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MariaDB : Sequences (AUTO_INCREMENT)

Tutorial by:      Date: 2016-04-18 05:50:32

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This MariaDB tutorial explains how to create sequences using the AUTO_INCREMENT attribute in MariaDB with syntax and examples.


In MariaDB, you can create a column that contains a sequence of numbers (1, 2, 3, and so on) by using the AUTO_INCREMENT attribute. The AUTO_INCREMENT attribute is used when you need to create a unique number to act as a primary key in a table.


The syntax to create a sequence (or use the AUTO_INCREMENT attribute) in MariaDB is:

CREATE TABLE table_name


  column1 datatype NOT NULL AUTO_INCREMENT,

  column2 datatype [ NULL | NOT NULL ],




The attribute to use when you want MariaDB to assign a sequence of numbers automatically to a field (in essence, creating an autonumber field).


Each column should be defined as NULL or NOT NULL. If this parameter is omitted, the database assumes NULL as the default.


  • You can use the LAST_INSERT_ID function to find last value assigned by the AUTO_INCREMENT field.


Let's look at an example of how to use a sequence or the AUTO_INCREMENT attribute in MariaDB.

For example:



  site_name VARCHAR(30) NOT NULL,

  host_name VARCHAR(40),

  creation_date DATE,

  CONSTRAINT sites_pk PRIMARY KEY (site_id)


This MariaDB AUTO_INCREMENT example creates a table called sites which has 4 columns and one primary key:

  • The first column is called site_id which is created as an INT datatype (maximum 11 digits in length) and can not contain NULL values. It is set as an AUTO_INCREMENT field which means that it is an autonumber field (starting at 1, and incrementing by 1, unless otherwise specified.)
  • The second column is called site_name which is a VARCHAR datatype (maximum 30 characters in length) and can not contain NULL values.
  • The third column is called host_name which is a VARCHAR datatype (maximum 40 characters in length) and can contain NULL values.
  • The fourth column is called creation_date which is a DATE datatype and can contain NULL values.
  • The primary key is called sites_pk and is set to the site_id column.

Set AUTO_INCREMENT starting value

Now that you've created a table using the AUTO_INCREMENT attribute, how can you change the starting value for the AUTO_INCREMENT field if you don't want to start at 1?

You can use the ALTER TABLE statement to change or set the next value assigned by the AUTO_INCREMENT.


In MariaDB, the syntax to change the starting value for an AUTO_INCREMENT column using the ALTER TABLE statement is:

ALTER TABLE table_name AUTO_INCREMENT = start_value;


The name of the table whose AUTO_INCREMENT value you wish to change. Since a table in MariaDB can only contain one AUTO_INCREMENT column, you are only required to specify the table name that contains the sequence. You do not need to specify the name of the column that contains the AUTO_INCREMENT value.


The next value in the sequence to assign in the AUTO_INCREMENT column.


Let's look at an example of how to change the starting value for the AUTO_INCREMENT column in a table in MariaDB.

For example:


This MariaDB AUTO_INCREMENT example would change the next value in the AUTO_INCREMENT field (ie: next value in the sequence) to 1000 for the site_id field in the sites table.


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