SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '55bb15d779247c8b643937fff1709e72ad5f342d6667587ae4eb6ef5a535b23d' 
  AND token = 'TEgEfMu8hVOCpHng0G5CsoEsPjyoQruX55Fr15bDowk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}