Databases

விளையாடிக் கற்றுக்கொள்ளுங்கள்

ஆற்றல் சம்பாதிக்க இந்த கேள்விகளுக்குப் பதிலளியுங்கள், பின்னர் மீன் பிடித்து ஆராயுங்கள். கணக்கு தேவையில்லை.

ஆசிரியர்களுக்கு: Databases (Computer Science, CIE)-க்கான தயாரான பாட ஸ்லைடுகள், திருப்புதல் குறிப்புகள் — உங்கள் பாடத்தில் அவற்றைப் பயன்படுத்தவும், அல்லது மாணவர்கள் நேரலை விளையாட்டாக விளையாடும் ஊடாடும் வகுப்பு செயல்பாடாக தலைப்பை இயக்கவும்.

பாட குறிப்புகள்

What is a Database?

A database is an organised collection of data.
It consists of one or more tables made up of fields and records.
Databases allow easy storage, retrieval, and management of information.
They are stored on secondary storage and often on remote servers for multi-user access.
Data can be sorted and searched efficiently, and databases are more secure than text files.

Fields & Records

A field is one piece of information relating to one person/item/object; represented as a column.
A record is a collection of fields relating to one person/item/object; represented as a row.
Example: In a student table, fields include StudentID, FirstName, LastName; each row is a record.

Text Files vs Databases

Text files are useful for small amounts of data; stored on secondary storage and read into a program.
Each entry is stored on a new line or separated by a delimiter (e.g., comma).
It can be difficult to know where a record begins and ends in a text file.
Databases provide better structure, security, and efficiency for large data.

Data Types

A data type defines the type of data held in a field, set when designing a table.
Common data types: Integer (whole number), Real (decimal), Text/alphanumeric, Character (single), Date/Time, Boolean (true/false).
Example: In a cars table, car_id is Integer, make is Text, price is Real.

Validation Checks

Validation rules control what data can be entered into a field.
Length check: ensures a fixed number of characters (e.g., phone number 11 digits).
Format check: ensures data matches a pattern (e.g., two letters + five numbers).
Range check: ensures a number is within a range (e.g., age 0–40).
Presence check: ensures a field cannot be left blank.
Type check: ensures data is of the correct data type (e.g., date field cannot have text).
Check digit: a digit added to a number to verify accuracy using an algorithm.

Primary Keys

A primary key is a unique field that identifies each record in a table.
It must be unique for every record and cannot be null.
Examples: CustomerID, StudentID, Car Registration, ProductID.
Primary keys are often ID numbers (e.g., MemberID in a Members table).

Key Database Terminology

Table: a collection of records with a similar structure.
Record: a group of related fields representing one data entry (a row).
Field: a single piece of data in a record (a column).
Data type: the type of data held in a field.
Primary key: a unique identifier for each record, usually an ID number.

ஸ்லைடுகள்

Step through every slide for this topic — plus flashcards and revision notes — with a free account.

பதிவு செய்க — இலவசம்உள்நுழைக

பயிற்சி கேள்விகள்

இலவச முன்னோட்டம் — 60-இல் 8 கேள்விகள். அனைத்தையும் பார்க்க பதிவு செய்யவும்.

1.What is a database?
Easy
- AAn organised collection of data
- BA collection of text files
- CA single table of data
- DA program for editing data
2.In a database table, a field is represented by a:
Easy
- ARow
- BColumn
- CRecord
- DTable
3.In a database table, a record is represented by a:
Easy
- AColumn
- BField
- CRow
- DPrimary key
4.Which of the following is the most suitable primary key for a table storing information about books in a library?
Easy
- AAuthor
- BTitle
- CISBN
- DPublisher
5.Which validation check would ensure that a phone number field contains exactly 11 digits?
Easy
- ARange check
- BLength check
- CFormat check
- DPresence check
6.A product code must be two letters followed by five numbers. Which validation check should be applied?
Medium
- ALength check
- BRange check
- CFormat check
- DType check
7.Which data type would be most appropriate for a field storing a person's date of birth?
Easy
- AInteger
- BText
- CDate/Time
- DBoolean
8.A field is defined as 'Boolean'. What type of values can it store?
Easy
- AWhole numbers only
- BDecimal numbers
- CTrue or false values
- DSingle characters

