Example:
USE AnotherDB
-- This works - same ID as from other DB
SELECT OBJECT_ID('AnotherDB.ASchema.ATable')
-- This works
SELECT OBJECT_NAME(OBJECT_ID('AnotherDB.ASchema.ATable'))
USE ThisDB
-- This works - same ID as from other DB
SELECT OBJECT_ID('AnotherDB.ASchema.ATable')
-- Gives NULL
SELECT OBJECT_NAME(OBJECT_ID('AnotherDB.ASchema.ATable'))
Obviously the metadata functions expect a current database. The BOL entries typically have language like this for functions like OBJECT_NAME
etc.:
The Microsoft SQL Server 2005 Database Engine assumes that object_id is in the context of the current database. A query that references an object_id in another database returns NULL or incorrect results.
The reasons I need to be able to do this:
I can't USE the other database from within an SP
I can't create a proxy UDF stub (or alter anything) in the other databases or in master (or any other database besides my own) to help me out.
So how can I get the database from OBJECT_ID('AnotherDB.ASchema.ATable')
when I'm in T开发者_如何学编程hisDB?
My goal is to take a possibly partially qualified name from a configuration table, resolving it in the current context to a fully qualified name, use PARSENAME to get the database name and then dynamic SQL to build a script to be able to get to the meta data tables directly with database.sys.*
or USE db; sys.*
You should be able to do this:
SELECT
name
FROM
AnotherDB.sys.objects --changes context
WHERE
object_id = OBJECT_ID('AnotherDB.ASchema.ATable')
This is what you effectively do with OBJECT_ID('AnotherDB.ASchema.ATable')
This means that you could rely on dbname.sys.objects and avoid confusion with metadata functions.
Note: the new Catalog views are designed to be used and not change from version to version, as per the link. In the old days, it was consider bad practice to use system tables but the stigma still remains. So, you can safely rely on sys.objects rather that the metadata functions.
Do I understand it correctly that you want the db id of AnotherDB?
SELECT *
FROM master..sysdatabases
WHERE name = 'AnotherDB'
Otherwise, you can USE other db's in dynamic SQL if it helps:
DECLARE @SQL NVARCHAR(MAX)
, @objId INT
SET @SQL = N'
USE AnotherDB
SELECT @id = OBJECT_ID(''customer'')
'
EXEC SP_EXECUTESQL @SQL
, N'@id INT OUTPUT'
, @id = @objId OUTPUT
SELECT @objId
OR Execute SP's in other dbs with:
EXEC AnotherDB.dbo.ProcedureName
@paramX = ...
, @paramY = ...
Take a look at the PARSENAME function in TSQL - will allow you to pull out any of the 4-part portions of a fully (or non-fully) qualified name. For the database in your example:
select parsename('AnotherDB.ASchema.ATable',3)
returns:
AnotherDB
select parsename('AnotherDB.ASchema.ATable',2)
returns:
ASchema
If non-fully qualified, you'll get null results if you ask for the portion of a name that isn't included in the string:
select parsename('ASchema.ATable',3)
returns:
NULL
I had the same issue but with OJBECT_SCHEMA_NAME as well. Following on from chadhoc's response using parsename works with OBJECT_NAME like:
DECLARE @OrigTableName NVARCHAR(MAX);
SELECT @OrigTableName = 'AnotherDB.ASchema.ATable'
SELECT OBJECT_NAME(OBJECT_ID(@OrigTableName), DB_ID(PARSENAME(@OrigTableName, 3)))
, OBJECT_SCHEMA_NAME(OBJECT_ID(@OrigTableName), DB_ID(PARSENAME(@OrigTableName, 3)))
I used the following solution:
DECLARE @SchemaName varchar(255) = 'SchemaName'
DECLARE @ObjectName varchar(255) = 'ObjectName'
SELECT o.*
FROM AnotherDB.sys.objects AS o
INNER JOIN AnotherDB.sys.schemas AS s ON o.schema_id = s.schema_id
WHERE s.name = @SchemaName
AND o.name = @ObjectName
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