Book Image

MariaDB Cookbook

By : Daniel Bartholomew
Book Image

MariaDB Cookbook

By: Daniel Bartholomew

Overview of this book

Table of Contents (20 chapters)
MariaDB Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Creating tables with dynamic columns


Tables with dynamic columns are similar to regular tables, but not quite the same. Similar to standard tables, they have columns and rows. The difference is that each row can have a different number of columns holding the data and the data types that are appropriate for that row.

How to do it...

  1. Launch the mysql command-line client and connect to our MariaDB server.

  2. Create a test database and use it with the following command:

    CREATE DATABASE IF NOT EXISTS test;
    USE test;
    
  3. Create a table with a standard PRIMARY KEY column and a BLOB column using the following commands:

    CREATE TABLE dyn_example (
      id SERIAL PRIMARY KEY,
      dyn_cols BLOB
    );
    

How it works...

The dynamic columns feature in MariaDB is a set of special functions that allow us to define and redefine the number of columns and their data types as needed on a row-by-row basis without altering our table configuration. These special columns exist and are defined as a standard BLOB column in our CREATE...