Consider the following table : PRODUCT Table : PRODUCT | PID | PNAME | PRICE | QUANTITY | | --- | --- | --- | --- | | P1001 | Eraser | 10.50 | 5 | | P1002 | Ball Pen | 15.00 | 2 | | P1003 | Gel Pen | 25.10 | 3 | | P1004 | Ruler | 5.00 | 1 | Find the output of the following SQL queries : (i) SELECT 10+MOD(QUANTITY,3) FROM PRODUCT WHERE PNAME = “Eraser”; (ii) SELECT ROUND(PRICE,2)*QUANTITY FROM PRODUCT WHERE QUANTITY > 2; (iii) SELECT UCASE(RIGHT(PNAME,2)) FROM PRODUCT;

Consider the following table : PRODUCT Table : PRODUCT — CBSE Class 12 Informatics Practices 2022 PYQ

Question

Consider the following table : PRODUCT

Table : PRODUCT

PID	PNAME	PRICE	QUANTITY
P1001	Eraser	10.50	5
P1002	Ball Pen	15.00	2
P1003	Gel Pen	25.10	3
P1004	Ruler	5.00	1

Find the output of the following SQL queries :

SELECT 10+MOD(QUANTITY,3) FROM PRODUCT WHERE PNAME = “Eraser”;
SELECT ROUND(PRICE,2)*QUANTITY FROM PRODUCT WHERE QUANTITY > 2;
SELECT UCASE(RIGHT(PNAME,2)) FROM PRODUCT;

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Concept understanding — Rounding And Arithmetic

Rounding and Arithmetic: A Concept-First Guide

Think about the last time you told someone your age. You probably said "twenty-two" or "thirty-five" — not "twenty-two years, four months, eleven days, and about six hours." That instinct to give a clean, sensible number instead of a painfully precise one is the entire spirit of rounding.

We round because life rarely needs the full, messy truth that numbers can carry. When you read that a company's revenue was "₹50 crore," it almost certainly wasn't exactly ₹50,00,00,000.00 — it was rounded to a meaningful figure. The same happens when you split a dinner bill, estimate travel time, or read a news headline about a budget deficit. Rounding is not about being sloppy; it is about being useful.

The Precise Meaning

Rounding is the process of replacing a number with a nearby number that is shorter, simpler, or easier to work with, while keeping it as close as possible to the original value. The key word is nearby — we do not invent a new number; we choose the nearest sensible one.

The "sensible" part depends on context. You might round to the nearest ten, the nearest hundred, the nearest thousand, or even the nearest lakh or crore. The choice is dictated by what level of detail matters for the purpose at hand.

Note

Rounding is not the same as approximation. Approximation is a broader idea — it includes rounding but also includes estimation, guessing, and using rough figures. Rounding is a specific, rule-governed way of cleaning up a number.

Why It Matters in Commerce and Humanities

In commerce, you deal with large figures — revenues, expenses, taxes, population counts, GDP. Carrying every digit to its decimal place is not only impractical; it can be misleading. A balance sheet that says ₹1,23,45,678.91 looks precise, but that precision is often false — the underlying data might itself be estimated. Rounding to ₹1.23 crore communicates the same information far more clearly.

In humanities — history, economics, political science — you encounter statistics constantly. A historian writing about the population of Delhi in 1901 does not need the exact census number to the last person. A rounded figure like "4 lakh" conveys the scale honestly, without pretending to a precision that the source material cannot support.

Important

The single most important rule of rounding is this: round only at the end of your work, never in the middle. If you are adding, subtracting, or comparing numbers, keep the full figures until you have your final result. Rounding too early introduces errors that compound — a mistake that can turn a small inaccuracy into a large one.

The Core Principle: What Gets Preserved

When you round, you are making a deliberate choice about what information to keep and what to discard. The rounded number should still be representative of the original. If you round 7,49,999 to the nearest lakh, you get 7 lakh — not 8 lakh — because 7,49,999 is closer to 7,00,000 than to 8,00,000. That is the logic: pick the nearest neighbour.

But there is a special case. What about 7,50,000? It sits exactly halfway between 7 lakh and 8 lakh. Here, convention steps in: we round up. This is not a mathematical necessity — it is an agreed-upon rule so that everyone gets the same answer. Without it, half-way numbers would be ambiguous.

Rounding preserves the order of magnitude — the scale of the number. …

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Let’s go through each query one by one, exactly as the SQL engine would execute it.

(i) SELECT 10+MOD(QUANTITY,3) FROM PRODUCT WHERE PNAME = "Eraser";

For the Eraser row, QUANTITY is 5.

MOD(5, 3) gives the remainder when 5 is divided by 3 — that is 2.

Then 10 + 2 = 12.

So the output is a single value: 12.

(ii) SELECT ROUND(PRICE,2)*QUANTITY FROM PRODUCT WHERE QUANTITY > 2;

This picks rows where QUANTITY is greater than 2. That means:

P1001 (Eraser): PRICE = 10.50, QUANTITY = 5 → ROUND(10.50, 2) = 10.50 → 10.50 * 5 = 52.50
P1003 (Gel Pen): PRICE = 25.10, QUANTITY = 3 → ROUND(25.10, 2) = 25.10 → 25.10 * 3 = 75.30

Output is two rows: 52.50 and 75.30.

(iii) SELECT UCASE(RIGHT(PNAME,2)) FROM PRODUCT; …

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This question tests your understanding of SQL functions — MOD, ROUND, UCASE, and RIGHT — by asking you to compute specific outputs from a given PRODUCT table.

