SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2e2592bfa7a494f94b46393031d5931766b8106f2219a9137e6726b2ff589039' 
  AND token = '6NsLvMs5buiBO/q/XFtAD3qSS88ZUpDUxGc4xwJODz8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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