SQL Server Isolation Levels

Pamela M. takes us through a humorous journey covering transaction isolation levels in SQL Server:

READ COMMITTED:  One step up (and the default for SQL Server).    A query in the current transaction can’t read data modified by someone else that hasn’t yet committed.  No dirty reads.  BUT….data could be changed by others between statements in the current transaction, so the data may not look the same twice.  READ COMMITTED uses shared locks to prevent dirty reads, but that’s about all you get.  You still get non-repeatable reads and phantom reads here (more on phantom reads below).

Click through for the full list.

Related Posts

Dealing with a Massive Transaction Log File

Kevin Hill takes us through troubleshooting an oversized transaction log file: I had a customer call in this week after struggling to resolve an issue for a couple of days,  Their Transaction Log file had grown to 400+GB and was filling the drive to the point that had to keep adding space to the drive […]

Read More

Distributed Transactions on Linux

Tejas Shah and crew announce distributed transactions with SQL Server on Linux: With SQL Server 2017, a new era was heralded with SQL server being available to deploy on Linux (and Linux based container) systems. While all functionality of the SQL Server engine were brought over as is to SQL Server on Linux, some of […]

Read More

Categories

April 2019
MTWTFSS
« Mar May »
1234567
891011121314
15161718192021
22232425262728
2930