step size cannot equal zero

Symptoms

A generate_series() call was given a step of zero. A zero step would never reach the end value, so PostgreSQL raises SQLSTATE 22023 (invalid_parameter_value).

• The step argument to generate_series is 0.
• A zero step would loop forever.
• Common with a computed step that can be zero.

What the server log shows

ERROR:  step size cannot equal zero

Why PostgreSQL raises this — what the manual says

Section 9.25 Set Returning Functions:

“Generates a series of values from start to stop, with a step size of step.”

generate_series advances by step on each iteration. A zero step never progresses toward stop, which would be an infinite series, so PostgreSQL rejects it with 22023.

Common causes

• A literal step of 0.
• A computed step expression evaluating to 0.
• Variable step values not guarded against zero.

How to fix it

1. Use a nonzero step (positive or negative as needed).
2. Guard computed steps so they are never zero.
3. Handle the single-value case separately when step would be zero.

Related & next steps

• SQLSTATE 22023 — Invalid Parameter Value (full reference)
• Message: division by zero
• Glossary: generate_series

Reference: PostgreSQL 18 Section 9.25 “Set Returning Functions”.