Someone knows what model is this? [on hold]

I saw a dictionary app on the Play Store. Different people have used the same application for their projects. here are some examples

https://play.google.com/store/apps/details?id=com.dictionary.psychologymb&hl=tr

https://play.google.com/store/apps/details?id=com.alifinnovative.SynonymAntonymsDictionary&hl=tr

https://play.google.com/store/apps/details?id=com.zhystudio.MedicalAbbreviationsDictionary&hl=tr

https://play.google.com/store/apps/details?id=com.offlinedictionary.law&hl=tr

https://play.google.com/store/apps/details?id=com.dictionary.arjunastudiomedicine&hl=tr

etc … there are many other applications of users. After some research, I found this github page. I think it's here that everything starts

https://github.com/blinskey/greek-reference

But this repository is too old. And apps on Google Play are slightly modified. So I think there may be another free or paid version on the Internet. Everyone knows where can I find this app on the internet except github?

c # – Is this model of constructor "good" or does it have fatal flaws?

Sorry there is a "code revision" equivalent to this StackExchange … but for a specific question: is there a flagrant flaw in the following implementation of a Builder template?

Background: I am just beginning to understand the idea of ​​separating the domain model from the persistence layer (by Uncle Bob), service layer / IoC / separation of concerns / injection of dependency, by examining some aspects of DDD (possibly aggregates?). ), apply invariants (for example, have all the private setters below) … And I'm trying to find patterns that help to achieve those goals – ones that the rest of the team can follow and adapt … I do multiple jumps in comprehension and I do not want to twist my ankle when I'm landing.

One result of my efforts is this builder model for large objects (many fields), which implements a fluid API and tries to allow subclassification (CE required generic gymnastics). My idea is that a subclass of the domain model object becomes an EF core entity with properties and methods specific to persistence in the subclass, but that essential business logic can always exist (and be tested) on the main domain model objects.

Some notes:

  • Classes and business logic are clearly incomplete.
  • Nested classes are used because they allow the generator to access private / protected members.
  • Suppose that Id is a store – specific property and is not necessary for other use cases.
  • the Builder property on the Event object is primarily intended to be syntactic sugar to allow customers to say Event.Builder instead of new Event.EventBuilder().
  • And if anyone asks, I will not wrap any EF Core into a repository model / UoW (for now, I buy the arguments that DbContext is a UoW and DbSet is a repository) … although I put a repository wrapper around some particular entities (such as audit events) that I would like to implement with a different type of store.

So, here is a base Event class, a domain model class with an interior EventBuilder class:

using System;
using System.Collections.Generic;

namespace App.Core
{
    public class Event
    {
        public String Title { get; private set; }
        public DateTimeOffset Start { get; private set; }
        public DateTimeOffset End { get; private set; }
        // Lots more properties omitted here...
        protected Event() { }

        public static EventBuilder Builder => new Event.EventBuilder();
        public class EventBuilder where T : Event
        {
            protected virtual T Result { get; set; } = Activator.CreateInstance(typeof(T), true) as T;
            public EventBuilder WithTitle(String title)
            {
                Result.Title = title;
                return this;
            }

            public EventBuilder WithStartAndEnd(DateTimeOffset start, DateTimeOffset end)
            {
                if (start == null)
                {
                    throw new ArgumentNullException(nameof(start));
                }
                if (end == null)
                {
                    throw new ArgumentNullException(nameof(start));
                }
                if (end < start)
                {
                    throw new ArgumentOutOfRangeException(nameof(end), end, "End date must be on or after the start date.");
                }
                this.Result.Start = start;
                this.Result.End = end;
                return this;
            }
            public virtual T Create()
            {
                // Last chance validation here!
                return this.Result; 
            }
        }
    }
}

And here is a subclass with features specific to persistence:

namespace App.Repository.Entities
{
    public class Event : App.Core.Event
    {
        public int Id { get; private set; }

        public new static EventBuilder Builder => new Event.EventBuilder();

        public new class EventBuilder : App.Core.Event.EventBuilder where T : Event
        {
            //protected new T _result = Activator.CreateInstance();
            //protected new T _result = Activator.CreateInstance(typeof(T), true) as T;
            public EventBuilder WithId(int id)
            {
                this.Result.Id = id;
                return this;
            }

            public override T Create()
            {
                // Last chance validation for subclass here!
                // This is safe because we know it's operating on a subclass this.Result:
                var result = base.Create() as T;
                return result;
            }
        }
    }
}

