AccountsISC Class 12 · Database Management System

Database Management System: Concepts, Features and Business Applications, ISC Class 12

Updated 17 October 2026 · Draft, not yet fact-checked

A database is an organised collection of related data and a DBMS (Database Management System) is the software that creates, stores, updates and retrieves it. Its features include reduced duplication, data integrity, security, shared access and query facilities. In business, a DBMS design uses tables of records and fields linked by keys, with forms for entry, reports for output and indexes for fast search.

Understand DBMS: Concepts, Features, Types and Business Applications

Database and DBMS. A database is an organised collection of related data. A DBMS is the software, for example MySQL, Oracle, Microsoft Access or SQLite, that lets users define the structure of the data, enter and update it, and retrieve it. Updating and retrieving use basic SQL commands, covered on the next two topic pages.

Features of a DBMS. Controlled redundancy (less duplication), data integrity and accuracy, security through user rights, sharing among users, concurrent access, backup and recovery, and a query facility to ask questions of the data.

Types of DBMS (by the model used to organise data): hierarchical (tree of parent and child records); network (records linked in a web); relational (data in tables, linked by common fields; the commonest in business); object-oriented. A data model is a collection of conceptual tools for describing data, data relationships, data semantics and constraints.

Basic terms

Entity (a person, item or event about which data is stored) and its attributes (properties). In a table: table = entity set, field (column) = attribute, record (row) = one entity.
Primary key: a field (or fields) whose value uniquely identifies each record, such as InvNo; it cannot repeat or be empty.
Foreign key: a field in one table that holds the primary key of another table, creating a link.
Relationship: one-to-one, one-to-many (one customer has many invoices) or many-to-many.

Database design means describing the structure of the different parts of the database: the tables, their fields and data types, keys, and relationships. Good design stores each fact once and links tables by keys.

Forms, reports and indexing. A form is a screen for entering or viewing records one at a time. A report is a formatted output of selected data, such as a debtors list. An index is a lookup structure on a field that makes searching and sorting faster.

DBMS in business applications (syllabus examples)
1. Accounting information: tables for accounts, vouchers and transactions; reports give trial balance and ledgers.
2. Debtors and creditors: customer and supplier tables linked to invoice and receipt (or payment) tables; a report gives the balance of each party.
3. Bank reconciliation statement: tables of cash book entries and bank statement entries; entries that appear in only one table form the reconciling items.
4. Asset accounting: an asset table with cost, date, depreciation rate and accumulated depreciation; a report gives the book value.

A well-designed set of tables avoids the same customer name and address being typed on every invoice.

DBMS: Concepts, Features, Types and Business Applications: key facts

Table terms: Table = entity set
Field = column = attribute
Record = row = one entity; Relational model vocabulary.
Keys: Primary key: unique and not empty | Foreign key: primary key of another table; Foreign keys create relationships.
Debtor balance: Total invoices
less Total receipts
equals Balance due from the customer; A report over linked tables.
Bank reconciliation: Cash book balance
add or less items not in the cash book
equals Pass book balance; Items recorded in one record only.
Book value of an asset: Cost
less Accumulated depreciation
equals Book value; Asset accounting report.

How to answer DBMS: Concepts, Features, Types and Business Applications questions

For design questions, name tables, fields, keys and relationships; for report questions, say which tables are linked.

1List the entities (customer, invoice, receipt) and make a table for each.
2Choose a primary key for each table.
3Add foreign keys to link the tables; state the relationship type.
4Say what forms are needed for entry and what reports are needed for output.
5If numbers are given, compute the report from the linked tables.

DBMS: Concepts, Features, Types and Business Applications in real life

The idea, met in an everyday situation. Answer the question in your own words, then compare with the model answer. The one-line hook is what to remember.

Why store a customer once

Suppose a wholesaler has 3 customers and issues 40 invoices to each. In one design every invoice stores the customer's name and address. In another design the customer details sit in a Customer table and each invoice stores only the CustID.

One customer changes address. How many records must be updated in each design?

Try it first, then show the solutionSolution

First design: 40 invoices carry the address, so 40 updates.
Second design: the address sits once in the Customer table, so 1 update.

Answer: 40 updates against 1; the keyed design is quicker and cannot be left inconsistent.

Memory hook: Store a fact once; link it by key.

Tricks to remember DBMS: Concepts, Features, Types and Business Applications

Short memory aids. Say each one aloud once, then use it on a question the same day.

