We already are using a flatbuffer with a similar scheme
namespace potter;
union Magic { Weapon, Wand }
table Weapon {
name:string;
power:int;
}
table Wand {
make:string;
animal:string;
}
table MagicHolder {
name:string;
age:int;
magic:Magic;
}
root_type MagicHolder;
Now, if we want to add two things.
level:string in the MagicHolder
Under the Wand a key:value type, where key:string, and value can be either string or int or float or bool
What I’m trying is
table MagicHolder {
name:string;
age:int;
level:string; /*new addition*/
magic:Magic;
}
table KeyValue {
key:string;
vint:int;
vfloat:float;
vbool:bool;
vstring:string;
vtype:string; /* since I cannot differentiate between bool set or not, trying to store type here */
}
table Wand {
make:string;
animal:string;
kv:KeyValue;
}
Is this the best approach? What would be the pros/cons.. Any other recommended ways to do this new additions more efficiently
Related
I am working on a shopify integration, and I am trying to perform some bulk queries which return data in jsonl format.
I read carefully the documentation, and I understood which is the principle behind this format, but there is one thing I don't understand: the following is a portion of my jsonl file representing the first item in the result
{"id":"gid:\/\/shopify\/Product\/6755349070004","options":[{"id":"gid:\/\/shopify\/ProductOption\/8677003133108","name":"Città","position":1}],"title":"Product title","productType":"Concerto Live"}
{"id":"gid:\/\/shopify\/ProductVariant\/40163436363956","price":"100.00","title":"MIlano","__parentId":"gid:\/\/shopify\/Product\/6755349070004"}
{"id":"gid:\/\/shopify\/ProductVariant\/40163436396724","price":"100.00","title":"Roma","__parentId":"gid:\/\/shopify\/Product\/6755349070004"}
{"id":"gid:\/\/shopify\/ProductVariant\/40163436429492","price":"100.00","title":"Firenze","__parentId":"gid:\/\/shopify\/Product\/6755349070004"}
{"id":"gid:\/\/shopify\/Collection\/272323707060","description":"Product variant description","title":"CONCERTI","__parentId":"gid:\/\/shopify\/Product\/6755349070004"}
{"id":"gid:\/\/shopify\/Collection\/272323739828","description":"Product variant description","title":"LIVE","__parentId":"gid:\/\/shopify\/Product\/6755349070004"}
{"id":"gid:\/\/shopify\/Collection\/273036607668","description":"Product variant description","title":"Product variant description","__parentId":"gid:\/\/shopify\/Product\/6755349070004"}
and it's obtained by the following query
mutation {
bulkOperationRunQuery(
query: """
{
items: products{
pageInfo {
hasNextPage
}
edges {
cursor
node {
id
variants(first: 10) {
edges {
node {
id
price
title
}
}
}
options(first: 5) {
id
name
position
}
title
collections(first: 8) {
edges {
node {
id
metafields(first: 5) {
edges {
node {
id
key
namespace
value
}
}
}
description
title
}
}
}
productType
images(first: 2) {
edges {
node {
src
}
}
}
}
}
}
}
"""
) {
bulkOperation {
id
status
}
userErrors {
field
message
}
}
}
So The first line it the "main" product object, the lines 2,3 and 4 are the variants, then we have the collections and then the image: the problem is that, besides the parent's id, there is no way to know which parent's property a child line refers to. If I want to build back a json from this, how can I know for example that the second line is an item of the array in products.variants?
You can use either:
the id format (gid://shopify/Product/6755349070004 is a product)
the __typename property that exists on all GraphQL objects
The issue is that I can't understand how to make a OneToOne relation between two objects the way for the first object to have a link to the second and for the second to have a link to the first. Here's the code:
[MapTo("Model")]
public class Model : CSObject<Model, int>
{
[OneToOne(LocalKey = "ModelID", ForeignKey = "ModelID")]
public Product Product { get { return (Product)GetField ("Product"); } set { SetField ("Product", value); } }
}
[MapTo("Product")]
public class Product : CSObject<Product, int>
{
[OneToOne(LocalKey = "ProductID", ForeignKey = "ProductID")]
public Model Model { get { return (Model)GetField ("Model"); } set { SetField ("Model", value); } }
}
The thing is that when I create a product and a model and set the model's property "Product" to the created one and save it, the product's "Model" property doesn't get set and remains NULL. I've already tried making all the local and foreign keys for both Product's and Model's properties the same (e.g. "ModelID") but it didn't solve the problem. What is the right way of doing this?
I guess making one of them [OneToMany] will do the trick but will return a collection while I need a single object to be returned by a property.
Update
Here comes a simple solution one would call a crutch:
[OneToMany]
public CSList<Product> _ProductList { get { return (CSList<Product>)GetField ("_ProductList"); } set { SetField ("_ProductList", value); } }
[NotMapped]
public Product Product {
get {
CSList<Product> list = this._ProductList;
if (list.Count > 0)
return list [0];
return null;
}
set {
if (value != null) {
CSList<Product> list = this._ProductList;
list.RemoveAll ();
list.Add (value);
}
}
}
You can make both relations [ManyToOne]. That will work in your scenario.