Let’s look at the table first. It has four columns: PID (product ID), PNAME (product name), PRICE (in rupees, with two decimal places), and QUANTITY (number of units in stock). The data is straightforward — four products with their respective values.

Now, each query applies a different combination of SQL functions to extract or compute something. We’ll take them one by one.

(i) SELECT 10+MOD(QUANTITY,3) FROM PRODUCT WHERE PNAME = “Eraser”;

This query first filters the table to only the row where PNAME is “Eraser”. From that row, it takes the QUANTITY value — which is 5. The MOD function returns the remainder when QUANTITY is divided by 3. So MOD(5,3) gives 2 (since 5 ÷ 3 = 1 remainder 2). Then 10 is added to that result: 10 + 2 = 12.

Note

MOD is short for “modulo” — it’s the remainder after division. In NCERT textbooks, this function is used exactly as shown: MOD(a,b) returns the remainder when a is divided by b.

The output is a single number: 12.

(ii) SELECT ROUND(PRICE,2)*QUANTITY FROM PRODUCT WHERE QUANTITY > 2;

This query first selects rows where QUANTITY is greater than 2. Looking at the table, that means:

P1001 (Eraser) — QUANTITY 5
P1003 (Gel Pen) — QUANTITY 3

For each of these rows, the query does two things: it rounds the PRICE to 2 decimal places (which is already the case here — all prices have two decimals), then multiplies that rounded price by the QUANTITY.

For Eraser: ROUND(10.50,2) = 10.50, then 10.50 × 5 = 52.50

For Gel Pen: ROUND(25.10,2) = 25.10, then 25.10 × 3 = 75.30

Important

The ROUND function with a second argument of 2 simply ensures the price has exactly two decimal places. In this table, all prices already have two decimals, so ROUND doesn’t change the value — but it’s still applied as written. …

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Same / Similar Concept — real previous-year questions on the same or a closely similar concept, not this exact question.

CBSE 2025Set 90/1/11 mark
$Q. State whether the following statement is True or False: The MOD() function in SQL returns the quotient of division operation between two numbers.$
›Reveal solutionSolution
The MOD() function returns the remainder of a division, not the quotient. The statement is False.

The Concept: What MOD() Actually Does

The confusion comes from mixing up two different results of division. When you divide one number by another you get two things: a quotient (how many times the divisor fits into the dividend) and a remainder (what is left over). The MOD() function in SQL — short for "modulo" — always gives you the remainder.

Think about dividing 13 by 5. You can fit 2 fives into 13 (that is the quotient), but 3 is left over (that is the remainder). MOD(13, 5) gives you 3, not 2.

Step-by-Step Reasoning

1. Understand the operation. The modulo operation returns a - b × FLOOR(a / b) — the whole-number amount left over after dividing a by b.

2. Check what the statement claims. The statement says MOD() returns the quotient. The quotient of a divided by b is a / b (or its integer part). For example, the quotient of 13 ÷ 5 is 2.6 (or just 2 as an integer quotient) — a different value from the remainder.

3. Test with a concrete SQL example.

SELECT MOD(13, 5); -- returns 3 (the remainder) SELECT 13 / 5; -- returns 2.6 (the quotient, in most SQL dialects) ``` …
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CBSE 2025Set 90/1/11 markMCQ
$Q. Which SQL function calculates a^b? (A) MOD() (B) POWER() (C) RAISE() (D) ROUND()$
›Reveal solutionSolution

The SQL function that calculates a raised to the power b is POWER(), which takes two arguments — the base and the exponent — and returns the result.

In SQL, mathematical operations are handled by a set of built-in functions. When you need to raise one number to the power of another — say, 2 to the 3rd power to get 8 — you are performing an exponentiation. The function designed specifically for this is POWER().

POWER() takes two arguments: the base (the number you want to raise) and the exponent (the power to which you raise it). For example, POWER(2, 3) returns 8. This is the standard SQL function across most database systems, including MySQL, PostgreSQL, and Oracle.

Let's look at the other options to see why they are incorrect.

Note

MOD() returns the remainder of a division (e.g., MOD(10, 3) = 1). ROUND() rounds a number to a specified number of decimal places. Neither performs exponentiation. …

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CBSE 2024Set 90/1/11 markMCQ
$Q. What will be the output of the following query ? SELECT POWER(2,MOD(17,3)); (A) 8 (B) 1 (C) 0 (D) 4$
›Reveal solutionSolution
The query calculates 2 raised to the power of the remainder when 17 is divided by 3, giving 4. This is a common CBSE Class 12 Informatics Practices SQL math-function question.

In SQL, mathematical functions let you perform calculations directly inside a query. The query SELECT POWER(2,MOD(17,3)); nests two of them — MOD() and POWER() — so we evaluate it from the innermost function outward.

First the MOD() function:

MOD(dividend, divisor) returns the remainder when dividend is divided by divisor (the modulo operation).

Here the innermost call is MOD(17,3). Dividing 17 by 3 gives a quotient of 5 and a remainder of 2, because 17 = 3 × 5 + 2. So MOD(17,3) evaluates to 2.

Note

MOD() is handy for checking even or odd numbers (MOD(n, 2) = 0 means even), cyclic operations, and distributing items into groups.

Next, the result of MOD() (which is 2) becomes the second argument of POWER(), so the query effectively becomes SELECT POWER(2, 2);.

Now the POWER() function: …
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