BLOB column with a maximum length of
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
M bytes long.
BLOBS can also be used to store dynamic columns.
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.