And here is a naïve client code that uses the subclass:

using System;
using System.Collections.Generic;
using Microsoft.AspNetCore.Mvc;
using App.Repository.Entities; // <-- Note this namespace

namespace App.Web.Controllers
{
    (Route("api/(controller)"))
    (ApiController)
    public class EventsController : ControllerBase
    {
        // GET: api/Event
        (HttpGet)
        public ActionResult> Get()
        {
            return new Event() {
                Repository.Entities.Event.Builder
                    .WithId(5126)
                    .WithTitle("The Apocalypse")
                    .WithStartAndEnd(
                        new DateTimeOffset(2012, 12, 21, 6, 12, 0, new TimeSpan(-4,0,0)), 
                        new DateTimeOffset(2012, 12, 21, 6, 12, 1, new TimeSpan(-4,0,0))
                        )
                    .Create()
            };
        }
        // Other REST methods omitted...
    }
}

So, do you see anything very stupid about the above going to fry me when I try to use the approach? The above is certainly a little naive and I would appreciate other comments / suggestions, but a good answer will highlight a defect that will make me want to radically change the design or reject it completely.

Neural Networks – The Deep Learning Model Outperforms Explicit Batch Sizes

I have created a thorough learning model for time series forecasting. The model works very well. I've tried different batch sizes 32, 50, 64, 100, 128 and 256.
I've got the best result for a batch size of 50. With a batch size of 32, the model still works, but the convergence of the error takes too much time.
I've tried several experiments with a batch size of 64. With this lot size, the model is not able to learn. The MAE is very high, the learning error decreases, but the validation error is very high. It seems that the model is too heavy for a lot size of 64.
I have therefore done other experiments with a batch size of 100, 128 and 256.
100 works of, but not as good as 50. 128 shows the same results as 64. 256 shows good results in training and validation error, but not in the MAE.
Do you have any ideas for which 64 and 128 do not work?
I know that models tend to over-adjust, when the lot size is too big, but this reason makes no sense to me in this case.
Thank you for your help!

cPanel Manage2 for WHMCS 1.4.0 module with new pricing model support! | NewProxyLists

1. cPanel Manage2 for WHMCS v1.4.0

To make cPanel Manage2 For WHMCS even more attractive to the public and fully aware of the latest cPanel pricing changes, we've added a few upgrades to our module. Let's take a look at version 1.4.0.

From now on, you will be offered the choice of two additional billing types, both are based on the current number of accounts assigned to the client's cPanel license.

  • Option "flexible" – charge customers the exact number of accounts assigned to a single license up to the specified synchronization date
  • "Multilevel" option – Define account number levels and charge customers based on the nearest available level

What's more, we have completed all the necessary test steps to confirm that the module can now be safely installed in the system. WHMCS 7.8 environment! What is the point of waiting then?

Learn more about cPanel Manage2 For WHMCS 1.4.0!

2 Custom Report for WHMCS – Promotion

Tracking a series of specific metrics to make the right decisions is the foundation for the steady growth of your business. And here is where our Report Generator for WHMCS module intervenes!

Do a search in the ever growing selection of ready-made reports, generate your own or better yet … let us build a tailor-made report exclusively for you, without additional payment!

Simply enter the module on our website and contact our team so that we can reflect on your needs in detail.

Jump on the opportunity to run your business like a pro!

3 the WHMCS 7.8 Support List is expanding day by day! Check if your favorite modules have already adopted full compatibility:

Look for more modules already integrated!

Do you need a bespoke software for your business?

We will specially tailor for you an application and its design to your own needs, create a new module or even an entirely new system built from scratch!

android – Is it possible to create an application in this model?

question

Good night person!

I would very much like to receive a response from you in which I create an application on the mobile that contains its information such as: messages that were sent (what is, face, etc.), outgoing calls, a keylogger, and others. I know that there are authorization codes and many of others are:

The question I was trying to find out is: how can I get these permissions created in the app to receive phone messages, among others, and when I install the application? on the phone, send the information to a site containing a panel (I took an impression of the panel), to perform their viewing?

