Importance Of ObjectId

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Importance Of ObjectId

Shadab Shah

SSCarpal Tunnel

Points: 4759
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August 1, 2012 at 12:22 am

#264414

I have search this topic on internet. But the way of explanation has being too far of expert level. I would like to know the importance of objectid. I have quite often seen this thing being used in queries related to fetching some system related data. I would like to know
1.What is importance of objectid
2.What is objectid
3.Why should we used objectid.

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Gail Shaw SSC Guru Points: 1004504 More actions · Answer 1

It's just an identifier value that's used throughout the system tables. Much like you might create a product table with a productID column and use the productID in related tables.

Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

We walk in the dark places no others will enter
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Orlando Colamatteo SSC Guru Points: 182276 More actions · Answer 2

sys.objects - SQL Server 2008 R2

object_id is a column in the sys.objects catalog view and uniquely identifies an object in the current database. In other words the object_id for a table named dbo.MyTable in Database1 will be different than the object_id for a table named dbo.MyOtherTable in Database1. Similarly, the object_id for dbo.MyTable in Database1 will likely be different than the object_id for a table with the same name in a different database since the pool of object_id's is managed at the database level.

sys.objects holds references to many different types of database objects. In the link I posted look for the column type_desc.

There are other catalog views that describe particular types of objects more specifically than the information you can find in sys.objects. For example run this in your database:

SELECT * FROM sys.tables;

This describes tables much more deeply than sys.objects.

Then pick one of the object_id values and run this:

SELECT * FROM sys.objects WHERE object_id = the_id_picked_from_sys.tables;

There are many other catalog views that make sue of object_id. sys.objects is the main view. Here is a data map in case you want to do a deep dive on catalog views. Loko for the 'Objects' section in the top left: SQL Server 2008 System Views Map

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