SQL SELECT Command Basics

SELECT Command

The SELECT command is one of the most fundamental and frequently used commands in SQL.

It is used to retrieve data from a database table.

In simple terms, whenever you want to view or read data stored in a table, you use the SELECT command.

Important: The SELECT command does not modify the data. It only displays the requested information.

Understanding Database and Table

Before learning SELECT, it is important to understand two basic terms:

Think of a table as a spreadsheet:

Example: Students Table

id	name	marks
1	Rahul	85
2	Anjali	90

Why Use the SELECT Command?

The SELECT command is used to:

Syntax

SELECT column_name
FROM table_name;

Selecting All Columns from a Table

To retrieve all columns from a table, use the asterisk (*) symbol.

SELECT * FROM students;

Output

id	name	marks
1	Rahul	85
2	Anjali	90

The * symbol means all columns.

Selecting Specific Columns

To retrieve data from specific columns only, mention the column names separated by commas.

Example

SELECT name FROM students;

Output

name Rahul Anjali

name
Rahul
Anjali

Selecting Multiple Columns

SELECT name, marks FROM students;

Output


name marks
Rahul 85
Anjali 90

name	marks
Rahul	85
Anjali	90

Important Points to Remember

SQL keywords are typically written in uppercase (recommended practice)
Column and table names must match the database exactly
The SELECT command only retrieves data
Using SELECT * is convenient for learning but not recommended for large databases

Two Minute Drill