In today’s digital world, companies are collecting, storing and analyzing data more than ever before in human history. The data within a database needs to be managed effectively in order for it to provide optimal value to the company. Database Manage Systems helps the data management process.
Fundamentally, a transaction is just a group of tasks which represents the minimum processing unit. To put multiple transactions together, there are problems that can arise because of concurrency. The transaction throughput is just the number of transactions that can be performed in a given time period.
Concurrency control is then the process of managing simultaneous execution of transactions in a shared database. The purpose of concurrency control is to enforce isolation, preserve database consistency and to resolve read-write and write-write conflicts. Concurrency control is important to ensure atomicity, isolation, and serializability of concurrent transactions.
If it is insisted that only one transaction can execute at a time (that is, in serial order), then performance can be poor. At the highest level, concurrency control is a method for scheduling or controlling the operations of transactions in such a way that they can be executed safety. For transactions to be executed safely, they need to not cause the database to reach an inconsistent state.
For the conservative concurrency control, the pros include that all transactions can be executed correctly, the data is properly consistent and the database is relatively stable and reliable. The cons include that transactions can be slow, run time can be longer and throughput can be decreased.
For optimistic concurrency control, the strengths include transactions that are executed efficiently, relatively safe data content and potentially higher throughput. The cons include the risk of data inference, that there could be hidden errors, and that transactions could deadlock.
If concurrency is controlled properly, then it is possible to maximize transaction throughput while avoiding the change of corrupting the database.
A company’s performance can be dependent on how effectively the data is managed. Understanding these components help companies have effective Database Manage Systems.