Image where I take an example of the Spyzie website

I want to create an app so that parents can control their kids, but I wanted to know first if you have the opportunity, research, research, and conclusions, but I wanted to confirm here.

Where can I start?

What should I study specifically to create both?

As far as I know, is it a web service that creates an API between Android and Page? HELP PLS !!!

c # – The layer of domain model entity depends on the persistence layer here?

I'm trying to apply domain-driven design here in this bank simulation application.

I have 3 layers at the moment:

  • Domain Model Entity Layer (Pure POCO Classes)
  • Persistence layer (Entity Framework)
  • Layer of the console user interface

In the persistence layer, I have the RepositoryTransaction class that performs the CRUD operation.

namespace ATM.Persistance.Repository
{
public class RepositoryTransaction
{
    private readonly AppDbContext db;

    public RepositoryTransaction()
    {
        db = new AppDbContext();
    }

    public int AddTransaction(Transaction transaction)
    {
        db.Transactions.Add(transaction);
        return db.SaveChanges();
    }
}
}

In my domain model entity layer, I have the BankAccount class.

public class BankAccount
{
    public int Id { get; set; }
    public string AccountName { get; set; }
    public decimal Balance { get; set; }

    // To create RepositoryTransaction to call AddTransaction method.
    // But according to Domain-Driven Design, domain model layer should not depend on
    // any layer, right? But here, it depends on Persistance layer.
    // If it doesn't depend on Persistance layer, then where do I do so? In Console UI Core?
    // private readonly RepositoryTransaction repoTrans = new RepositoryTransaction();

    public decimal CheckBalance()
    {
        return Balance;
    }

    public void Deposit(int amount)
    {
        // Domain logic
        Balance += amount;

        // Add transaction
        var transaction = new Transaction()
        {
            Id = 1,
            TransactionDateTime = DateTime.Now,
            Amount = amount,
            TransactionType = TransactionType.Deposit
        };

        // repoTrans.AddTransaction(transaction);
    }

    public void Withdraw(int amount)
    {
        // Domain logic
        Balance -= amount;

        var transaction = new Transaction()
        {
            Id = 2,
            TransactionDateTime = DateTime.Now,
            Amount = amount,
            TransactionType = TransactionType.Withdraw
        };

        // repoTrans.AddTransaction(transaction);
    }
}

and in the console UI, I have the Program class and the Main method:

namespace ATM.ConsoleUICore
{
class Program
{
    static void Main()
    {
        var bankAccount = new BankAccount() { Id = 1, AccountName = "John", Balance = 250M };

        Console.WriteLine("1. Check balance");
        Console.WriteLine("2. Deposit");
        Console.WriteLine("3. Withdraw");
        Console.WriteLine("Enter option: ");
        string opt = Console.ReadLine();
        switch (opt)
        {
            case "1":
                Console.WriteLine($"Your balance is ${bankAccount.CheckBalance()}");
                break;
            case "2":
                // User to input amount.
                // Data validation to make sure amount is greater than zero.

                bankAccount.Deposit(50);
                Console.WriteLine("Deposit successfully");
                break;
            case "3":
                // User to input amount.
                // Data validation to make sure amount is greater than zero.

                bankAccount.Withdraw(20);
                Console.WriteLine("Withdraw successfully");
                break;
            default:
                break;
        }

    }
}
}

My question is written in the BankAccount class. According to domain design, domain model layer should not depend on any layer, right? But here, that depends on the persistence layer. If it does not depend on the persistence layer, then where should I do it? In the console UI layer?

8 – How to discover the currently active twig model

I need to find the Twig model currently active in the module pretreat feature.

function mymodule_preprocess_field(&$variables, $hook) {
    // How do i retrieve the currently active Twig template?
}

I need to know if this is field.html.twig, field--field-example.html.twig or another model suggestion.

Is it possible?

coupon – Magento which model is correct to get the quote in the cart?

I have tried all model models that return a quote in order to try to find the one containing the quote for the current customer's cart.

