Syntax
------ 
LONGBLOB
 
Description
----------- 
A BLOB column with a 
maximum length of 4,294,967,295 bytes or 4GB (232 - 1). The
effective maximum length of LONGBLOB columns depends on the
configured maximum packet size in the client/server protocol
and
available memory. Each LONGBLOB value is stored using a
four-byte
length prefix that indicates the number of bytes in the
value.
 
Oracle Mode
 
In Oracle mode from MariaDB 10.3, BLOB is a synonym for
LONGBLOB.
 


URL: https://mariadb.com/kb/en/longblob/