In plain English, what are the disadvantages and advantages of using
SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED
in a query for .NET applications and reporting services applications?
isolation-levelsql servertsql
In plain English, what are the disadvantages and advantages of using
SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED
in a query for .NET applications and reporting services applications?
Best Answer
This isolation level allows dirty reads. One transaction may see uncommitted changes made by some other transaction.
To maintain the highest level of isolation, a DBMS usually acquires locks on data, which may result in a loss of concurrency and a high locking overhead. This isolation level relaxes this property.
You may want to check out the Wikipedia article on
READ UNCOMMITTED
for a few examples and further reading.You may also be interested in checking out Jeff Atwood's blog article on how he and his team tackled a deadlock issue in the early days of Stack Overflow. According to Jeff:
One alternative to the
READ UNCOMMITTED
level that you may want to consider is theREAD COMMITTED SNAPSHOT
. Quoting Jeff again: