When building software you should understand what level of transaction isolation your RDBMS guarantees. Do you? I meen, how much of the “I” in the ACID we have? Here are the default transaction isolation levels in a popular relational database management systems:
|RDBMS||Default transaction isolation level|
|ANSI SQL Standard||Serializable|
|MS SQL Server||Read Committed|
If you are unsure what that means, Wikipedia has a nice explaination.