Learn SQL
using MySQL

Prateek Narang
Let's Learn
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Programming Languages
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C++ History
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C++ Advantages & Applications


SELECT – the columns in the result set
FROM – names the base table(s) from which results will be retrieved
WHERE – specifies any conditions for the results set (filter)
ORDER BY – sets how the result set will be ordered
LIMIT – sets the number of rows to be returned

SELECT Statement
Variable name: A label for a memory location
Value: The something that would be stored in a variable
Storage: A place where data can be stored
Declaration: Announcing a variable (usually) at the beginning of a program
Naming convention: A set of rules about the names of variables
Assignment: Giving (setting) a variable a value

Variables



// Valid names
int topics = 3
int marks = 20
int student_1 = 5
// Invalid Names
1_student = 8;
Naming Convention
- For variable name we can use uppercase and lowercase letters, digits from 1 to 9 and underscore(_).
- First character must be underscore or letter.
- C++ is strongly typed language. So every variable needs to be declare before using it

Variable Initialisation
Variables when just declared have garbage value until they are assigned a value for the first time.
We can assign a specific value from the moment variable is declared, called as initialisation of variable.
// Declare
int marks;
// Declare + Assign (Init)
int x = 10;

CODE DEMO

Topics Template
By Prateek Narang
Topics Template
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