Trắc Nghiệm Khoá SQL Server

SQL Server/MySQL

Trắc Nghiệm Khoá SQL Server - Phần 1

Câu hỏi 1: What does a database primarily consist of according to the RDBMS concepts?

A: Unrelated files
B: Related data items called records
C: Hardware components
D: Operating system settings

Đáp án: B

Câu hỏi 2: What is the result when data is gathered and intelligently interpreted?

A: Information
B: Storage
C: Metadata
D: Network

Đáp án: A

Câu hỏi 3: In a file-based system, what were files of archived data called?

A: Columns
B: Tables
C: Fields
D: Relationships

Đáp án: B

Câu hỏi 4: What does DBMS stand for?

A: Data Backup Management System
B: Database Management System
C: Data Binding Management System
D: Database Manipulation System

Đáp án: B

Câu hỏi 5: Which data model is best used for simple databases to store data like roll numbers and names?

A: Network Data Model
B: Relational Data Model
C: Flat-File Data Model
D: Hierarchical Data Model

Đáp án: C

Câu hỏi 6: In which data model are relationships thought of in terms of children and parents?

A: Relational Data Model
B: Flat-File Data Model
C: Object-Oriented Model
D: Hierarchical Data Model

Đáp án: D

Câu hỏi 7: What is a row called in a Relational Data Model?

A: Tuple
B: Attribute
C: Domain
D: Cardinality

Đáp án: A

Câu hỏi 8: What is the number of attributes in a relation called?

A: Cardinality
B: Tuple
C: Degree
D: Domain

Đáp án: C

Câu hỏi 9: How are tables related to one another in a Relational Data Model?

A: Through physical links
B: Through common columns
C: Through network schemas
D: Through hierarchy trees

Đáp án: B

Câu hỏi 10: Which of the following is an advantage of an RDBMS over a DBMS?

A: It is less secure
B: It uses physical links
C: It is a single user system
D: It enforces tabular relationships to manage business rules

Đáp án: D

Câu hỏi 11: What is defined as a group of conceptual tools that describes data, its relationships, and semantics?

A: Data model
B: Data isolation
C: Normalization
D: Record

Đáp án: A

Câu hỏi 12: Which component of the E-R model represents a real-world object that exists physically?

A: Relationship
B: Attribute
C: Entity
D: Cardinality

Đáp án: C

Câu hỏi 13: What type of relationship exists between entities of the same entity set?

A: Binary relationship
B: Self-relationship
C: Ternary relationship
D: Weak relationship

Đáp án: B

Câu hỏi 14: What is a primary key in an E-R model?

A: An attribute that uniquely defines an entity
B: A relationship between two entities
C: A collection of similar entities
D: A weak entity set

Đáp án: A

Câu hỏi 15: What are entity sets that do not have enough attributes to establish a primary key called?

A: Strong entity sets
B: Multi-valued sets
C: Derived sets
D: Weak entity sets

Đáp án: D

Câu hỏi 16: Which normal form requires that all key attributes be identified and table columns have atomic values?

A: First Normal Form
B: Second Normal Form
C: Third Normal Form
D: Boyce-Codd Normal Form

Đáp án: A

Câu hỏi 17: What anomaly occurs when data is repeated more than once in a table?

A: Insertion anomaly
B: Repetition anomaly
C: Deletion anomaly
D: Updating anomaly

Đáp án: B

Câu hỏi 18: Which relational operator is used to extract data that satisfies a given condition?

A: PROJECT
B: PRODUCT
C: SELECT
D: DIVIDE

Đáp án: C

Câu hỏi 19: Which operator collects data from different tables and presents a unified version of the complete data?

A: UNION
B: INTERSECT
C: DIFFERENCE
D: JOIN

Đáp án: A

Câu hỏi 20: Which relational operator generates data that holds true in all the tables it is applied on?

A: PRODUCT
B: UNION
C: DIFFERENCE
D: INTERSECT

Đáp án: D

Câu hỏi 21: Which of the following is an RDBMS developed by Microsoft?

