SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1b44acfc72cb959b3c6ea0c7d4ecd24acd54b68dc14aba9ded768b05beb5f73' 
  AND token = 'ydzA5Xeu2WYPdSnAgd4pPODTkPQfsgXYJFMLJuoTWFA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}