Field down, record across
Fields are columns; records are rows.
Use it when: Table terms.
P is for Proof of identity
The primary key proves which record this is; the foreign key points to another table's primary key.
Use it when: Keys.
F-R-I
Form in, Report out, Index to find.
Use it when: Three database objects.

DBMS: Concepts, Features, Types and Business Applications: solved examples

Ordered from board level to HOTS. Try each one before you open the solution.

Example 1: Naming the parts of a table · 1 mark · MCQBoard level

In a table of employees, the column "Salary" and one complete row of data are respectively called:
(a) record and field
(b) field and record
(c) key and index
(d) entity and relationship

Try it first, then show the solutionSolution

A column holds one attribute of every entity: a field.
A row holds all the data of one entity: a record.

Answer: (b) field and record

Example 2: Primary key and foreign key · 3 marks · Short answerBoard level

Distinguish between a primary key and a foreign key, with an example from a debtors database. (3 marks)

Try it first, then show the solutionSolution

A primary key uniquely identifies each record and cannot repeat or be empty: InvNo in the Invoice table.
A foreign key is a field that holds the primary key of another table to link the two: CustID in Invoice refers to CustID in Customer.
The primary key may appear once; the foreign key may repeat (one customer, many invoices).

Answer: Primary key: unique identifier of each record (InvNo). Foreign key: field referring to another table's primary key (CustID in Invoice).

Example 3: Debtors report from linked tables · 6 marks · Long answerHarder board level

A debtors database has Customer(CustID, Name, City), Invoice(InvNo, CustID, Amount) and Receipt(RcptNo, CustID, Amount). Data: customers C1 Asha Traders (Pune) and C2 Bilal Stores (Nagpur); invoices I1 C1 ₹15,000, I2 C1 ₹8,000, I3 C2 ₹12,000; receipts R1 C1 ₹10,000, R2 C2 ₹12,000. Name the keys and relationships, and prepare the debtors report showing the balance due from each customer and the total. (6 marks)

Try it first, then show the solutionSolution

Primary keys: CustID, InvNo, RcptNo. Foreign keys: CustID in Invoice and in Receipt. Relationships: one customer to many invoices; one customer to many receipts.
C1: invoices 15,000 + 8,000 = 23,000; receipts 10,000; balance 13,000.
C2: invoices 12,000; receipts 12,000; balance nil.
Total debtors = ₹13,000.

Answer:

CustID	Name	Invoices (₹)	Receipts (₹)	Balance (₹)
C1	Asha Traders	23,000	10,000	13,000
C2	Bilal Stores	12,000	12,000	0
Total		35,000	22,000	13,000

Example 4: Bank reconciliation from two tables · 3 marks · Short answerHarder board level

A cash book table shows a balance of ₹85,000. Comparing it with the bank statement table shows: cheques of ₹12,000 issued but not yet presented; cheques of ₹7,000 deposited but not yet credited; and bank charges of ₹500 debited by the bank but not yet entered in the cash book. Find the balance as per the bank statement, starting from the cash book balance. (3 marks)

Try it first, then show the solutionSolution

Start with the cash book balance ₹85,000.
Add cheques issued but not presented (the bank has not yet paid them): + 12,000.
Less cheques deposited but not credited: − 7,000; less bank charges not in the cash book: − 500.
Bank statement balance = 85,000 + 12,000 − 7,000 − 500 = ₹89,500.

Answer: Balance as per the bank statement = ₹89,500.

Example 5: Justifying a keyed design · 3 marks · Short answerHOTS / competency

A clerk stores the customer's name, city and phone number in every invoice record. A customer with 40 invoices moves to another city. Compare this design with a Customer table linked to invoices through CustID, in terms of updates required, risk of inconsistency and which report would still be easy to produce. (3 marks)

Try it first, then show the solutionSolution

Clerk's design: 40 invoice records need the new city; if one is missed, the database shows two cities for the same customer.
Keyed design: the Customer record is changed once; every invoice shows the new city through the link.
A customer-wise balance report is easy with CustID; in the first design it needs matching on names that may be spelt differently.

Answer: The keyed design needs 1 update instead of 40, prevents inconsistency, and makes customer-wise reports reliable because CustID is unique.

Where students lose marks in DBMS: Concepts, Features, Types and Business Applications

The slips examiners see most often, and what to write instead.

