BLOB

A database term.

Short for Binary Large Object.

Binary data can represent any type of data item.

The 'item' may have an internal structure that the right applications can understand. For example a photographic image in JPEG format will have a well defined structure that picture viewers can display. A sound file encoded in MP3 format can be played back using a suitable music player.

So how to store these specific binary formats in a database?

The answer is the BLOB.

The blob is a chunk of binary data that is stored in the database 'as is'. It is up to other applications to make sense of the format. The database simply stores the data in a bit-perfect manner.

The reason that items such as text and numbers are not stored as blobs is that the database offers extra features to handle these special data types. If you store a text string as a blob then all the extra features of the database are unused.

But typically, blobs are used to hold things such as image, sound files or other mulitmedia objects within a database.

2020-10