SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '374424dad9123d47c790e4901330281b9cc018947381ae3d509f0e71db375765' 
  AND token = 'oJXkPWuezwUSGRAbcEpn0Tv174SrJrpqjMQR0fEzQYM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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