Can anyone share his/her notes regarding DBMS


Please can one share notes to DBMS, mainly for Transactions and concurrency control ?


Transaction Management

A sequence of many actions which are considered to be one atomic unit of work. A transaction is a collection of operations involving data items in a database. There are four important properties of transactions that a DBMS must ensure to maintain data in the face concurrent access and system failures.


Concurrency Control: Process of managing simultaneous execution of transactions in a shared database, is known as concurrency control. Basically, concurrency control ensures that correct results for concurrent operations are generated, while getting those results as quickly as possible.
Need of Concurrency Control: Simultaneous execution of transactions over a shared database can create several data integrity and consistency problems.


you can refer to link below to get notes on transactions and concurrency control