Pending migrations Rails

ActiveRecord::PendingMigrationError

Quick Answer

There are unapplied migrations.

Why This Happens

In Ruby on Rails, there are unapplied migrations. This is one of the most common Ruby on Rails errors developers encounter. Understanding the root cause helps you fix it quickly and prevent it from recurring.

The Problem

# Rails shows this on startup

The Fix

rails db:migrate

Step-by-Step Fix

  1. 1

    Identify the error

    Look at the error message: ActiveRecord::PendingMigrationError. This tells you exactly what went wrong.

  2. 2

    Find the cause

    Check the stack trace to find which line of your Ruby on Rails code triggered this error.

  3. 3

    Apply the fix

    Use the corrected code pattern shown above. Test to confirm the error is resolved.

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