NEXTVAL

Retrieves the next value from a sequence.

Syntax

NEXTVAL(<sequence_name>)

Return Type

Integer.

Access control requirements

To access a sequence, the user performing the operation or the roles must have the ACCESS SEQUENCE privilege.

Examples

This example demonstrates how the NEXTVAL function works with a sequence:

CREATE SEQUENCE my_seq;

SELECT
  NEXTVAL(my_seq),
  NEXTVAL(my_seq),
  NEXTVAL(my_seq);

┌─────────────────────────────────────────────────────┐
│ nextval(my_seq) │ nextval(my_seq) │ nextval(my_seq) │
├─────────────────┼─────────────────┼─────────────────┤
│               1 │               2 │               3 │
└─────────────────────────────────────────────────────┘

This example showcases how sequences and the NEXTVAL function are employed to automatically generate and assign unique identifiers to rows in a table.

-- Create a new sequence named staff_id_seq
CREATE SEQUENCE staff_id_seq;

-- Create a new table named staff with an auto-generated staff_id
CREATE TABLE staff (
    staff_id INT DEFAULT NEXTVAL(staff_id_seq),
    name VARCHAR(50),
    department VARCHAR(50)
);

--  Insert a new staff member with an auto-generated staff_id into the staff table
INSERT INTO staff (name, department)
VALUES ('John Doe', 'HR');

-- Insert another row
INSERT INTO staff (name, department)
VALUES ('Jane Smith', 'Finance');

SELECT * FROM staff;

┌───────────────────────────────────────────────────────┐
│     staff_id    │       name       │    department    │
├─────────────────┼──────────────────┼──────────────────┤
│               3 │ Jane Smith       │ Finance          │
│               2 │ John Doe         │ HR               │
└───────────────────────────────────────────────────────┘