A: Oracle
B: MySQL
C: PostgreSQL
D: SQL Server

Đáp án: D

Câu hỏi 22: Which component of SQL Server basic architecture includes Memory, Configuration files, and CPU?

A: Tools
B: Services
C: Instances
D: Extensions

Đáp án: C

Câu hỏi 23: Which SQL Server service is used for moving, copying, and transforming data?

A: SQL Server Reporting Services
B: SQL Server Integration Services
C: SQL Server Analysis Services
D: SQL Server Master Data Services

Đáp án: B

Câu hỏi 24: Which SQL Server tool is a command-line tool that can be used in place of SSMS?

A: SQL Server Profiler
B: SQL Server Configuration Manager
C: SQLCMD
D: SSDT

Đáp án: C

Câu hỏi 25: Which SQL Server edition uses a maximum of 4 sockets or 24 cores of CPU and up to 128 GB of RAM?

A: Enterprise
B: Standard
C: Express
D: Developer

Đáp án: B

Câu hỏi 26: What feature allows the query optimizer to consider parameter values to generate the most efficient execution plan?

A: Object Storage Integration
B: Parameter Sensitive Plan Optimization
C: Query Store
D: Azure Synapse Link

Đáp án: B

Câu hỏi 27: Which application is a GUI-based tool used to connect to SQL Server instances and manage databases?

A: SQLCMD
B: SSMS
C: SQL Server Profiler
D: DB-Library

Đáp án: B

Câu hỏi 28: Which type of databases store crucial information related to the configuration and metadata of the system?

A: User-defined Databases
B: Sample Databases
C: System Databases
D: Network Databases

Đáp án: C

Câu hỏi 29: What is AdventureWorks2022?

A: A System Database
B: A Sample Database
C: A SQL Server Tool
D: A User-defined Database

Đáp án: B

Câu hỏi 30: What file extension is used to store script files in SQL Server 2022?

A: .txt
B: .mdf
C: .ldf
D: .sql

Đáp án: D

Câu hỏi 31: Which language is Microsoft's implementation of the standard SQL?

A: MySQL
B: Transact-SQL (T-SQL)
C: PL/SQL
D: PostgreSQL

Đáp án: B

Câu hỏi 32: Which category of statements is used to select, insert, update, or delete data?

A: Data Definition Language (DDL)
B: Data Manipulation Language (DML)
C: Data Control Language (DCL)
D: Data Query Language (DQL)

Đáp án: B

Câu hỏi 33: Which DCL statement is used to secure the database by restricting permissions?

A: GRANT
B: REVOKE
C: DENY
D: All of the above

Đáp án: D

Câu hỏi 34: Which exact numeric data type occupies 4 bytes of memory and holds integer values?

A: tinyint
B: smallint
C: int
D: bigint

Đáp án: C

Câu hỏi 35: Which data type stores variable-length Unicode character data?

A: char
B: varchar
C: nchar
D: nvarchar

Đáp án: D

Câu hỏi 36: Which predicate is used to match characters against a specified pattern?

A: IN
B: BETWEEN
C: LIKE
D: CONTAINS

Đáp án: C

Câu hỏi 37: Which type of function in Transact-SQL takes a single input and returns a single value?

A: Rowset function
B: Ranking function
C: Aggregate function
D: Scalar function

Đáp án: D

Câu hỏi 38: What character is used to prefix a local variable name in Transact-SQL?

A: #
B: @@
C: @
D: $

Đáp án: C

Câu hỏi 39: Which control-of-flow statement provides branching control based on a logical test?

A: WHILE
B: TRY...CATCH
C: IF...ELSE
D: BEGIN...END

Đáp án: C

Câu hỏi 40: In the logical order of operations for a SELECT statement, which clause is evaluated first?

A: SELECT
B: FROM
C: WHERE
D: ORDER BY

Đáp án: B

Câu hỏi 41: Which API includes complete functionality for administering SQL Server in applications?

