Introduction to Database Systems
Database systems are used to store data. This data can be in numeric form, have some strings, data, time, pictures and huge or small files also.
Why we use Database?
In old days, the manual file system is used to store data and record transactions. When these files grow too huge, and we want to store books of accounts consisting of many registers. When searching some data from them is not an easy task, sometimes impossible and when we have to update something in it is also difficult.
Then with the evolution of computers, this manual system was converted to electronics file systems, but that took too much memory, with more loading time and difficult to maintain.
So the developers think of a system which should be secure, less time and effort consuming. As the solution database systems were introduced.
Databases take less space as we have to define the length of every variable and every attribute we store in it, so it takes care of every single bit. Databases use rows and columns, and it’s now too easy to search some data from the database and using some standard queries we quickly update and delete data from the database.
Advantages of Database:
We can also save passwords in the database in encrypted form to secure the data. The database has its security levels, so it’s not so easy to get in it without authentications. We can also save images in binary form to occupy less space.
As we say in databases we have rows and columns hierarchy, Columns define some particular attribute or entity and row represent the indexes or instance of these attributes.
As in above table we see there are three columns and every column is related to some characteristic of a person, like a person have ID. Name and city. So it will become the attributes of the person class and in database column of person table. Now if we have many persons, so we have to define one by one so for this we use rows. Every row contains one instance or object according to its attributes like in above example the ID attributes have two instances 1 and 2, which mean two persons have ID 1, and 2 and their names are Ali and Usman, and they live in City Taxila and Wah.
Now as we can see it’s a clear and well-managed way of storing data, and it’s easy for us to retrieve any data, update any data and insert or delete any data.
The most popular languages used to interact with database systems are SQL (standard query language), and now its refine and latest version same which is SQLi, which has both Object Oriented and Procedural implementation methods.
Popular Database Systems:
- The most popular and mostly used because of its simple interface and its easy to development in MS Access, which comes in MS (Micro soft) Office suite.
- The second most popular tool for the database is Oracle 10g, which was a product of Java.
- Another Microsoft database product is SQL Server Management Studio.
- The fourth most popular server used for database development is MyPHPAdmin with is a product of Bitnami.
Database has provided its user two types of jobs
- Database Developers
- Database Administrator
As there name database, the developer is the one who create a database and database administrator is the one who manage it.
In computer science field the use of the database is too much, everyone use database in his project as an essential part of the project here is a list of the project where the databases have some unique task i.e. to store data, in commonly used projects like.
- Room reservation systems
- Shopping mall software
- Inventory management systems
- Library management systems
- School management systems
- Social media applications, web apps.
Database supported languages:
Supporting languages mean by connecting with then you use database systems.
First of all the simpler one MS Access, it has all its working material, and you can easily create tables in its GUI mode generate queries of the tables and show records in its built-in forms.
MS Access and SQL can also be connected with JAVA (Java has its own database named as derby from apache also known as JavaDB) and C# to display the database data in some particular software systems created in these languages.
Oracle 10g and MS SQL server management studio both are enabled with JAVA and C# and VB.net also they have pre-defined syntax and libraries in these programming languages.