Resources / PostgreSQL Tutorial

SERIAL Data Type

SERIAL Data Type explained with practical SQL patterns, edge cases, and production-ready guidance.

10 min read

Spin up a Postgres database in 20 seconds with Vela.

Try Vela Sandbox

SERIAL Data Type in PostgreSQL Data Types helps you write SQL that is easier to test, review, and operate at scale.

Introduction to SERIAL Data Type

Use SERIAL Data Type to model application data accurately and avoid implicit-cast surprises.

Commonly paired with: SELECT, FROM, WITH, INSERT.

Practical examples with SERIAL Data Type in PostgreSQL

Reference pattern: start from canonical syntax and keep it explicit.

CREATE TABLE typed_values (
  id BIGSERIAL PRIMARY KEY,
  value SERIAL NOT NULL
);

Production-style scenario: apply the same concept to realistic application data.

SELECT
  o.order_id,
  o.total_amount,
  o.placed_at
FROM orders o
WHERE o.placed_at >= now() - interval '30 days'
ORDER BY o.placed_at DESC
LIMIT 50;

Additional example: use a variation to validate behavior and edge cases.

CREATE TABLE sensor_readings (
  reading_id BIGSERIAL PRIMARY KEY,
  payload JSONB NOT NULL,
  recorded_at TIMESTAMPTZ NOT NULL DEFAULT now()
);

Production tips

  • Prefer explicit column lists and deterministic ordering when results feed APIs or batch jobs.
  • Validate plans with EXPLAIN before adding indexes, then re-check after schema changes.
  • Keep DDL, data backfills, and cleanups in transactions when possible to avoid partial state.
  • Use isolated environments for risky changes so query tuning and schema experiments stay safe.

Vela workflow tip

Test this pattern in an isolated branch database, share the result with your team, and promote only after query plans and row counts look correct.

Reference: PostgreSQL official documentation.

Continue through the next items in PostgreSQL Data Types: DATE .

Related: Boolean CHAR, VARCHAR, and TEXT NUMERIC