மேலும் கேள்விகள்

9.Which validation check would be used to ensure that a field for 'age of a dog' only accepts numbers between 0 and 40?
Easy
- ALength check
- BRange check
- CType check
- DPresence check
10.A table 'Students' has fields: StudentID (integer), FirstName (text), LastName (text), DateOfBirth (date), Email (text). Which field is the most suitable primary key?
Easy
- AFirstName
- BLastName
- CStudentID
- DEmail
11.Which of the following is NOT a valid advantage of using a database over a text file?
Medium
- AEasier to search and sort data
- BMore secure
- CRequires less storage space
- DAllows multiple users to access data simultaneously
12.A check digit is used to verify the accuracy of numbers such as credit card numbers. What is a check digit?
Medium
- AA digit that is always zero
- BA digit added to the end of a number calculated from the other digits
- CA digit that indicates the length of the number
- DA digit that is randomly generated
13.A database table contains the following fields: ProductID, ProductName, Price, QuantityInStock. How many records are in the table if it contains data for 10 different products?
Easy
- A10
- B4
- C40
- D1
14.A database table 'Students' has fields: StudentID (integer), FirstName (text), LastName (text), DateOfBirth (date), Email (text). Which field would be the most suitable primary key?
Easy
- AStudentID
- BFirstName
- CEmail
- DDateOfBirth
15.A database table 'Orders' has fields: OrderID, CustomerID, OrderDate, TotalAmount. Which of the following is the most suitable primary key?
Easy
- AOrderID
- BCustomerID
- COrderDate
- DTotalAmount
16.A field in a database is defined as 'Boolean'. What values can it store?
Easy
- ATrue or False
- BYes or No
- C0 or 1
- DAll of the above
17.A table 'Books' has fields: BookID (primary key), Title, Author, ISBN, YearPublished. How many fields does the table have?
Easy
- A5
- B4
- C3
- D1
18.A database table 'Students' has fields: StudentID (integer), FirstName (text), LastName (text), DateOfBirth (date), Email (text). How many fields does the table have?
Easy
- A5
- B4
- C6
- D3
19.Which of the following best describes a database?
Easy
- AAn organised collection of data
- BA single file of unorganised text
- CA type of computer hardware
- DA programming language
20.In a database table, what does a row represent?
Easy
- AA record
- BA field
- CA primary key
- DA data type
21.Which data type would be most appropriate for a field storing a person's height in metres?
Easy
- AReal
- BInteger
- CText
- DBoolean
22.Which of the following is the most suitable primary key for a table storing information about cars?
Easy
- ARegistration number
- BColour
- CMake
- DYear of manufacture
23.A validation check ensures that a field named 'Postcode' must contain exactly 7 characters. What type of validation is this?
Easy
- ALength check
- BFormat check
- CRange check
- DPresence check
24.A database table 'Students' has fields: StudentID (integer), FirstName (text), LastName (text), DateOfBirth (date), Email (text). Which field is the most suitable primary key?
Easy
- AStudentID
- BFirstName
- CEmail
- DDateOfBirth
25.A database table 'Orders' has fields: OrderID, CustomerID, OrderDate, TotalAmount. How many fields does the table have?
Easy
- A4
- B1
- C3
- D5
26.A database table 'Products' has fields: ProductID (integer), ProductName (text), Price (real), QuantityInStock (integer). How many fields does the table have?
Easy
- A3
- B4
- C5
- D6
27.A database table 'Employees' has fields: EmployeeID, FirstName, LastName, Department, Salary. Which field is most suitable as a primary key?
Easy
- AFirstName
- BDepartment
- CSalary
- DEmployeeID
28.Which validation check would ensure that a field for 'age of a dog' only accepts numbers between 0 and 40?
Easy
- ALength check
- BFormat check
- CRange check
- DPresence check
29.A database table 'Products' has fields: ProductID (integer), ProductName (text), Price (real), QuantityInStock (integer). Which of the following is the most suitable primary key?
Easy
- AProductID
- BProductName
- CPrice
- DQuantityInStock
30.A database table 'Students' contains 6 fields and 30 records. How many items of data are stored in the table?
Easy
- A180
- B36
- C30
- D6
31.A database table 'Products' has fields: ProductID (integer), ProductName (text), Price (real), QuantityInStock (integer). Which field should be defined as a primary key?
Easy
- AProductID
- BProductName
- CPrice
- DQuantityInStock
32.A database table 'Employees' has fields: EmployeeID, FirstName, LastName, Department, Salary. Which of the following would be the most suitable primary key?
Easy
- AEmployeeID
- BFirstName
- CDepartment
- DSalary
33.Which validation check would ensure that a 'Postcode' field contains exactly 7 characters?
Easy
- ALength check
- BFormat check
- CRange check
- DPresence check
34.A database table 'Orders' has fields: OrderID, CustomerID, OrderDate, TotalAmount. Which field is the most suitable primary key?
Easy
- AOrderID
- BCustomerID
- COrderDate
- DTotalAmount
35.A validation rule for a 'DateOfBirth' field ensures only dates before 2006 are accepted. What type of validation is this?
