Web hosting plans

In this blog post I am going to walk through the web hosting plans I have personally used, their pros and cons and also compare different hosting options that are available in the market.

Welcome back to my another blog post. Today I am going to share my experience hosting my websites. We will explore different options available in the market, their pros and cons and which option to pick and at what stage. I will also talk about my mistakes and lessons learned over the years. I hope this will act as a reference for someone out there thinking of hosting their first website. So, let's get started.

The beginning

I started making websites back in 2012, when I was a college student. Since 2014, I have been hosting my websites. Earlier I used to make static websites using just HTML, CSS and JavaScript along with jQuery.

By 2013, I was making dynamic websites using PHP and MySQL database and in 2014 I created my first website dyclassroom.com, an educational website. Over the years, I have deployed simple static websites, custom dynamic websites, websites using CodeIgniter framework, WordPress websites and blogs, websites built using React, Next.js, monoliths and microservices etc.

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PostgreSQL - Data Types

In this tutorial we will learn about of the commonly used data types in PostgreSQL.

About Data Types

Data types tells us about the type of data that is stored in a column.

Following are some of the commonly used data types in PostgreSQL.

• Numeric Type
• Boolean Type
• UUID Type
• XML Type
• JSON Type
• Monetary Type
• Character Type
• Binary Type
• Date/Time Type

Numeric Type

Numeric types helps us to store numbers. The following table lists the different numeric types.

• Integer
• Numeric and Decimal
• Floating point
• Serial

Integer

These data types are used to store integer values like -2, 0, 10 etc.

Data Type	Size (byte)	Min value	Max value
smallint	2	-32768	+32767
integer	4	-2147483648	+2147483647
bigint	8	-9223372036854775808	+9223372036854775807

Numeric and Decimal

Numeric and Decimal are of variable size as the precision is user specified.

Data Type	Size (byte)	Range
numeric	variable	up to 131072 digits before the decimal point; up to 16383 digits after the decimal point
decimal	variable	up to 131072 digits before the decimal point; up to 16383 digits after the decimal point

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PostgreSQL - Getting Started

This is an introduction to PostgreSQL database.

What is PostgreSQL?

PostgreSQL is a RDBMS or Relational Database Management System. It is one of the popular and most advanced open source relational database and was developed at Berkeley Computer Science Department (University of California).

Versions of PostgreSQL

PostgreSQL can be installed on Windows, Mac and Linux personal computers and can also be installed on servers like Google Cloud, AWS (Amazon Web Services) etc.

Connecting to the database using psql

After installing the PostgreSQL database on your computer you can connect to it using psql command from your terminal.

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How to install Postgres.app to use PostgreSQL database on Mac

In this tutorial we will learn to install Postgres.app to use PostgreSQL database on Mac.

What is Postgres.app?

Postgres.app is a full-featured PostgreSQL installation packaged as a standard Mac app. -- https://postgresapp.com

Download

Visit postgresapp.com and download the software on your Mac.

Run the installer and move the Postgres.app into the Applications directory.

Default settings

Postgres.app will install on your Mac with the following default settings.

Host	localhost
Port	5432
User	your system user name
Database	same as user
Password	none
Connection URL	postgresql://localhost

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ES6 - Template Literals (Template strings)

Watch the video tutorial: ES6 Template Literals (Template strings) #02

In this ES6 JavaScript tutorial we will learn about Template Literals (Template strings).

What are Template Literals?

Template literals are string literals that allows us to embed expressions, multi-line strings and string interpolation.

Template literals are enclosed using backtick ` ` instead of single quotes and double quotes.

Let's print the string Hello World using single and double quotes.

console.log('Hello World');
console.log("Hello World");

Now, let's print the same string using template literal.

console.log(`Hello World`);

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ES6 - var let const

Check out the tutorial video: ES6 var let const #01

In this ES6 JavaScript tutorial we will learn to create variables using var, let and const.

The var keyword

Alright, let's begin by creating a variable using the var keyword.

Let's say we want to create a variable x and assign it a value 10. So, we will write the following line.

var x = 10;

Now, if we want to print the value of x we can console log it by writing the following line.

var x = 10;
console.log(x);

And we get the output 10.