Mistake: Calling a row a field
Mixing up table terms.
Wrong working
Each row is a field
Right working
Each row is a record; each column is a field
Do this: Fields run down; records run across.
Usually costs: 1 mark.
Mistake: Using a name as the primary key
Names look unique.
Wrong working
Primary key: customer name
Right working
Primary key: CustID
Do this: Two customers can share a name; use a coded key.
Usually costs: 1 mark.
Mistake: Treating forms and reports as the same
Both are screens or printouts.
Wrong working
Form: printed list of debtors
Right working
Form: data entry screen; report: formatted output
Do this: Form in, report out.
Usually costs: 1 mark.
Mistake: Wrong direction in a bank reconciliation
Adding items that should be deducted.
Wrong working
85,000 + 12,000 + 7,000 + 500
Right working
85,000 + 12,000 − 7,000 − 500
Do this: Think what each item does to the bank statement balance.
Usually costs: 2 marks.

Exam tips

Draw the tables with field names and mark the primary key (PK) and foreign key (FK).
Name the relationship type and the linking field.
Give a one-line use for form, report and index.
For business examples, tie each table to an accounting record.

Practice questions on DBMS: Concepts, Features, Types and Business Applications

Write each answer on paper first. Open the hint only if you are stuck, and the answer only when you have finished.

Q1 · 1 mark · MCQBoard level
A field that uniquely identifies each record in a table is the:
(a) foreign key
(b) primary key
(c) form
(d) report
Hint
It cannot repeat.
Answer
(b) primary key
Q2 · 3 marks · Short answerBoard level
Explain the terms: (i) database design; (ii) index; (iii) report. (3 marks)
Hint
One line each.
Answer
(i) Database design: describing the structure of the parts of the database: tables, fields, keys, relationships. (ii) Index: a lookup on a field that speeds searching and sorting. (iii) Report: formatted output of selected data.
Q3 · 3 marks · Short answerHarder board level
In an asset database, Asset(AssetID, Name, Cost, Rate) holds A1 Machine ₹2,00,000 at 10% and A2 Computer ₹60,000 at 40%. For one year of straight-line depreciation on cost, state the depreciation and book value of each asset and the total book value. (3 marks)
Hint
Depreciation = Cost × Rate.
Answer
A1: depreciation 20,000; book value 1,80,000. A2: depreciation 24,000; book value 36,000. Total book value = ₹2,16,000.
Q4 · 6 marks · Long answerHarder board level
Design a database for creditors: name the tables, fields, primary and foreign keys and relationships for Supplier and Purchase and Payment. Using Supplier S1 with purchases of ₹40,000 and ₹25,000 and a payment of ₹30,000, find the balance payable. (6 marks)
Hint
Three tables, two foreign keys.
Answer
Supplier(SuppID PK, Name, City); Purchase(BillNo PK, SuppID FK, Amount); Payment(PayNo PK, SuppID FK, Amount). One supplier to many purchases and many payments. Balance payable for S1 = 40,000 + 25,000 − 30,000 = ₹35,000.
Q5 · 3 marks · Short answerHOTS / competency
A shop keeps item name and price typed on every sales record. The price of one item changes, and 150 sales records contain that item. Explain how a Product table linked by ProductCode reduces work and risk, and state what happens to old sales values if prices are looked up only from the Product table. (3 marks)
Hint
Think about history as well as updates.
Answer
With a Product table the price is changed in 1 record, not 150, and cannot be inconsistent. But if old sales look up the current price, past values would change; so the sales record must also store the price at the time of sale.

Test your recall

Answer in your head or on paper first, then open the card. Pulling an answer out of memory makes it stick far better than re-reading.

1.What is a DBMS?Show answer
Software that creates, stores, updates and retrieves a database.
2.A column of a table is called?Show answer
A field (attribute).
3.What is a foreign key?Show answer
A field holding the primary key of another table.
4.Name two DBMS business examples in the syllabus.Show answer
Debtors and creditors; bank reconciliation statement (also accounting information and asset accounting).
5.What speeds up searching on a field?Show answer
An index.

DBMS: Concepts, Features, Types and Business Applications: frequently asked questions

Which DBMS software is used in the exam?

The syllabus is software-neutral; SQL commands are the standard way to update and retrieve data.

Is a spreadsheet a database?

A spreadsheet list can act as a small database, but a DBMS gives keys, relationships, security and many users.

What are the types of DBMS?

Hierarchical, network, relational and object-oriented are the usual types; business applications mostly use relational.

What is an entity?

A person, item or event about which data is stored, with attributes as its properties.