SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '44d3d64d9fa05b36968204dc421cdae636cbf55570cd8870625822913e2ce349' 
  AND token = 'BQ5lBgzXmo4liD/Ya539wGzztxddBjclQnSM+K3hOQs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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