SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '18994f4c479f09529a083d3b35e5a2b135e250c05b1c33438724c53effc389d1' 
  AND token = 'Llu/546SKOPaF7hJlOIuFknj5ZqBtqOZAyf2095/Bfc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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