I want to figure out how payload scoring works in lucene. Since I don't understand where PayloadFunction fits in, I think I don't really understand how it works. Tried googling for it, but couldn't find much apart from advice to go through source. Well, it would be nice if someone can explain it here, else source code it is :)
There are three parts of it. First of all you should generate payloads during analysis. This could be done using PayloadAttribute. You just need to add this attribute to terms you want during analysis.
class MyFilter extends TokenFilter {
private PayloadAttribute attr;
public MyFilter() {
attr = addAttribute(PayloadAttribute.class);
}
public final boolean incrementToken() throws IOException {
if (input.incrementToken()) {
Payload p = new Payload(PayloadHelper.encodeFloat(42));
attr.setPayload(p);
} else {
attr.setPayload(null);
}
}
Then during searching you should use special query class PayloadTermQuery. This class behaves as SpanTermQuery but do track of payloads in index. Using custom Similarity implementation you could score each payload occurrence in document.
public class MySimilarity extends DefaultSimilarity {
public float scorePayload(int docID, String fieldName,
int start, int end, byte[] payload,
int offset, int length) {
if (payload != null) {
return PayloadHelper.decodeFloat(payload, offset);
} else {
return 1.0f;
}
}
}
Finally, using PayloadFunction you could aggregate payload scores over document to produce final document score.
I am a bit lot about what to do in an OO/DB relation...
Here is the DB model :
CREATE TABLE User
Id
CREATE TABLE Location
userId
// EDIT oups, wrong !
// placeId
// Should be :
seatId
CREATE TABLE Game
locationId
Now some code :
class User
{
private Location locations[]; // need this for several reasons...
public function loadFromDatabase()
{
// Load data from DB
// ...
result = DB::query("SELECT Id FROM Locations WHERE userId="+this->Id);
foreach(result)
{
l = new Location();
l->loadFromDatabase(result);
locations[] = l;
}
}
}
class Location
{
private User user;
public function loadFromDatabase()
{
...
}
}
class Game
{
private Location location;
public loadFromDatabase()
{
/*
Here comes the problem :
how to have a reference to a location
created by the User class ?
*/
}
}
A User play Games in several Locations.
EDIT : And for each location the user plays on seat. Or on another seat...
When I want to know where a game has been played I access Game.location. And when I want to know who played it, I access Game.location.user
Here is my problem : I want the Game.location to be the same reference to one of the User.locations and I do not know how to do this...
And, globally, I feel something wrong about my code...
Any help ?
Thanks
Since you have a placeId in your Location table, I assume there is a Place table which describes what the places actually are, while the Location table simply represents the many-to-many mapping between users and places.
In that case, Location doesn't need to have an Id of its own and doesn't need to be a class, but Place does.
To load just one instance of each object from the database, cache the instances in a static map inside each class.
class Place
{
// Static
private static Place loadedPlaces[];
public static function get(id)
{
if (!loadedPlaces[id])
{
loadedPlaces[id] = new Place(id);
loadedPlaces[id]->loadFromDatabase();
}
return loadedPlaces[id];
}
// Non-static
private id;
public function loadFromDatabase()
{
// ...
}
}
Then to get references to places for the properties of a user or a game, you just access them via the static method.
class User
{
public function loadFromDatabase()
{
result = DB::query("SELECT placeId FROM Locations WHERE userId="+this->Id);
foreach(result)
{
places[] = Place::get(result);
}
}
}
class Game
{
public function loadFromDatabase()
{
place = Place::get(place);
}
}
This uses:
Lazy initialization, because places are only loaded when they are needed.
Multiton pattern, because there is only one instance of each place by id.
Not quite a factory method, because there's no object hierarchy involved.
I have got four tables in NHibernate
Job
{
DBID { int, primary key }
Name { string }
Media { fk_media (int) }
PublishInfo { fk_publishinfo (int) }
}
Media
{
DBID { int, primary key }
TransmissionID { string }
Series { string }
Title { string }
Description { string }
}
PublishInfo
{
DBID { int, primary key }
Destination { string }
AudioTrack_1 { fk_audiolanguage }
AudioTrack_2 { fk_audiolanguage }
AudioTrack_3 { fk_audiolanguage }
AudioTrack_4 { fk_audiolanguage }
}
AudioLanguage
{
Code { string, primary key }
Description { string }
}
What I want to achive with NHibernate is that it only stores unique records. So if a Media is used multiple times they all point to the same media entry. Same goes for PublishInfo.
A second issue I ran into is that when using the same audiolanguage for audiotrack_3 and 4 for instance it gives a error that is was already used in the session.
Any tips how I would do this properly?
This is a partial anwser to my own question. The reason it wasn't working correctly for the languages when using same lanuage on multiple tracks is because they got send back and forth between a client and server application. The way I solved this is by receiving it back to the server I lookup the proper objects stored in a list on the server and replace them.
I do not think this is the proper solution but it works.