SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9390d7c8cbd12899faae21d254bd6b1de9b5caf61c537d402d59200f5c008d48' 
  AND token = 'WIvvuFepUPVFOJaX0ELeW0HftNHLpG+9/35Lrk/7Ta0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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