26. In how many ways, relationships between tables are created?
Answer: There are two ways to create the relationships between the tables:
(a) Click on the Insert option and select New Relation… option in the Relation Design window.
Select the options as required.
(b) Add tables in Relation Design Window.
Drag the primary key column from one table and drop it on the key column of another table.
26. What is One to One Relationship?
Answer: In a one-to-one relationship, each record of table A can have only one matching record in table B, and each record in table B can have only one matching record in table A.
In this relationship, both tables must have primary key columns.
Example: In tables EMP and DEPT, EMP_ID in EMP table and DEPT_ID in DEPT table are the primary keys.
27. What is One to Many Relationship?
Answer: In a one-to-many relationship, a record of table A can have only one matching record in table B, but a record in table B has only one matching record in table A.
For example Teacher and Student table, one teacher record is related to many student records as one class teacher can teach many students.
In this relationship, one of the table must have primary key column.
28. What is Many to Many Relationship?
Answer: In a many-to-many relationship, a record in table A and a record in table B can have many matching records.
For example Teacher and Student table, one teacher record is related to many student records as one class teacher can teach many students.
In this relationship, one of the table must have primary key column.
29. What are the Parent table and Child table?
Answer: In a one-to-many relationship, the ‘one’ side table is called the parent table, and the ‘many’ side table is called the child table.
30. Give two examples of one-to-one relationships.
Answer: A Student has one School ID, A driver has one license, An edition of a book has one publisher, a country has one capital
31. Give two examples of one-to-many relationships.
Answer: A large company (one) and its offices (many); a teacher (one) and his students (many); a woman (one) and her children (many);
32. Give two examples of many-to-many relationships.
Answer: Many customers can buy multiple products; a doctor treats many patients and many patients are treated by many teachers;
33. Write steps to create a relationship.
Answer: To create a relationship,
(a) Click on Tools > Relationships ;
(b) It will open Add Tables dialog, Add tables;
(c) In Relation Design Window, Select the field (common) of one table, and drag and drop it to another field (common).
34. How to save the relationship?
Answer: To save the relationship,
(A) Press Ctrl + S
(B) Select File>Save,
(C) Click on Save Icon
35. How to delete a relationship?
Answer: To delete a relationship,
Right-click on the relationship line and click Delete from the menu.
** Session 3 – Perform Operations on Table Click Here
Unit 3 RDBMS Question Answers and MCQs
- Class 10 Info Tech Unit 3 RDBMS Session 1 Appreciate the Concept of Database Management System MCQs
- Class 10 Info Tech RDBMS Session 2 Create and Edit Tables Using Wizard and SQL Commands MCQs
- Class 10 Info Tech Unit 3 RDBMS Session 1 Appreciate Concept of Database Management System 50+ Question Answer
- Class 10 Info Tech Unit 3 RDBMS Session 2 – Create and Edit Tables Using Wizard & SQL Commands 50+ Question Answer
- Class 10 Info Tech Unit 3 RDBMS Session 3 – Perform Operations On Tables 50+ Question and Answer
- Class 10 Info Tech Unit 3 RDBMS Session 4 – Retrieve Data Using Query 50+ Question Answer
- Class 10 Info Tech Unit 3 RDBMS Session 5 – Create Forms and Reports using Wizard 50+ Question Answer
- Class 10 Info Tech 402 Unit 3 RDBMS Database Management System Notes Download PDF
- Structured Query Language (SQL ) in OpenOffice.org Base
- Class 10 IT 402 RDBMS – SQL Commands in OpenOffice Base Notes