Until now, none of them works, and I can not understand why this could be.

Essentially, I run an external script in the misc directory that defines a coupon code generated on the current cart, but none of the following correctly defines the code and I must redirect the redirection to / checkout / cart / coupon / post or whatever the correct URL is for that.

Here are the different models that I tried to get the session:

$session = Mage::getSingleton("customer/session");
$session = Mage::getSingleton('checkout/session');
$session = Mage::getSingleton('core/session');
$session = Mage::getSingleton("core/session",  array("name"=>"frontend"));

And these are the different methods that I have tried to use on the quote:

$quote->getShippingAddress()->setCollectShippingRates(true);
$quote->setCartCouponCode($coupon);
$quote->setCouponCode($coupon);
$quote->collectTotals();
$quote->save();

They do not fail but they do not define the code correctly either.

mysql – How to model a type of entity that can have different sets of attributes?

According to your description of the business environment considered, there is a supertype subtype structure that encompasses article -The supertype- and each of its Categories, that is to say., Car, Boat and Plane (as well as two other unknowns) – the subtypes -.

I will detail below the method I would follow to manage such a scenario.

In order to start delineating the relevant areas conceptual schema, some of the most important trade rules determined so far (by limiting the analysis to the three Categories only, so that things are as brief as possible) can be formulated as follows:

  • A User has zero-one-or-more goods
  • A article belongs to exactly one User at a specific moment
  • A article can belong to one or more users at different times
  • A article is ranked by exactly one Category
  • A article is, at any time,
    • be a Car
    • or one Boat
    • or one Plane

Figure 1 shows an IDEF1X1 diagram that I have created to group previous formulations with other management rules that seem relevant:

Figure 1 - Type and subtype structure of element and category supertype

supertype

From one side, article, the supertype, presents the properties or attributes that are common to all Categories, that is to say.,

  • CatégorieCode – specified as a foreign key (FK) which reference Catégorie.CatégorieCode and works as a subtype discriminatorthat is to say that it indicates the exact Category subtype with which a given article must be connected-,
  • ownerid "Distinguished as an FK pointing to User.UserIdbut I assigned him a role name2 to more accurately reflect its particular implications,
  • foo,
  • Bar,
  • Baz and
  • CreatedDateTime.

Subtypes

On the other hand, the properties that relate to each particular Category, that is to say.,

  • qux and Corge;
  • Grault, Garply and Pugh;
  • xyzzy, Thud, Nibble and Flob;

are displayed in the corresponding subtype area.

Identifiers

Then Item.ItemId PRIMARY KEY (PK) migrated3 subtypes with different role names, that is,

  • carID,
  • BoatId and
  • PlaneId.

Mutually exclusive associations

As illustrated, there is an association or relationship of cardinality One by one (1: 1) between (a) each super-type occurrence and (b) its complementary subtype instance.

the exclusive subtype This symbol represents the fact that the subtypes are mutually exclusive, that is, one article This occurrence can only be completed by one subtype: one or the other. Car, or a Plane, or a Boat (never by two or more).

, I've used classic reservation settings names to assign rights to certain entity type properties, their actual names not being provided in the question.

Therefore, in order to discuss a logical repository design, I derive the following SQL-DDL statements based on the displayed IDEF1X diagram and described above:

-- You should determine which are the most fitting 
-- data types and sizes for all your table columns 
-- depending on your business context characteristics.

-- Also, you should make accurate tests to define the 
-- most convenient INDEX strategies based on the exact 
-- data manipulation tendencies of your business context.

-- As one would expect, you are free to utilize 
-- your preferred (or required) naming conventions. 

