The Dynamic columns feature was introduced in MariaDB 5.3.
 
Syntax
------ 
COLUMN_DELETE(dyncol_blob, column_nr, column_nr...);
COLUMN_DELETE(dyncol_blob, column_name, column_name...);
 
Description
----------- 
Deletes a dynamic column with the specified name. Multiple
names can be given. The return value is a dynamic column
blob after the modification.
 

 
 
 
 
 
 
 

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