[
  {
    "type": "alter_table",
    "description": "Make lastModifiedBy nullable in daybook_whiteboard_canvas (canvas drawings are anonymous)",
    "database": "{{store}}",
    "check_query": "SELECT IS_NULLABLE FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = 'daybook_whiteboard_canvas' AND COLUMN_NAME = 'lastModifiedBy' AND IS_NULLABLE = 'YES'",
    "sql": "ALTER TABLE `daybook_whiteboard_canvas` MODIFY `lastModifiedBy` INT(10) UNSIGNED NULL COMMENT 'Employee ID who last modified (NULL for anonymous)'"
  }
]