SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6765afe148ff01b89f3298734fca96bb8b58268538384ef65f8c806ab4dcaf49' 
  AND token = 'G9AgOxzCKArnIzXRMoMR6KdKbckWPA9ZZu+weudaHsc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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