Few important points we must note while using the var keyword to declare variables.

We can redefine the same variable x again and we will not get any error.

So, we can write something like the following.

var x = 10;
console.log(x); // 10
var x = 20;
console.log(x); // 20

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How to install PostgreSQL on Mac using Homebrew

Click the link: "How to install PostgreSQL on Mac using Homebrew"

In this tutorial we will learn to install PostgreSQL database on Mac using Homebrew.

Prerequisite

It is assumed that you have Homebrew installed on your Mac.

If you don't have Homebrew installed on your Mac then open Terminal and run the following command.

$ /usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

Alright, time to install PostgreSQL on Mac.

Install PostgreSQL using Homebrew

In Terminal run the following command to install PostgreSQL on Mac using Homebrew.

$ brew install postgres

Start PostgreSQL

To start PostgreSQL run the following command in the Terminal.

$ brew services start postgres

Stop PostgreSQL

To stop PostgreSQL run the following command in the Terminal.

$ brew services stop postgres

Restart PostgreSQL

To restart PostgreSQL run the following command in the Terminal.

$ brew services restart postgres

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How to change default shell to bash on macOS Catalina

Click the link: "How to change default shell to bash on macOS Catalina"

In this tutorial we will learn to change default shell to bash on macOS Catalina 10.15.

With the release of macOS Catalina 10.15 on 7th October 2019 Apple made zsh as the default shell. You can learn more about it here.

From Apple:

By default, your Mac uses either zsh or bash as the command-line interpreter for the login shell and interactive shell:

• zsh (Z shell) is the default shell for all newly created user accounts, starting with the macOS Catalina beta.
• bash is the default shell in macOS Mojave and earlier.

If you want to make bash as your default command-line interpreter then perform the following steps.

Close Terminal if it is open.

Step 1: Open System Preferences and select Users & Groups

Click on the System Preferences icon or hit Cmd + Spacebar to open Spotlight and type System Preferences and open it.

Now, select Users & Groups.

Step 2: Unlock

At the bottom left you will see the lock. Click it and enter your password to unlock it.

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How to install Apache, MySQL, PHP on macOS Catalina 10.15

Click the link: "How to install Apache, MySQL, PHP on macOS Catalina 10.15"

In this tutorial we will learn to install Apache, MySQL, PHP on macOS Catalina 10.15.

About macOS Catalina

Apple released macOS Catalina 10.15 on 7th October 2019 and it includes Apache and PHP. So, all we have to do is enable them. Then install MySQL and we are ready for development. So, lets get started.

Note! Support for 32 bit apps is removed in Catalina so, all your 32 bit applications will no longer work. Kindly upgrade your applications.

Apple has also made zsh as the default shell. You can learn more about it here.

To change the default shell check the tutorial How to change default shell to bash on macOS Catalina.

We will be using the pre-installed Apache and PHP and we will download and setup MySQL database.

If you are using macOS Mojave then check out this tutorial How to install Apache, MySQL, PHP on macOS Mojave 10.14

Let's go ahead and configure our LAMP stack development environment on macOS Catalina.

Apache

The new macOS Catalina comes with Apache pre-installed. All we have to do is switch it on.

Open Terminal using macOS Spotlight or go to /Applications/Utilities and open Terminal.

To check the version of Apache installed run the following command in the Terminal.

$ httpd -v

Server version: Apache/2.4.41 (Unix)
Server built:   Aug 29 2019 19:01:57

Note! macOS Catalina comes with Apache 2.4.41

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MongoDB - Delete Documents

Click the link: "MongoDB - Delete Documents"

In this MongoDB tutorial we will learn to delete documents.

Login to your MongoDB server and insert the following documents.

For this tutorial I will insert the documents in the subscription collection.

