NEB Class 12 • Computer Science • DBMS • Practice Set

Database Normalization Practice Set: NEB 12 Computer

Master Database Normalization through clear concepts, representations, a reliable answer method and exam-focused practice.

Student practising English listening with earbuds and study notes

Concepts · Worked reasoning · NEB practice

Quick answer: Normalization organizes relational tables to reduce update anomalies while preserving meaningful dependencies. First normal form uses atomic values, second removes partial dependency on a composite key, and third removes transitive dependency of non-key attributes.

Worked practice

Build the result from meaning, not memory

Normalization organizes relational tables to reduce update anomalies while preserving meaningful dependencies. First normal form uses atomic values, second removes partial dependency on a composite key, and third removes transitive dependency of non-key attributes.

Worked example

If Enrolment(student_id,course_id,student_name,course_title,grade) has key (student_id,course_id), move student_name and course_title to their entity tables while grade remains with enrolment.

The governing relationship is Find candidate keys and functional dependencies, then decompose stepwise while checking lossless join and dependency preservation rather than splitting tables mechanically. Check the convention, geometry or boundary condition before calculation.

Independent practice ladder

  1. Define the key physical quantities and give their SI units.
  2. Draw and label the relevant wave, ray, mode or energy diagram.
  3. Recalculate the worked example after changing one input by a factor of two.
  4. Explain the result without equations.
  5. Create a Nepal-relevant situation such as a classroom speaker, musical pipe, optical slit or thermal machine.
  6. Compare two cases and predict the larger output before calculating.
  7. Find and repair one deliberately wrong sign, node or unit.
  8. Write a three-mark answer and a five-mark answer.

Answer protocol: diagram → known data → principle → symbolic equation → SI substitution → result → physical check. Normalizing without identifying a key, confusing repeated rows with every form of redundancy, losing relationships during decomposition, or assuming more tables always mean better design.

NEB answer method

Model → evidence → equation → check

First identify the system and what the question asks. Label the diagram, apparatus or reaction with SI quantities, then state the principle before selecting an equation. Solve symbolically where possible and check units, limiting cases and chemical or physical meaning.

StageQuestionEvidence
ModelWhat is idealised?Assumption stated
RepresentationWhich diagram fits?Labels or balanced equation
CalculationWhich relation follows?Symbols then SI values
EvaluationDoes it make sense?Unit, sign and trend check

Make the idea concrete in Nepal

Connect the model to a school laboratory, household technology, health, environment, energy or local material. The example should clarify the science rather than merely mention a place. Compare a prediction with an observation and record uncertainty.

Review the NEB Class 12 Computer Science revision roadmap and the complete Computer Science guide. For online or physical tuition, call 9846662070.

Questions students ask about Database Normalization

What is the central idea of Database Normalization?

Normalization organizes relational tables to reduce update anomalies while preserving meaningful dependencies. First normal form uses atomic values, second removes partial dependency on a composite key, and third removes transitive dependency of non-key attributes.

Which equation should I remember?

Find candidate keys and functional dependencies, then decompose stepwise while checking lossless join and dependency preservation rather than splitting tables mechanically.

How should I begin a numerical?

Draw the situation, list known quantities in SI units, choose the governing relation symbolically, substitute once and finish with a unit and reasonableness check.

What is a common exam mistake?

Normalizing without identifying a key, confusing repeated rows with every form of redundancy, losing relationships during decomposition, or assuming more tables always mean better design.

How can I practise this topic?

Alternate one concept explanation, one diagram and two numericals. Revisit errors after a day instead of only rereading the solution.

Where can I get tuition support?

For online or physical KTM Tuition classes, call 9846662070. After Grade 12, the MKS Education panel below gives preparation and pre-counselling contacts.

Frequently asked questions

References and next steps

Scope checked against CDC Nepal; concept support from an institutional reference and OpenStax Science. Continue with the Database Normalization cluster.

NEB +2 tuition support

Ask about online or physical tuition

For focused Class 11 and Class 12 subject tuition, lesson clarification, worked-example practice and exam preparation, call 9846662070. Class mode, timetable, teacher availability and fees should be confirmed directly before enrolment.

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