Skip to main content

Posts

Showing posts from March, 2019

Docker Lifecycle And Useful Docker Commands

Maintaining a large software application is not that easy task since it may have lots of dependencies and OS related configurations. What if you can create an OS image which already contains required libraries and configurations that needs to run your application? Then that would be really easy for software deployer to deploy their application easily on a cloud without doing a tedious task of setting up an OS environment. One possible solution to overcome this problem is to use a Virtual Machine. You can install all libraries, setting up configurations and take an image. When you need to deploy the application, you can simply start the machine with that image. A VM provide complete low-level machine to run an Operating System. But it does not perform faster due to VM’s operational overhead. In this case Container technology comes to rescue. Containers vs VMs VM is nothing more than a computer that executes a program. VM is running on top of software which called Hypervisor.

Transparent Data Encryption for Databases

If you are creating a software application that needs to store and retrieve data, then most probably you have to use Databases. Unless it is not an in-memory database, Database store data on the disk as a file. Your application may be running on a remote server and database also reside on a remote server. Your application may collect sensitive data such as passwords, bank account data, and health data etc. Imagine a hacker somehow login into your database server and stolen your database file. Now, Unfortunately Hacker able access to all of your information by reading that file. So, How could you overcome this problem? Encryption comes to Rescue Encryption commonly used in day to day network communication to hide data from the third party. Encryption scrambles your data by a given key. Only the person who knows the right key can read the real message. Encryption could be either symmetric or asymmetric. In this case, we just need symmetric encryption since the user does not need t

SQLite Frontend Internal Architecture

In a computer program, the database is the heart of handling data. It provides an efficient way of storing and retrieving data fast. Learning Database internal architecture in code level is not that so easy since Database has complex architecture. Looking into a complex database is not that easy because of the complexity. But, SQLite is a nice little compact database that used in millions of devices and operating systems. Interesting fact about the SQLite database is that, code is highly readable. All most all of the codes are well commented and architecture is highly layered. This post is to look at the high-level architecture of the SQLite database. As I early mentioned, SQLite has a highly layered architecture and that can be separated into seven layers. We will go through each of the layers one by one. Tokenizer First Layer is called Tokenizer. Purpose of the tokenizer is to create tokens for a given SQL query. Tokenizer scans SQL query from left to right and generates

Database Internel Architecture: SQLite

Introduction A database is an essential part of building a software system which used to store and read data efficiently. Here, We are going to discuss some architectural details of database implementation by using an early version of SQLite. SQLite is a small database application which used in millions of software and devices. SQLite invented by D.Richard Hipp in August 2000. SQLite is a high performance, lightweight relational database. If you are willing to learn internal of a database in coding level, then SQLite is the best open source database available out there with highly readable source code with lots of documentation. Reading later versions of SQLite become a little harder since it contains lots of new features. In order to understand the basic implementation of database internals, You should have good knowledge about data structures, some knowledge about Theory of Computing and how an operating system works. Here we are looking into the SQLite 2.5.0 version. Here