Free SQL Courses

Data manipulation, sorting, and retrieval from relational databases are made easier with the use of SQL, a structured query language. Since the industrial world is entirely data-driven today, data is now the most significant key. Playing with data is necessary for more than just data analysts in the industrial world. Marketing, business, and many other fields depend on data management to sail smoothly. Learn this in-demand skill through Great Learning’s free SQL courses. 

SQL is rapidly used in data science and analytics. SQL allows users to retrieve data from the relational database and helps them to describe the structured data. It also allows users to create and manipulate the database and its tables. Using SQL, you can create a view, stored procedures, and functions in the relational database. Thus, it helps define the assembled data and modify them according to your relational database requirements. SQL also provides the users with the feature to set the permissions or constraints on the table columns, views, and stored procedures.

Coming to the syntax of the SQL:

• Keywords of SQL can be in both uppercase and lowercase, but in uppercase, the readability of the query is improved.
• SQL syntax is dependent on the text lines. Hence, you can place a single SQL statement on one or multiple text lines.
• Most of the actions can be performed by SQL queries in a database.
• SQL syntax relies on relational algebra and tuple relational calculus.

Some of the essential SQL commands include:

1.) CREATE DATABASE statement

It helps you to create the database.

Syntax: CREATE DATABASE database_name;

2.) SELECT statement

Reads the data in the database and presents it as the output to the user.

Syntax: 
SELECT column_name1,...,column_nameN
FROM table_name
WHERE condition;

3.) UPDATE statement

This statement is used to modify the stored data on the database.

Syntax: 

UPDATE table_name
SET column_name1 = new_value1,..., column_nameN = new_valueN
WHERE condition;

4.) INSERT INTO statement

It helps to insert data into the existing table of the database.

Syntax: 
INSERT INTO table_name
  (
    Column_name1, …, column_nameN
  )

  VALUES
  (
    value1,...,valueN
  );
 

COMMIT statement

It saves the changes permanently. It is usually done in transactions of the SQL database.

ROLLBACK statement

It helps to undo the transactions or operations that are not saved to the database.

When you execute any SQL command on any relational database management system, it automatically searches for the request to get processed in the best way. The SQL engine decides the interpretation of that command.

and. You can find four components in the SQL process: query dispatcher, optimization engines, classic query engine, and SQL query engine. Some of the SQL commands include CREATE, UPDATE, SELECT, DELETE, DROP, and INSERT. 

You can say RDBMS is the basis for SQL. RDBMS is a Relational Database Management System essential for many new database systems like Oracle, MS SQL Server, and more. Tables are used for storing and organizing the data in an RDBMS. The table consists of several smaller entities that define its purpose, known as fields. The table consists of rows(or records) and columns. There are many SQL constraints that the data columns of the table must follow.

Advantages of using SQL are: 

• Programming isn’t required
• Queries are processed at high speed, which supports portability 
• It is a standardized language
• It is an interactive language
• It supports more than one data view

Disadvantages include:

• Cost is high for the operation cost of a few SQL versions, 
• SQL interface is challenging to manage, makes the interface complex
• Business rules are hidden, which allows users to control the database partially and not full database access

Benefits of Learning SQL

SQL is a language used to interact with databases. It is the most widely used database language, and learning it can offer a range of benefits for professionals and organizations.

For Professionals

1. Increased knowledge and skills
One of the main advantages of learning SQL is that it increases data management knowledge and skills. SQL is a critical component of data analytics and data science, so a thorough understanding of it will make you a valuable employee and open up more job opportunities.

2. Understanding of how data works
By learning SQL, you can gain a much better understanding of how data works. With SQL, you can write queries to create, read, update, and delete data. This allows you to understand how data is stored and how it is used to answer questions.

3. Improved problem-solving abilities
SQL is an excellent tool for problem-solving. It can be used to solve complex problems related to databases, such as managing large amounts of data or providing insights from data. Learning SQL will help you develop better problem-solving skills.

For Organizations

1. Improved data management and analysis
SQL is used to manage and analyze data. By learning SQL, you can improve data management and analysis, which can significantly reduce costs and increase efficiency.

2. Enhanced security 
SQL can help prevent data breaches and enhance data security. It can also be used to identify and address any risks associated with data security.

3. Improved data accuracy and reliability
SQL can be used to ensure that data is accurate and reliable. With SQL, you can easily query data and find any issues in the data. This can help prevent mistakes and improve data accuracy and reliability.

All in all, learning SQL can offer a range of benefits for professionals and organizations. It can help increase knowledge and skills, improve problem-solving abilities, and enhance data security. Further, it can improve data management and analysis and ensure data accuracy and reliability. All these benefits make learning SQL a critical skill for anyone working in the field of data science or analytics.

In order thoroughly learn SQL, enroll in Great Learning’s free SQL courses that cover all the crucial concepts and earn free certificates of course completion. For advanced learning, look into Great Learning’s Best Software Development Courses, get hands-on experience in solving real-world problems, and earn a certificate of course completion that validates your skills.