A BLOB column with a maximum length of 65,535 (216 - 1) bytes. Each BLOB value is stored using a two-byte length prefix that indicates the number of bytes in the value.

An optional length M can be given for this type. If this is done, MariaDB creates the column as the smallest BLOB type large enough to hold values M bytes long.

BLOBS can also be used to store dynamic columns.

Before MariaDB 10.2.1, BLOB and TEXT columns could not be assigned a DEFAULT value. This restriction was lifted in MariaDB 10.2.1.


In MariaDB 10.4, it is possible to set a Unique index on a column that uses the BLOB data type. In previous releases this was not possible, as the index would only guarantee the uniqueness of a fixed number of characters.

Oracle Mode

MariaDB starting with 10.3

In Oracle mode from MariaDB 10.3, BLOB is a synonym for LONGBLOB.

See Also

Content reproduced on this site is the property of its respective owners, and this content is not reviewed in advance by MariaDB. The views, information and opinions expressed by this content do not necessarily represent those of MariaDB or any other party.

© 2019 MariaDB
Licensed under the Creative Commons Attribution 3.0 Unported License and the GNU Free Documentation License.