Accessing changes in Database while Transaction is Running

Question

I'm developing a .NET application that interacts with a database. In a method I begin a SQL Transaction and modify some values in table1, after I'm done with the changes (but still haven't committed the transaction) I launch a Threading.Thread to go update values in table2 using data from table1.

Will this thread read the modified values? Or will it load the data as it was before transaction was begun?

Joel B Fant · Accepted Answer · 2011-03-17 18:42:43Z

2

It depends on if the second thread is using the same connection/session in which the transaction was started. If it is, then it can see the changes made so far during that transaction. If it is a different connection, it will be blind to those changes until they are committed.

answered Mar 17, 2011 at 18:42

Joel B Fant

24.8k4 gold badges70 silver badges68 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

PedroC88 · Accepted Answer · 2011-03-17 22:18:13Z

2

Using the RepeatableRead or ReadUncommitted transaction isolation levels for the transaction in the second thread will allow you to read the uncommitted data from table1.

More info on transaction isolation levels:

IsolationLevel Enumeration

Set Transaction Isolation Level (Transact-SQL)

Different is the question how will you ensure that the data is written to table1 before reading it and updating table2, but this depends on your .NET application implementation.

edited Mar 17, 2011 at 22:18

PedroC88

3,8688 gold badges49 silver badges86 bronze badges

answered Mar 17, 2011 at 21:21

Iliyan

813 bronze badges

Collectives™ on Stack Overflow

Accessing changes in Database while Transaction is Running

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related