2026/2027 | HIGH-YIELD QUESTIONS & ANSWERS | KEY CONCEPTS | EXAM-STYLE
PRACTICE TEST | DETAILED RATIONALES | LATEST UPDATE
1. What SQL statement is commonly used to create an index in the Physical
Design Phase of database design?
ALTER TABLE
SELECT * FROM
CREATE INDEX
DROP INDEX
2. What operation does the modulo function perform in the context of hashing?
Encrypting data
Determining the bucket number
Generating a hash key
Sorting data entries
3. Describe how the Entity-Relationship Model aids in the database design
process.
It outlines the SQL commands needed for data manipulation.
It provides a high-level overview of data requirements without
focusing on implementation details.
It details the security measures for database access.
It specifies the physical storage of data in the database.
4. What is the purpose of an aggregate function in SQL?
To update multiple rows in a database
, To process values from a set of rows and return a summary value
To delete a set of rows based on a condition
To select individual rows from a table
5. A has a name and a data type.
table
cell
column
row
6. Describe how the IN operator enhances the functionality of a SQL WHERE
clause.
The IN operator is used to join tables in SQL queries.
The IN operator only works with numeric values in SQL.
The IN operator allows for checking multiple possible values for a
single column, making queries more concise.
The IN operator restricts results to a single value, simplifying the
query.
7. What is the main goal of normalization in database design?
Enhancing query speed
Simplifying data types
Increasing data duplication
Eliminating redundancy
,8. What is the primary purpose of a database application?
To perform data analysis and reporting.
To help business users interact with database systems.
To store data in a structured format.
To manage user access and permissions.
9. Describe what an attribute instance represents in the context of a database.
An attribute instance is the name of a database column.
An attribute instance is a type of database query.
An attribute instance represents a specific value associated with a
particular attribute in a database record.
An attribute instance refers to the structure of a database table.
10. What is a primary key?
a specific type of field in a relational database that can identify each
unique record independently of any other data.
the column or columns that contain values that uniquely identify
each row in a table.
a unique key for an entity in the client's business or for an object in
the database.
a combination of two or more columns in a table that can be used to
uniquely identify each row in the table.
11. What is an entity-relationship model primarily used for in database design?
Optimizing the performance of database queries
Storing and retrieving data from a database
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12. What is the primary purpose of a RIGHTJOIN in SQL?
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j 2 To select only the rows that match in both tables.
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j 2 Toselectallrowsfromtherighttableandonlymatchingrowsfrom the
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j 2 To select all rows from both tables regardless of matches.
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j 2 To select all rows from the left table and only matching rows from the
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13. Describe howAggregate Functions can be utilized in SQLto summarize
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data.
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j 2 Aggregate Functions allow users to join multiple tables together. j 2 j2 j 2 j2 j2 j 2 j2 j2
j 2 Aggregate Functions are primarily used for data entry in databases.
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j 2 Aggregate Functions are used to filter records based on specific criteria.
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14. Describe the significance of the CASCADE option in maintaining referential
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integrity within a database.
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j 2 The CASCADE option allows for the creation of new foreign keys.
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j 2 The CASCADE option prevents any changes to primary keys.
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j 2 TheCASCADEoptionensuresthatchangestoprimarykeysare
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automaticallyreflected inforeignkeys, maintaining referential
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