CREATE TABLE UserProfile (
    UserId          INT      NOT NULL,
    FirstName       CHAR(30) NOT NULL,
    LastName        CHAR(30) NOT NULL,
    BirthDate       DATE     NOT NULL,
    GenderCode      CHAR(3)  NOT NULL,
    Username        CHAR(20) NOT NULL,
    CreatedDateTime DATETIME NOT NULL,
    --
    CONSTRAINT UserProfile_PK  PRIMARY KEY (UserId),
    CONSTRAINT UserProfile_AK1 UNIQUE ( -- Composite ALTERNATE KEY.
        FirstName,
        LastName,
        GenderCode,
        BirthDate
    ),
    CONSTRAINT UserProfile_AK2 UNIQUE (Username) -- ALTERNATE KEY.
);

CREATE TABLE Category (
    CategoryCode     CHAR(1)  NOT NULL, -- Meant to contain meaningful, short and stable values, e.g.; 'C' for 'Car'; 'B' for 'Boat'; 'P' for 'Plane'.
    Name             CHAR(30) NOT NULL,
    --
    CONSTRAINT Category_PK PRIMARY KEY (CategoryCode),
    CONSTRAINT Category_AK UNIQUE      (Name) -- ALTERNATE KEY.
);

CREATE TABLE Item ( -- Stands for the supertype.
    ItemId           INT      NOT NULL,
    OwnerId          INT      NOT NULL,
    CategoryCode     CHAR(1)  NOT NULL, -- Denotes the subtype discriminator.
    Foo              CHAR(30) NOT NULL,
    Bar              CHAR(30) NOT NULL,
    Baz              CHAR(30) NOT NULL,  
    CreatedDateTime  DATETIME NOT NULL,
    --
    CONSTRAINT Item_PK             PRIMARY KEY (ItemId),
    CONSTRAINT Item_to_Category_FK FOREIGN KEY (CategoryCode)
        REFERENCES Category    (CategoryCode),
    CONSTRAINT Item_to_User_FK     FOREIGN KEY (OwnerId)
        REFERENCES UserProfile (UserId)  
);

CREATE TABLE Car ( -- Represents one of the subtypes.
    CarId INT      NOT NULL, -- Must be constrained as (a) the PRIMARY KEY and (b) a FOREIGN KEY.
    Qux   CHAR(30) NOT NULL,
    Corge CHAR(30) NOT NULL,   
    --
    CONSTRAINT Car_PK         PRIMARY KEY (CarId),
    CONSTRAINT Car_to_Item_FK FOREIGN KEY (CarId)
        REFERENCES Item (ItemId)  
);

CREATE TABLE Boat ( -- Stands for one of the subtypes.
    BoatId INT      NOT NULL, -- Must be constrained as (a) the PRIMARY KEY and (b) a FOREIGN KEY.
    Grault CHAR(30) NOT NULL,
    Garply CHAR(30) NOT NULL,   
    Plugh  CHAR(30) NOT NULL, 
    --
    CONSTRAINT Boat_PK         PRIMARY KEY (BoatId),
    CONSTRAINT Boat_to_Item_FK FOREIGN KEY (BoatId)
        REFERENCES Item (ItemId)  
);

CREATE TABLE Plane ( -- Denotes one of the subtypes.
    PlaneId INT      NOT NULL, -- Must be constrained as (a) the PRIMARY KEY and (b) a FOREIGN KEY.
    Xyzzy   CHAR(30) NOT NULL,
    Thud    CHAR(30) NOT NULL,  
    Wibble  CHAR(30) NOT NULL,
    Flob    CHAR(30) NOT NULL,  
    --
    CONSTRAINT Plane_PK         PRIMARY KEY (PlaneId),
    CONSTRAINT Plane_to_Item_PK FOREIGN KEY (PlaneId)
        REFERENCES Item (ItemId)  
);

As demonstrated, the type of superentity and each of the types of sub-entities are represented by the based table.

The columns CarId, BoatId and PlaneId, constrained as PK of the appropriate tables, help to represent the one-to-one conceptual level association by means of FK constraints§ this point to the ItemId column, which is constrained as PK of the Item table. This means that in a real "pair", the supertype and subtype lines are identified by the same PK value; it is therefore more than timely to mention that

  • (a) attach a additional column to hold the system-controlled substitution values to (b) the tables corresponding to the subtypes are (c) completely superfluous.

§ To avoid problems and errors concerning (especially the words FOREIGN) the KEY constraint definitions (the location you referred to in the comments), it is very important to take into account dependence on existence this happens between the different tables available, as shown in the statement order of the DDL structure tables of the exponent, which I have also provided in this SQL Fiddle.

For example, adding an additional column with the AUTO_INCREMENT property to a table of a database built on MySQL.

