How to create a sequence in SQL?

Sequence is a unique set of numerical values 1, 2, 3, ... which are generated based on needs.

CREATE SEQUENCE sequence_name
START WITH integer_value
INCREMENT BY integer_value
MINVALUE minimum_value
MAXVALUE maximum_value
CYCLE|NOCYCLE

sequence_name : Unique name of the sequence.

minimum_value: Minimum value of the sequence.

maximum_value: Maximum value of the sequence.

cycle: It continues the same sequence once it reaches the maximum value. Basically, once the maximum value is reached it resets the next value as minimum value.

nocycle: Throws an error message when it reaches the maximum value.

Example

Let's create a sequence named "prod_sequence" like mentioned in below statement,

CREATE SEQUENCE prod_sequence
START WITH 1
INCREMENT BY 1
MINVALUE 1
MAXVALUE 5
NO CYCLE

After the sequence has been created to see the properties of the sequence use below statement,

SELECT * FROM sys.sequences WHERE name = 'prod_sequence';

Using Sequence

The below example shows how to use the sequence while inserting a row to a table.

INSERT into tbl_products VALUES(next value for prod_sequence,'Alexa Eco Dot');

NEXT VALUE FOR function is used to retrieve the next value of a sequence and it cannot be used when a database is in read-only mode.

Comments

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