FAQ: Why are other users able to see non-versioned edits that have not been committed in a SQL Server geodatabase?
Why are other users able to see non-versioned edits that have not been committed in a SQL Server geodatabase?
ArcSDE for SQL Server explicitly sets the isolation level to Read Uncommitted. This isolation level means when a user is editing, other users are able to view the changes by the editor before the editor commits or saves the changes.
It is important to understand this behavior when using non-versioned editing with ArcSDE for SQL Server, including workgroup and personal.
If a user is querying the table while it is being edited, the user who executed the query will see modifications to the data which might not be saved or committed to the database. For example, if an editor changes an attribute for several features, then realizes the changes are incorrect, any other user who reads these updated attributes would see the incorrect values. Once the editor stops editing and chooses not to save the edits, the transaction is rolled back.