LKBEN11378: Howto auto increment a field in postgres sql
LKB | Created: 02/04/2020 | Version: 0 | Language: EN | Rating: 0 | Outdated: False | Marked for deletion: False
Author: Wim Peeters - Keskon GmbH & Co. KG
Symptom
You need to create a serial to auto increment an ID in a database table
Cause
This can be used as a primary key if you need one
Solution
PostgreSQL supports a SERIAL data type. This will automatically create a sequence. e.g.:
CREATE TABLE persons (
id SERIAL,
sirname TEXT,
name TEXT
);
This will be translated into the following:
CREATE SEQUENCE persons_id_seq;
CREATE TABLE persons (
id INT4 NOT NULL DEFAULT nextval(person_id_seq),
sirname TEXT,
name TEXT
);
Automatically created sequences are named <tablename>_<serialcolumn>_seq. For more information take a look at the create_sequence manual page.
About the Author
Wim Peeters is electronics engineer with an additional master in IT and over 30 years of experience including time spent in support, development, consulting, training and database administration. Wim has worked with SQL Server since version 6.5. He has developed in C/C++, Java and C# on Windows and Linux in different European countries and different European languages. He writes knowledge base articles to solve IT problems and publishes them on the Lubby Knowledge Platform where he is one of the most important contributors and the main developer.