Can I force SQL SMO to use READ UNCOMMITTED isolation?

Question

I have an application which is using SQL2008 SMO to grab the SpaceAvailable property of all of the databases, but it often becomes blocked by other processes for long a duration. I have noted that I can run the query it generates in SSMS with no issues in READ UNCOMMITTED isolation.

So, do a way exist to force SQL SMO to use read uncommitted isolation?

Answer 1

Sorry for the late reply to this. Figured I'd post this in in case someone needs help in the future.

You can set specify the isolation level when you create your Server instance.

Make sure you have the following references:

using Microsoft.SqlServer.Management.Smo;
using Microsoft.SqlServer.ConnectionInfo; 

And then set the isolation level when creating the connection

Server theSQLServer = new Server(@"cb-z420vmsasq1\sql12");
        theSQLServer.ConnectionContext.SqlConnectionObject.BeginTransaction(System.Data.IsolationLevel.ReadUncommitted);

You may have to change this for different transactions.

Answer 2

For newer SMO versions, see https://guibubbles.wordpress.com/2017/06/05/ssms-and-smo-query-isolation/

It has to be set on the host running the app, not in the app itself.

Answer 3

Yes You can use SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED at the top of your query. Also you can change isolation level to your need. Search msdn.microsoft.com for isolation levels.