[
  {
    "type": "raw_sql",
    "description": "Add index on billingSmsUsage.providerMessageId — sms:cost-lookup and delivery status webhooks do WHERE providerMessageId = ? lookups without an index, triggering full table scans (~662K rows, ~20s each). Adding a non-unique index (4-5 duplicate providerMessageIds exist from webhook retries) makes these O(log N).",
    "database": "kiosk_buykiosk",
    "check_query": "SELECT 1 FROM INFORMATION_SCHEMA.STATISTICS WHERE TABLE_SCHEMA = 'kiosk_buykiosk' AND TABLE_NAME = 'billingSmsUsage' AND INDEX_NAME = 'idx_provider_message_id' LIMIT 1",
    "sql": "ALTER TABLE `billingSmsUsage` ADD INDEX `idx_provider_message_id` (`providerMessageId`)"
  }
]