Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '39ad7645688c2dee17bffcee31176f70c593b470ee45cf14ca08663538623147' 
  AND token = '/+rOBRhnAH9/GrtXDya1NrVPrEW2bWG7RPUrMsWNWFg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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