> db.subscription.insertMany([
  {
    "firstname": "John",
    "lastname": "Doe",
    "uid": 1,
    "accountstatus": "ACTIVE",
    "plan": "TRIAL15DAYS",
    "modifiedAt": null,
    "createdAt": new Date()
  },
  {
    "firstname": "Jane",
    "lastname": "Doe",
    "uid": 2,
    "accountstatus": "ACTIVE",
    "plan": "PLAN30DAYS",
    "modifiedAt": null,
    "createdAt": new Date()
  },
  {
    "firstname": "Jim",
    "lastname": "Doe",
    "uid": 3,
    "accountstatus": "SUSPENDED",
    "plan": "PLAN60DAYS",
    "modifiedAt": null,
    "createdAt": new Date()
  },
  {
    "firstname": "Alice",
    "lastname": "Doe",
    "uid": 4,
    "accountstatus": "ACTIVE",
    "plan": "PLAN1YEAR",
    "modifiedAt": null,
    "createdAt": new Date()
  }
])

Note! We are using new Date() to set the createdAt to current date time.

Delete one document

We use the deleteOne method to delete one document from a given collection.

In the following example we are deleting document having uid equal to 4.

> db.subscription.deleteOne({ "uid": 4 })

Read more...

MongoDB - Update Documents

Click the link: "MongoDB - Update Documents"

In this MongoDB tutorial we will learn to update documents.

Login to your MongoDB server and insert the following documents.

For this tutorial I will insert the documents in the subscription collection.

> db.subscription.insertMany([
  {
    "firstname": "John",
    "lastname": "Doe",
    "uid": 1,
    "accountstatus": "ACTIVE",
    "plan": "TRIAL15DAYS",
    "modifiedAt": null,
    "createdAt": new Date()
  },
  {
    "firstname": "Jane",
    "lastname": "Doe",
    "uid": 2,
    "accountstatus": "ACTIVE",
    "plan": "PLAN30DAYS",
    "modifiedAt": null,
    "createdAt": new Date()
  },
  {
    "firstname": "Jim",
    "lastname": "Doe",
    "uid": 3,
    "accountstatus": "SUSPENDED",
    "plan": "PLAN60DAYS",
    "modifiedAt": null,
    "createdAt": new Date()
  },
  {
    "firstname": "Alice",
    "lastname": "Doe",
    "uid": 4,
    "accountstatus": "ACTIVE",
    "plan": "PLAN1YEAR",
    "modifiedAt": null,
    "createdAt": new Date()
  }
])

Note! We are using new Date() to set the createdAt to current date time.

Update one document

To update a single document we use updateOne method.

Syntax

db.collectionName.updateOne(filter, update)

Where, filter is the condition to get the required document and update is the part of the document we want to update.

In the following example we are updating the account status of user having uid equal to 3 from SUSPENDED to ACTIVE.

> db.subscription.updateOne(
  { "uid": 3 },
  {
    $set: { "accountstatus": "ACTIVE" },
    $currentDate: { "modifiedAt": true }
  }
)

We use $set operator to update the value of accountstatus.

We use $currentDate operator to set the modifiedAt to current date.

If we now fetch the above document we will get the following.

> db.subscription.find({ "uid": 3 }).pretty()

{
  "_id" : ObjectId("5d7715d5b385796f53d4c8ff"),
  "firstname" : "Jim",
  "lastname" : "Doe",
  "uid" : 3,
  "accountstatus" : "ACTIVE",
  "plan" : "PLAN60DAYS",
  "modifiedAt" : ISODate("2019-09-10T03:18:42.406Z"),
  "createdAt" : ISODate("2019-09-10T03:17:41.130Z")
}

Read more...

MongoDB - Query for Null and Missing fields

Click the link: "MongoDB - Query for Null and Missing fields"

In this MongoDB tutorial we will learn to query for Null and missing fields.

Login to your MongoDB server and insert the following documents.

For this tutorial I will insert the documents in the deliveryAddress collection.

