SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6ccdb30e33e6eecfe03efd3bf733f3072f72acdf2bd4bb1f75867bfa0656f358' 
  AND token = 'Npzd40LngVyPBM7hQNiM/Uo9vduoGZ5y+cxGyBdrT0g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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