In-Memory Database

What Does In-Memory Database Mean?

An in-memory database (IMDB) is a database management system that primarily depends on main memory for storing computer data. IMDBs are quicker than disk-optimized databases because they carry out fewer CPU instructions, and their internal optimization algorithms are much simpler. IMDB eradicates disk access by saving and manipulating data in the main memory. An IMDB commonly includes direct data manipulation and a dedicated memory-based architecture.


IMDBs are mainly used in applications where response time is crucial, such as telecommunications network devices and mobile ad networks.

An in-memory database also may be known as a main memory database (MMDB), real-time database (RTDB) or in-memory database system (IMDS).

Techopedia Explains In-Memory Database

In-memory databases are designed to attain minimal response time, as well as extremely high throughput for performance critical systems. This is possible because data is saved and manipulated in the form used by the application, which removes overheads related to translation and caching. IMDB technology is capable of supporting application-tier deployment, real-time data management and most ACID (atomicity, consistency, isolation, durability) properties.

The data structures and algorithms of IMDBs are exclusively designed to deliver data, event and transaction management in the application tier. When compared to fully cached relational database management systems, IMDBs make use of significantly less CPU. IMDB technology does not use magnetic disks, as the location for primary database storage. Instead, the magnetic disks are used for tolerance and recovery.

The advantages of IMDBs are as follows:

  • Faster transactions
  • No translation
  • Multi-user concurrency
  • High stability

IMDB is used for:

  • Developing embedded software systems, like commercial off-the-shelf (COTS) embedded operating systems
  • Applications in medical devices, intelligent connected devices, commercial communication products and transport systems, network switches, routers and set-top boxes, etc.
  • Fulfilling the requirements of Web self service and e-commerce applications
  • Managing all real-time rating, subscriber billing and balance information

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Margaret Rouse

Margaret Rouse is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical, business audience. Over the past twenty years her explanations have appeared on TechTarget websites and she's been cited as an authority in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine and Discovery Magazine.Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages. If you have a suggestion for a new definition or how to improve a technical explanation, please email Margaret or contact her…