SQL Mathematical Functions

Mathematical functions in SQL perform calculations on numeric values and return the result. These functions are commonly used while retrieving data from a database and help simplify complex calculations without modifying the stored data.

According to the CBSE Class 12 Informatics Practices syllabus, the following mathematical functions are included:

• POWER()
• ROUND()
• MOD()

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Why Use Mathematical Functions?

• Perform calculations directly in SQL queries.
• Reduce manual computation.
• Generate accurate reports.
• Improve query efficiency.
• Useful in business, banking, education, and analytics.

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1. POWER() Function

Syntax

POWER(number, exponent)

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Example 1

SELECT POWER(2,3);

Output

8

Because: 2 × 2 × 2 = 8

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Example 2

SELECT Name,
       POWER(Marks,2)
FROM Student;

Displays the square of the marks of each student.

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2. ROUND() Function

Syntax

ROUND(number, decimal_places)

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Example 1

SELECT ROUND(45.6789,2);

Output

45.68

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Example 2

SELECT ROUND(45.6789,0);

Output

46

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Example 3

SELECT Name,
       ROUND(Percentage,1)
FROM Student;

Displays the percentage rounded to one decimal place.

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3. MOD() Function

Syntax

MOD(dividend, divisor)

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Example 1

SELECT MOD(17,5);

Output

2

Because: 17 ÷ 5 = 3 remainder 2

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Example 2

SELECT MOD(24,6);

Output

0

The remainder is zero because 24 is completely divisible by 6.

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Using Mathematical Functions with a Table

Consider the following table:

RollNo	Name	Marks	Percentage
101	Amit	85	84.67
102	Neha	92	91.82
103	Rohan	78	77.45

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Example Queries

Square of Marks

SELECT Name,
       POWER(Marks,2)
FROM Student;

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Rounded Percentage

SELECT Name,
       ROUND(Percentage,1)
FROM Student;

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Find Odd or Even Roll Numbers

SELECT RollNo,
       MOD(RollNo,2)
FROM Student;

If the result is:

• 0 → Even Number
• 1 → Odd Number

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Comparison of Mathematical Functions

Function	Purpose	Example
POWER()	Raises a number to a power	POWER(2,3)
ROUND()	Rounds a number	ROUND(45.67,1)
MOD()	Returns remainder	MOD(17,5)

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Real-Life Applications

Function	Application
POWER()	Scientific calculations, compound interest
ROUND()	Salary, marks, GST calculations
MOD()	Checking odd/even numbers, cyclic operations

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Common Errors

Error	Reason
Syntax Error	Incorrect function syntax.
Unknown Column	Incorrect column name.
Incorrect Number of Arguments	Missing one or more function parameters.

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Quick Revision

Function	Purpose	Syntax
POWER()	Raise to a power	POWER(a,b)
ROUND()	Round a value	ROUND(a,n)
MOD()	Find remainder	MOD(a,b)

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CBSE Exam Tips

• Remember that POWER(number, exponent) calculates powers.
• Use ROUND(number, decimal_places) for rounding decimal values.
• MOD() is frequently used to check whether a number is odd or even.
• Practice writing SQL queries using these functions with table data.
• Understand the output of function-based SQL queries.

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Summary

SQL Mathematical Functions simplify numeric calculations while retrieving data from a database. The POWER() function raises a number to a given power, ROUND() rounds decimal values to the required precision, and MOD() returns the remainder after division. These functions are widely used in SQL queries for reporting, analysis, and real-world database applications.