SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97580fcb7b84c6cccac21717eaf31331d5051d09952b69c9bde4442cf8cd42af' 
  AND token = 'bB2H3fzBnaMVItY3o8GrGolVyuxr7HYAgy4qjKsv5is=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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