Easy
- ARange check
- BFormat check
- CLength check
- DPresence check
36.Which of the following is a valid advantage of using a database over a text file?
Medium
- AData can be searched and sorted efficiently
- BData is stored in secondary storage
- CData can be read by a program
- DData is stored in a human-readable format
37.A database table 'Books' has fields: BookID (primary key), Title, Author, ISBN, YearPublished. How many fields does the table have?
Easy
- A5
- B4
- C3
- D6
38.A field is defined as 'Boolean'. What values can it store?
Easy
- ATrue or False
- BYes or No
- C0 or 1
- DAll of the above
39.Which of the following is the most suitable data type for a field storing a person's height in metres?
Easy
- AReal
- BInteger
- CText
- DBoolean
40.Which of the following is the correct definition of a field in a database table?
Easy
- AA row in a table representing one record
- BA column in a table representing one piece of information about each record
- CA collection of related tables
- DA unique identifier for each record
41.A primary key must be a unique value for each record in a table.
Easy
True or false?
42.Which of the following are advantages of using a database over a text file? (Select all that apply)
Medium
- AEasier to sort and search data
- BMore secure than text files
- CRequires less storage space
- DAllows multiple users to access data simultaneously
- ESimpler to set up for small amounts of data
43.Match each validation check type to its description.
Medium
- Length check
- Range check
- Presence check
- Checks that a field is not left blank
- Checks the number of characters entered
- Checks that a value is within a specified range
44.Arrange the following steps in the order they occur when using a check digit to verify a number:
Medium
- Calculate the check digit using the algorithm on the rest of the digits
- Compare the calculated check digit with the one provided
- Re-enter the number including the check digit
- Apply the same algorithm to the re-entered number
45.Match each database term to its correct definition.
Medium
- Field
- Record
- Primary key
- Data type
- A single piece of data in a record
- A group of related fields representing one data entry
- A unique identifier for each record in a table
- The type of data held in a field
46.Arrange the following steps in the correct order when using a check digit to verify a number.
Medium
- Calculate the check digit using an algorithm on the original digits
- Compare the calculated check digit with the one provided
- Add the check digit to the end of the number
- If they match, the number is valid; otherwise, it is incorrect
47.A primary key must contain unique values for each record in a table.
Easy
True or false?
48.A database table 'Books' has fields: BookID (integer), Title (text), Author (text), ISBN (text), YearPublished (integer). How many fields does the table have?
Easy
- A4
- B5
- C6
- D3
49.A database table 'Sales' contains the following data: SaleID (integer), Product (text), Quantity (integer), Price (real). The table has 8 records. How many fields does the table have?
Easy
- A3
- B4
- C5
- D8
50.Complete the sentence:
Easy
A database is an organised collection of ____.
51.State one reason why a database is more secure than a text file.
Easy
52.Complete the sentence: In a database table, a ___ is represented by a column, and a ___ is represented by a row.
Easy
In a database table, a ____ is represented by a column, and a ____ is represented by a row.
53.A database table 'Students' contains 8 fields and 25 records. How many items of data are stored in the table?
Easy
54.A database table 'Students' has 5 fields and 20 records. How many items of data are stored in the table?
Easy
55.Complete the sentence using the correct terms.
Easy
In a database table, a ____ is represented by a column, and a ____ is represented by a row.
56.Describe two validation checks that could be used to check data being inputted into a table that stores student grades. The table has fields: StudentID, FirstName, LastName, MarkSubmitted (Y/N), Percentage.
Medium
57.A database table 'Orders' has fields: OrderID, CustomerID, OrderDate, TotalAmount. Describe two validation checks that could be applied to the TotalAmount field.
Medium
58.A database table 'Orders' has fields: OrderID (integer), CustomerName (text), OrderDate (date), Amount (real). Describe two validation checks that could be applied to the Amount field.
Medium
59.A database table 'Students' contains 8 fields and 25 records. How many items of data are stored in the table?
Easy
- A220
- B240
- C180
- D200
60.A database table 'Students' has 5 fields and 20 records. How many items of data are stored in the table?
Easy
- A100
- B120
- C110
- D90

Unlock all 60 questions & more

இந்த தலைப்பிற்கான ஒவ்வொரு கேள்வியையும், ஸ்லைடுகளையும், ஃப்ளாஷ் கார்டுகளையும் மற்றும் திருப்புதல் குறிப்புகளையும் பார்க்க இலவச கணக்கை உருவாக்கவும்.

பதிவு செய்க — இலவசம்உள்நுழைக

முந்தைய தேர்வுகள்

இந்த தலைப்பிற்கான முந்தைய தேர்வு பயிற்சி விரைவில் வருகிறது.

விரைவில் வருகிறது