SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3fbadf0ddfa5203270de30cdcc827992249ea6d6b0a1410aa51fdff822f1ba4e' 
  AND token = '5Q/aIU25VIw+xqcjAAolJl+AsJAPpbQPUXiMIDOZUgE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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