SQL: COUNT() Aggregate Function

The COUNT() function returns the number of rows in the specified table. There are two ways you can use COUNT(), which are the following:

1. COUNT(*) count all the rows in the table including
2. COUNT(column) return all the rows that contains value for the column, excluding the columns with null value

SELECT COUNT(*) AS NumberOfRows
FROM Customers

SQL: AVG() Aggregate Function

The AVG() function gets the average of a column, the following query gets the average of the UnitPrice column in the Northwind Products table.

SELECT AVG(UnitPrice) AS AveragePrice
FROM Products

Hour 14 ASP.NET Core: Seeding The NorwindCafe Database

In the previous blog we created the NorthwindCafe database with Entity Framework Core.  Now we are going to seed the database so that we can work with the data.

Here are the steps to seed the NorthwindCafe database:

1.  Create a file call DBInitializer in the NorthwindCafe.Web  "Models" folder, in the file type in the following code

using System.Linq;

namespace NorthwindCafe.Web.Models
{
    public class DbInitializer
    {
        public static void Initialize(NorthwindContext context)
        {
            context.Database.EnsureCreated();

            if(context.Categories.Any())
            {
                return;
            }

            var categories = new Category[]
            {
               new Category {Name = "Coffee", Description="Coffee", Products = new Product[] { new Product { Name = "Dark Roast", Description = "Dark Roast", Price = 2.0M } } },
               new Category {Name = "Tea", Description="Tea", Products = new Product[] { new Product { Name = "Chai", Description = "Chai", Price = 1.5M } } },
               new Category {Name = "Pastry", Description="Pastry", Products = new Product[] { new Product { Name = "Cupcake", Description = "Cupcake", Price = 1.25M } } },
               new Category {Name = "Food", Description = "Food", Products = new Product[] { new Product  { Name = "Hamburger", Description = "Hamburger", Price = 5.0M } } }
            };

            foreach (var c in categories)
            {
                context.Categories.Add(c);

            }

            context.SaveChanges();
        }
    }
}

Hour 13 ASP.NET Core : Add NorthwindContext To Startup Class And Create Database

In this post will are going to finally create the database that we have been preparing for in the last previous blog posts.  It's a two step process, first you have to add the NorthwindContext to the application in the Startup class, then you have to run the Entity Framework migration tool.

Here are the steps to create your NorthwindCafe database:

1.  Open the Startup.cs file, then type the following lines in the ConfigureServices method

 
            var connectionString = Configuration["Data:NorthwindContextConnection"];

            services.AddDbContext<NorthwindContext>(options => options.UseSqlServer(connectionString));

The line above gets the connection string from the appSettings.json file that we've created earlier. Then use the AddDbContext method in the services instance.  Dependency injection will take care of the plumbing for you.  Using lamba expression we tell the Entity Framework to use the Sql Sever provider for Entity Framework core.

Make sure you have the following namespaces in your Startup class

using NorthwindCafe.Web.Models;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.EntityFrameworkCore;

Hour 12 ASP.NET Core : Create The NothwindContext ( EntityFrameworkCore )

In our previous post we created the models for our Northwind Cafe application.  In this blog we will create the DbContext class which is the conduit between your entity classes and the database.  Think of it as a bridge that the database and the entity framework has to cross to get to each other.

Follow the steps below to create the NorthwindContext:

1. Create a class in Models folder call NorthwindContext

Hour 11 ASP.NET Core : Entity Framework Core Models For Northwind Cafe

In the previous post we added a configuration file call appSettings.json file to store our connection string to the database that we are going to create through Entity Framework.  Even though Microsoft provides us with the Northwind database, we don't really want to use it because it's outdated.  We are going to modernize the database by rebuilding it from scratch with the code first approach with Entity Framework Core.  If you look at the existing Northwind database you will see that there's a lot of redundant data and tables.  For example there are tables for Customers, Employees, Suppliers and Shippers.  Those are basically roles, and we will take care of those roles later on in the series using the Identity framework.  What we are going to do is start out simple with just the Products, Categories, Orders, OrderDetails table and add on to those tables as we progress in building the application.

CSS: text-transform

With text-transform you can transform your text into Autobots or Deceptacon? Not exactly, but what  you can do is transform your text to uppercase, lowercase, capitalize it. It's pretty self explanatory.

