The Dynamic columns feature was introduced in MariaDB 5.3.
 
Syntax
------ 
COLUMN_CREATE(column_nr, value [as type], [column_nr, value
[as type]]...);
COLUMN_CREATE(column_name, value [as type], [column_name,
value [as type]]...);
 
Description
----------- 
Returns a dynamic columns blob that stores the specified
columns with values.
 
The return value is suitable for 
storing in a table
further modification with other dynamic columns functions
 
The as type part allows one to specify the value type. In
most cases,
this is redundant because MariaDB will be able to deduce the
type of the
value. Explicit type specification may be needed when the
type of the value is
not apparent. For example, a literal '2012-12-01' has a
CHAR type by
default, one will need to specify '2012-12-01' AS DATE to
have it stored as
a date. See Dynamic Columns:Datatypes for further details.
 
Examples
-------- 
-- MariaDB 5.3+:
INSERT INTO tbl SET dyncol_blob=COLUMN_CREATE(1 /*column
id*/, "value");
-- MariaDB 10.0.1+:
INSERT INTO tbl SET
dyncol_blob=COLUMN_CREATE("column_name", "value");
 

 
 
 
 
 
 
 

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