[
  {
    "type": "alter_table",
    "description": "Add retry_count column to chat_messages for tracking SMS retry attempts (max 2 retries)",
    "database": "{{store}}",
    "check_query": "SELECT COLUMN_NAME FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = 'chat_messages' AND COLUMN_NAME = 'retry_count' LIMIT 1",
    "sql": "ALTER TABLE `chat_messages` ADD COLUMN `retry_count` TINYINT UNSIGNED NOT NULL DEFAULT 0 AFTER `delivery_error`"
  }
]