> db.deliveryAddress.insertMany([
  {
    "addressLine1": "House #1, 2nd Street, 1st Main Road",
    "addressLine2": "Opposite Bakery",
    "city": "Bangalore",
    "state": "KA",
    "country": "India",
    "pincode": "560001",
    "contactphone": "919800000000",
    "contactperson": "John Doe"
  },
  {
    "addressLine1": "House #20, 3rd Street, 5th Main Road",
    "addressLine2": null,
    "city": "Bangalore",
    "state": "KA",
    "country": "India",
    "pincode": "560001",
    "contactperson": "Jane Doe"
  },
  {
    "addressLine1": "House #20, 5th Street, 10th Main Road",
    "addressLine2": null,
    "city": "Bangalore",
    "state": "KA",
    "country": "India",
    "pincode": "560001",
    "contactphone": null,
    "contactperson": "Jim Doe"
  }
])

Select all documents having null field

In the following example we are fetching all the documents that have addressLine2 field set to null value.

> db.deliveryAddress.find({ "addressLine2": null }).pretty()


{
  "_id" : ObjectId("5d76170f89ccf6fae0c7974b"),
  "addressLine1" : "House #20, 3rd Street, 5th Main Road",
  "addressLine2" : null,
  "city" : "Bangalore",
  "state" : "KA",
  "country" : "India",
  "pincode" : "560001",
  "contactperson" : "Jane Doe"
}
{
  "_id" : ObjectId("5d76170f89ccf6fae0c7974c"),
  "addressLine1" : "House #20, 5th Street, 10th Main Road",
  "addressLine2" : null,
  "city" : "Bangalore",
  "state" : "KA",
  "country" : "India",
  "pincode" : "560001",
  "contactphone" : null,
  "contactperson" : "Jim Doe"
}

The $exists operator

To check if a document does or does not contains a given field we use the $exists operator.

Syntax

We use the following syntax to fetch all the documents of a given collection that does contains a given field.

db.collectionName.find({ field: { $exists: true } })

We use the following syntax to fetch all the documents of a given collection that does not contains a given field.

db.collectionName.find({ field: { $exists: false } })

Read more...

MongoDB - Query an Array of Embedded Documents

Click the link: "MongoDB - Query an Array of Embedded Documents"

In this MongoDB tutorial we will learn to query an array of embedded documents.

Login to your MongoDB server and insert the following documents.

For this tutorial I will insert the documents in the books collection.

> db.books.insertMany([
  {
    "title": "The C Programming Language",
    "author": ["Brian Kernighan", "Dennis Ritchie"],
    "inventory": [
      { "warehouse": "W1", "qty": 3000 },
      { "warehouse": "W2", "qty": 750 }
    ]
  },
  {
    "title": "MongoDB in Action",
    "author": ["Kyle Banker"],
    "inventory": [
      { "warehouse": "W2", "qty": 100 },
      { "warehouse": "W3", "qty": 1500 }
    ]
  },
  {
    "title": "Node.js in Action",
    "author": ["Marc Harter", "Nathan Rajlich", "T. J. Holowaychuk", "Mike Cantelon"],
    "inventory": [
      { "warehouse": "W1", "qty": 100 },
      { "warehouse": "W3", "qty": 250 }
    ]
  }

]);

Select based on exact match of embedded document in an array

In the following example we are fetching all the documents having the exact embedded document { "warehouse": "W1", "qty": 100 } in the inventory array.

Note! The field order is important i.e. the first field of the embedded document must be "warehouse" and must have value "W1" and the second field of the embedded document must be "qty" and must have value 100.

> db.books.find({ "inventory": { "warehouse": "W1", "qty": 100 } }).pretty();



{
  "_id" : ObjectId("5d2d9afd81a3cd0a9239c121"),
  "title" : "Node.js in Action",
  "author" : [
    "Marc Harter",
    "Nathan Rajlich",
    "T. J. Holowaychuk",
    "Mike Cantelon"
  ],
  "inventory" : [
    {
      "warehouse" : "W1",
      "qty" : 100
    },
    {
      "warehouse" : "W3",
      "qty" : 250
    }
  ]
}

If we change the field order of the embedded document in the query then we will not get the result.

In the following query we are changing the field order of the embedded document to { "qty": 100, "warehouse": "W1" } and it gives us no result.

> db.books.find({ "inventory": { "qty": 100, "warehouse": "W1" } }).pretty();

Read more...

MongoDB - Query an Array

Click the link: "MongoDB - Query an Array"

In this MongoDB tutorial we will learn to query arrays.

Login to your MongoDB server and insert the following documents.