Integrity and consistency considerations

It is important to note that in your work environment, you must (1) ensure that each row of "supertype" is at any time completed by its corresponding "subtype" counterpart, and, in turn, (2) guarantee that the "subtype" line is compatible with the value contained in the "discriminator" column of the "supertype" line.

It would be very elegant to apply such circumstances in a declarative as far as I know, unfortunately, none of the big SQL platforms has provided the proper mechanisms to do this. Therefore, using the procedure code in ACID TRANSACTIONS is very convenient so that these conditions are always met in your database. Another option would be to use TRIGGERS, but they tend to make things messy, so to speak.

Having a logical design like the one explained above, it would be very convenient to create one or more views, ie. derivative tables that include columns belonging to two or more of the relevant elements. based the tables. In this way, you can, for example, select directly from these views without having to write all the JOINs each time you have to retrieve "combined" information.

Sample of data

In this regard, assume that the base tables are "populated" with the sample data presented below:

--

INSERT INTO UserProfile 
    (UserId, FirstName, LastName, BirthDate, GenderCode, Username, CreatedDateTime)
VALUES
    (1, 'Edgar', 'Codd', '1923-08-19', 'M', 'ted.codd', CURDATE()),
    (2, 'Michelangelo', 'Buonarroti', '1475-03-06', 'M', 'michelangelo', CURDATE()),
    (3, 'Diego', 'Velázquez', '1599-06-06', 'M', 'd.velazquez', CURDATE());

INSERT INTO Category 
    (CategoryCode, Name)
VALUES
    ('C', 'Car'), ('B', 'Boat'), ('P', 'Plane');

-- 1. ‘Full’ Car INSERTion

-- 1.1 
INSERT INTO Item
    (ItemId, OwnerId, CategoryCode, Foo, Bar, Baz, CreatedDateTime)
VALUES
    (1, 1, 'C', 'This datum', 'That datum', 'Other datum', CURDATE());

 -- 1.2
INSERT INTO Car
    (CarId, Qux, Corge)
VALUES
    (1, 'Fantastic Car', 'Powerful engine pre-update!');

-- 2. ‘Full’ Boat INSERTion

-- 2.1
INSERT INTO Item
  (ItemId, OwnerId, CategoryCode, Foo, Bar, Baz, CreatedDateTime)
VALUES
  (2, 2, 'B', 'This datum', 'That datum', 'Other datum', CURDATE());

-- 2.2
INSERT INTO Boat
    (BoatId, Grault, Garply, Plugh)
VALUES
    (2, 'Excellent boat', 'Use it to sail', 'Everyday!');

-- 3 ‘Full’ Plane INSERTion

-- 3.1
INSERT INTO Item
  (ItemId, OwnerId, CategoryCode, Foo, Bar, Baz, CreatedDateTime)
VALUES
  (3, 3, 'P', 'This datum', 'That datum', 'Other datum', CURDATE());

-- 3.2
INSERT INTO Plane
    (PlaneId, Xyzzy, Thud, Wibble, Flob)
VALUES
    (3, 'Extraordinary plane', 'Traverses the sky', 'Free', 'Like a bird!');

--

Then, an advantageous view is that which groups the columns of Item, Car and UserProfile:

--

CREATE VIEW CarAndOwner AS
    SELECT C.CarId,
           I.Foo,
           I.Bar,
           I.Baz,
           C.Qux,
           C.Corge,           
           U.FirstName AS OwnerFirstName,
           U.LastName  AS OwnerLastName
        FROM Item I
        JOIN Car C
          ON C.CarId = I.ItemId
        JOIN UserProfile U
          ON U.UserId = I.OwnerId;

--

Of course, a similar approach can be followed so that you can also SELECT the Boat and Plane information directly from one table (a derivative, in these cases).

