SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ac38982e1d8456334a6030f3610a857c8f535de447b83187188b2bb772e44b1' 
  AND token = 'XylK/ZNkKkqP41FqHGnCzjX4LJyNnm9++9S19S9VzGs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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