Here are the examples of a text-transform:

p.upper {text-transform:uppercase}
p.lower {text-transform:lowercase}
p.cap {text-transform: capitalize}

Here are the HTML markup:

            <p class="upper">uppercase me</p>
            <p class="lower">LOWERCASE ME</p>
            <p class="cap">captain america me</p>

Here is the output:

SQL: DATEPART Function

The DATEPART function extracts the date part of a date, for example using the 'yyyy' expression allows you to extract the year from a given date. The query below queries all the employees who were hired in the year 1994 in the Northwind Employees table.

SELECT FirstName + ' ' + LastName  AS Employee, HireDate
FROM Employees
WHERE DATEPART(yyyy,HireDate) = 1994

SQL: MAX() And MIN() Aggregate Functions

The MAX() function gets the highest value in the specified column, and the MIN() function gets the lowest value in the specified column

SELECT MAX(UnitPrice) AS HighestPrice, MIN(UnitPrice) AS LowestPrice
FROM Products

The query above gets the highest and lowest prices for the Products table in the Northwind database


 

CSS: Take Control Of Your Text Indentation With text-indent

Have you always wished to have more control with your text position, but feel like you limited with the text alignment of

Align Left text-align: left;







Here is the entire HTML markup:

<!DOCTYPE html>
<html>
    <head>
        <style>
            div { width: 800px}
            p.tdp {text-indent: -15%}
        </style>
    </head>
    <body>
        <div>
            <p class="tdp">Indent this text please Indent this text please Indent this text please Indent this text please</p>
            <p>This is just normal text This is just normal text This is just normal text This is just normal text This is just normal text</p>
        </div>
    </body>
</html>

CSS: The em Unit

There are often times when you see the measurement in CSS that looks something like this font-size: 2em; what does that actually mean? Well an em simply means its the multiplier of the font-size of the element. For instance 2em means that it will multiply the font-size of the element by 2x.

Let's say we have a div with a font-size of 15px, and there's a span tag with a font-size of 2em.  The span font-size of the span would be 30px, because the span is part of the div element.

Let's say have the following styles:

div {
  font-size: 15px;
}

span {
  font-size: 2em;
}

And with the following HTML markup:

<div>The font-size of the div element. <span>The span font-size</span>.</div>


The output is the following:









As you can see the span font-size is twice as big as the font-size of the div element.  Most people mistakenly think that em means the multiplier of the element size, but it is actually the size of the font of the element.

Here is the entire HTML markup:

<!DOCTYPE html>
<html>
    <head>
        <style>
            div {

                font-size: 15px;
            }

            span {
                font-size: 2em;
            }
        </style>
    </head>
    <body>
        <div>The font-size of the div element. <span>The span font-size</span>.</div>
    </body>
</html>

Digital Life: How To Tap Into The Apple Ecosystem Without An iPhone

I believe the last iPhone I owned was an iPhone 3?  I don't remember, but it was a while back.  It was actually a very good phone.  I love Apple products, but the price just seems to increase on each iterations and the features were less and less with each upgrades.  I found myself with a life or death situation.  Should I go to the dark side (Darth Vader breathing) an "Andriod Phone".  Oh my god, stop it I said to myself...lol  But at the time the Android phones were getting good.  So I decided to take the plunge and never looked back.

Anyways back to the present day, I have Apple envy because it has this great ecosystem, that I can't tapped into because I don't have an iPhone.  That is until I got the new iPad, which is the cheaper version of the iPad, but it's not really cheap at all it's the best iPad out there for the price.  I got it so that I can watch movies and read magazines while I was commuting.  What I found surprising was that once again I am tapped into the Apple ecosystem with my iPad.  I can sign up to all the new services that Apple is touting.  I am currently subscribed to News+ because I am a news junkie.  But if you think about it most of the new Apple services are ideal for consumption on a bigger screen.

Since I have unlimited plan on my Android phone, I used it as a hotspot for my iPad.  Put my iPad in a stylish mini bag, and I am good to go.  My iPad became a substitute for an iPhone, for less than 1K that's not bad. I know what you are thinking an Android phone and an iPad working together?  That's like the rebellion working with the empire.  But that's the closest thing to world piece right now and we should take it :)