = tablecols.object_id
AND tablecols.column_id = d.referenced_minor_id
AND tablecols.column_id = c.column_id
WHERE v.name ='myView'
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这会产生:
--------------------------- |ALIAS |TYPE |REALNAME | --------------------------- |firstName |nchar|firstName | |middleName|nchar|middleName| |surName |nchar|code | |surName |nchar|lastName | ---------------------------
但是第三条记录是错误的 - 这种情况发生在使用"JOIN"子句创建的任何视图中,因为有两列具有相同的"column_id",但在不同的表中.
Ari*_*ion 12
鉴于这种观点:
CREATE VIEW viewTest
AS
SELECT
books.id,
books.author,
Books.title AS Name
FROM
Books
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我可以看到你可以获得使用的列和执行此操作所使用的表:
SELECT *
FROM INFORMATION_SCHEMA.VIEW_COLUMN_USAGE AS UsedColumns
WHERE UsedColumns.VIEW_NAME='viewTest'
SELECT *
FROM INFORMATION_SCHEMA.VIEW_TABLE_USAGE AS UsedTables
WHERE UsedTables.VIEW_NAME='viewTest'
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这适用于sql server 2005+.见这里的参考
编辑
给出相同的观点.试试这个查询:
SELECT
c.name AS columnName,
columnTypes.name as dataType,
aliases.name as alias
FROM
sys.views v
JOIN sys.sql_dependencies d
ON d.object_id = v.object_id
JOIN .sys.objects t
ON t.object_id = d.referenced_major_id
JOIN sys.columns c
ON c.object_id = d.referenced_major_id
JOIN sys.types AS columnTypes
ON c.user_type_id=columnTypes.user_type_id
AND c.column_id = d.referenced_minor_id
JOIN sys.columns AS aliases
on c.column_id=aliases.column_id
AND aliases.object_id = object_id('viewTest')
WHERE
v.name = 'viewTest';
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它为我返回:
columnName dataType alias
id int id
author varchar author
title varchar Name
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这也在sql 2005+中测试过
我花了几个小时试图找到这个问题的答案,并反复遇到不起作用的解决方案和似乎最终放弃的海报,我最终在这里偶然发现了一个似乎有效的答案:
我相信,下面的 SQL 返回的正是您正在寻找的内容,它确实满足了我的需要,并且看起来也表现良好。
SELECT name
, source_database
, source_schema
, source_table
, source_column
, system_type_name
, is_identity_column
FROM sys.dm_exec_describe_first_result_set (N'SELECT * from ViewName', null, 1)
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有关该函数的文档sys.dm_exec_describe_first_result_set
可以在此处找到,它在 SQL Server 2012 及更高版本中可用:
完全归功于链接上的海报,我自己没有解决这个问题,但我想在这里发布这个,以防它对搜索此信息的其他人有用,因为我发现这个线程比我链接到的线程容易得多。
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