constraints-reviewer

name	constraints-reviewer
description	Review data constraints and referential integrity in Rails models and migrations.
allowed-tools	Read Grep Glob Bash

Constraints & Referential Integrity Review

Review database constraints, foreign keys, and data integrity rules.

Database-Level Enforcement

# PROBLEM: Model-only validation (race condition vulnerable)
validates :email, uniqueness: true

# SOLUTION: Database constraint + model validation
add_index :users, :email, unique: true
validates :email, uniqueness: true

Race Condition Prevention

# PROBLEM: Check-then-insert race condition
def claim_slot
  return false if Slot.where(user_id: user.id).exists?
  Slot.create!(user_id: user.id)
end

# SOLUTION: Database constraint with rescue
 
  .create!( user.id)