http://social.msdn.microsoft.com/Forums/en-US/sqldatabaseengine/thread/478aa50f-b7dd-43fb-bb90-813057a6a1ed/

–2
UPDATE authors
SET au_lname = ‘X’
WHERE au_id = ’238-95-7766′

–3
SET TRANSACTION ISOLATION LEVEL SERIALIZABLE
BEGIN TRAN
SELECT * FROM authors

–4
SET TRANSACTION ISOLATION LEVEL SERIALIZABLE
BEGIN TRAN
SELECT * FROM authors

–5
EXEC sp_who2

You will see that 2 is blocked by 1, 3 is blocked by 2 and 4 is blocked by 3. Theoretically, 3 and 4 could execute (there’s only a shared lock), but queuing makes 3 and 4 to wait. This is how livelocks are avoided: queuing.

Awesome explanation…..

Can you please provide a live senario example with select statements and some update statements.

sql session1: where i am inserting the table

begin Tran T1
insert into test values(16,’xyz’)
waitfor delay ’00:00:30′
commit tran t1

sql session2:where i am selecting the data from a table

select * from test

the first session is taking 30 seconds, at the same time if i fired a query on the same table(test) it gives the result while the first session gets completed, so
why begin Trans is locking the whole table instead of row lock, Please give me the idea..

e.g,

dbcc inputbuffer()

through this we generally can’t get the entire operation string which is working. how to retrieve the entire command working?

Gud explanation abt live lock. But if you can tell us how to avoid Live lock or is there a way to find it and resolve it? If you have a scrip or something if you can share with us.

Thanks