After that – if the presence of NULL marks in the result sets does not bother you – with the following VIEW definition, you can, for example, "collect" columns from the tables. Item, Car, Boat, Plane and UserProfile:

--

CREATE VIEW FullItemAndOwner AS
    SELECT I.ItemId,
           I.Foo, -- Common to all Categories.
           I.Bar, -- Common to all Categories.
           I.Baz, -- Common to all Categories.
          IC.Name      AS Category,
           C.Qux,    -- Applies to Cars only.
           C.Corge,  -- Applies to Cars only.
           --
           B.Grault, -- Applies to Boats only.
           B.Garply, -- Applies to Boats only.
           B.Plugh,  -- Applies to Boats only.
           --
           P.Xyzzy,  -- Applies to Planes only.
           P.Thud,   -- Applies to Planes only.
           P.Wibble, -- Applies to Planes only.
           P.Flob,   -- Applies to Planes only.
           U.FirstName AS OwnerFirstName,
           U.LastName  AS OwnerLastName
        FROM Item I
        JOIN Category IC
          ON I.CategoryCode = IC.CategoryCode
   LEFT JOIN Car C
          ON C.CarId = I.ItemId
   LEFT JOIN Boat B
          ON B.BoatId = I.ItemId
   LEFT JOIN Plane P
          ON P.PlaneId = I.ItemId               
        JOIN UserProfile U
          ON U.UserId = I.OwnerId;

--

The code of views presented here is only illustrative. Of course, some test drills and modifications can help speed up the (physical) execution of queries. In addition, you may have to delete or add columns to these views based on the needs of the business.

The sample data and all view definitions are embedded in this SQL Fiddle so that they can be observed in action.

Manipulation of data: application program code and column alias

The use of application program code (if that is what you mean by "server-specific code") and column aliases are other important points that you have mentioned in the next comments:

  • I've managed to work around (a joint) problem with server-specific code, but I really do not want to do that-and-adding aliases to all columns could be "stressful" .

  • Very well explained, thank you very much. However, as I suspected, I will have to manipulate the result set by listing all the data because of the similarities with some columns because I do not want to use multiple aliases to keep the instruction cleaner.

It is appropriate to indicate that if the use of the application program code is a very useful resource to manage presentation features (or graphics) sets of results, it is essential to avoid data recovery line by line to avoid speed problems. The goal should be to "recover" the relevant datasets in their entirety using the robust data manipulation tools provided by the (precisely) SQL platform engine to optimize the behavior of your system.

In addition, using aliases to rename one or more columns to a certain extent may seem stressful, but I personally consider this resource a very powerful tool that allows (i) contextualizing and (ii) disambiguating the meaning and intention assigned to the columns concerned; therefore, this is an aspect that needs to be carefully considered in the handling of data of interest.

You might as well find help for this series of publications and this group of publications which contains my opinion on two other cases that include supertype associations with mutually exclusive subtypes.

I've also proposed a solution for a professional environment involving a supertype type cluster where the subtypes are do not mutually exclusive in this (more recent) answer.


1Definition of integration for information modeling (IDEF1X) is a highly recommended data modeling technique, established as a Standard in December 1993 by the United States National Institute of Standards and Technology (NIST). It is firmly based on (a) some of the theoretical work written by the single origin the relational model, namely Dr. E. F. Codd; on (b) the entity-relationship vision, developed by Dr. P. P. Chen; and also on (c) the logical database design technique, created by Robert G. Brown.

2 In IDEF1X, a role name is a distinctive label assigned to an FK property (or attribute) to express its meaning in the field of its respective entity type.

3 The IDEF1X standard defines key migration as "The modeling process of placing the primary key of a parent or generic entity in its child entity or category as a foreign key".

types of inductive data – Rooster Model (pCuIC) in heights?

Can Cock Type Theory (pCuIC) be modeled in all higher Grothendieck topos?
First, even the overall theoretical model is not complete (eg, inductive types in Prop). Although it should work.
Shulman has shown that the theory of types with W types can be interpreted in higher Grothendieck topos. Inductive families can be reduced to W-types. These would be similar to the inductive families of Coq. However, I am not sure I have ever seen a specific result in that sense.
Voevodsky has made a similar reduction for the inductive types of Rooster, but I am not sure whether it is entirely up to date or complete. The note has never been published. In addition, it was written before the release of pCuIC.
Finally, Coq also has co-inductive types. Again, the M types can be interpreted in HoTT, but I am not aware of a reduction in co-inductive types of Rooster in M ​​types.