SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eb82cc2eb6536fb157195a6123f132cb1786be692bc617def3eb0be93aad4a84' 
  AND token = 'EYX/MRxWXLKdvH+RcwHVhUfY2H3Jmttlh36B9wyxy6g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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