For this tutorial I will insert the following documents in the posts collection.

> db.posts.insertMany([
  {
    "title": "This is my first post!",
    "tags": ["awesome", "post", "blog"]
  },
  {
    "title": "Dinner time :)",
    "tags": ["food", "dinner", "fun"]
  },
  {
    "title": "Birthday Treat",
    "tags": ["fun", "food", "birthday", "treat", "party"]
  }
]);

Match exact array

In the following example we are going to fetch documents having exactly 3 elements in the array and values are awesome, post and blog in that order.

> db.posts.find({
  "tags": ["awesome", "post", "blog"]
}).pretty();


{
  "_id" : ObjectId("5d1b43d9085e37060f4c36b5"),
  "title" : "This is my first post!",
  "tags" : [
    "awesome",
    "post",
    "blog"
  ]
}

Note! If we change the positions of the array elements in the above query then we will not get the same result.

Query an array for an element

In the following example we are going to fetch all the documents having an array field tags that contains food as one of the element in the array.

> db.posts.find({ "tags": "food" }).pretty();


{
  "_id" : ObjectId("5d1b43d9085e37060f4c36b6"),
  "title" : "Dinner time :)",
  "tags" : [
    "food",
    "dinner",
    "fun"
  ]
}
{
  "_id" : ObjectId("5d1b43d9085e37060f4c36b7"),
  "title" : "Birthday Treat",
  "tags" : [
    "fun",
    "food",
    "birthday",
    "treat",
    "party"
  ]
}

Read more...

MongoDB - Query Embedded Document

Click the link: "MongoDB - Query Embedded Document"

In this MongoDB tutorial we will learn to query embedded documents.

In the previous tutorial we learned about how to query documents and about logical operators and how to select specific fields. Feel free to check that out.

Embedded or Nested documents

For this tutorial lets go ahead and create some embedded documents. So, connect to your MongoDB server and run the following command to insert some documents in the shapes collection.

> db.shapes.insertMany([
  {
    "shape": "rectangle",
    "item": "Rect 1",
    "dim": {
      "length": 10,
      "breadth": 20,
      "uom": "cm"
    }
  },
  {
    "shape": "rectangle",
    "item": "Rect 2",
    "dim": {
      "length": 20,
      "breadth": 30,
      "uom": "cm"
    }
  },
  {
    "shape": "rectangle",
    "item": "Rect 3",
    "dim": {
      "length": 5,
      "breadth": 10,
      "uom": "cm"
    }
  },
  {
    "shape": "square",
    "item": "Sq 1",
    "dim": {
      "side": 10.5,
      "uom": "cm"
    }
  },
  {
    "shape": "square",
    "item": "Sq 2",
    "dim": {
      "side": 20,
      "uom": "cm"
    }
  },
  {
    "shape": "square",
    "item": "Sq 3",
    "dim": {
      "side": 15,
      "uom": "inch"
    }
  },
  {
    "shape": "square",
    "item": "Sq 4",
    "dim": {
      "side": 25.5,
      "uom": "inch"
    }
  }
]);

We learned how to create embedded documents in the Insert Document tutorial. Feel free to check that out.

Alright, let's start simple then progress to advance problems.

Find all rectangles

To find all the documents in the shapes collection that represents a rectangle we have to run the following command.

> db.shapes.find({ "shape": "rectangle" }).pretty();


{
  "_id" : ObjectId("5d175dffba3250e57f98faca"),
  "shape" : "rectangle",
  "item" : "Rect 1",
  "dim" : {
    "length" : 10,
    "breadth" : 20,
    "uom" : "cm"
  }
}
{
  "_id" : ObjectId("5d175dffba3250e57f98facb"),
  "shape" : "rectangle",
  "item" : "Rect 2",
  "dim" : {
    "length" : 20,
    "breadth" : 30,
    "uom" : "cm"
  }
}
{
  "_id" : ObjectId("5d175dffba3250e57f98facc"),
  "shape" : "rectangle",
  "item" : "Rect 3",
  "dim" : {
    "length" : 5,
    "breadth" : 10,
    "uom" : "cm"
  }
}

Read more...