A: SSMS Administration utilities
B: SQL-SMO API
C: ADO.NET
D: ODBC

Đáp án: B

Câu hỏi 42: What extension is used for the primary database file in SQL Server?

A: .ldf
B: .ndf
C: .mdf
D: .dbf

Đáp án: C

Câu hỏi 43: Which file keeps track of changes that have been made in the database?

A: Master Database File
B: Log Database File
C: Secondary Database File
D: System Database File

Đáp án: B

Câu hỏi 44: Which statement is used to change the size or filegroups of a database?

A: CREATE DATABASE
B: DROP DATABASE
C: ALTER DATABASE
D: UPDATE DATABASE

Đáp án: C

Câu hỏi 45: Which system procedure is used to change the ownership of a user-defined database?

A: sp_changeowner
B: sp_changedbowner
C: sp_updateowner
D: sp_modifydb

Đáp án: B

Câu hỏi 46: Which database option controls the recovery models of a database?

A: Automatic options
B: Cursor options
C: Recovery options
D: State options

Đáp án: C

Câu hỏi 47: What is the maximum number of filegroups that can be created for each database?

A: 1,024
B: 8,000
C: 32,767
D: 65,535

Đáp án: C

Câu hỏi 48: Which filegroup is the default filegroup in SQL Server?

A: USER-DEFINED
B: PRIMARY
C: SECONDARY
D: LOG

Đáp án: B

Câu hỏi 49: Which agent monitors the transaction log of each database configured for replications?

A: Snapshot Agent
B: Merge Agent
C: Log Reader Agent
D: Distribution Agent

Đáp án: C

Câu hỏi 50: What feature provides a read-only, static view of a SQL Server database?

A: Database snapshot
B: Filegroup
C: Transaction log
D: Primary key

Đáp án: A

Câu hỏi 51: Which advanced data type represents data in a Euclidean (flat) coordinate system?

A: geography
B: geometry
C: hierarchyid
D: xml

Đáp án: B

Câu hỏi 52: Which data type returns automatically generated, unique binary numbers within a database?

A: rowversion
B: xml
C: uniqueidentifier
D: timestamp

Đáp án: A

Câu hỏi 53: Which statement is used to remove a table definition and all its associated objects?

A: ALTER TABLE
B: DROP TABLE
C: DELETE TABLE
D: TRUNCATE TABLE

Đáp án: B

Câu hỏi 54: Which statement adds a new row to a table?

A: UPDATE
B: ADD
C: INSERT
D: CREATE

Đáp án: C

Câu hỏi 55: In SQL Server, what does a null value in a column mean?

A: The value is zero
B: The value is a blank space
C: The value is unknown or has not been set
D: The value is infinite

Đáp án: C

Câu hỏi 56: What keyword indicates that null values are not allowed in a column?

A: NULL
B: NOT NULL
C: DEFAULT
D: UNIQUE

Đáp án: B

Câu hỏi 57: Which property is used to create columns that contain auto-generated sequential values?

A: DEFAULT
B: UNIQUE
C: CHECK
D: IDENTITY

Đáp án: D

Câu hỏi 58: What is the identity number for the first row inserted into a table called?

A: Increment
B: Sequence
C: Seed value
D: Default value

Đáp án: C

Câu hỏi 59: Which constraint enforces referential integrity by pointing to a primary key in another table?

A: PRIMARY KEY
B: UNIQUE
C: CHECK
D: FOREIGN KEY

Đáp án: D

Câu hỏi 60: Which constraint limits the values that can be placed in a column using a search condition?

A: CHECK
B: DEFAULT
C: FOREIGN KEY
D: NOT NULL

Đáp án: A

Câu hỏi 61: What is Microsoft Azure SQL Database commonly known as?

A: SQL Server Cloud
B: Azure SQL
C: SQL Azure Service
D: Windows Database

Đáp án: B

Câu hỏi 62: Which Azure SQL service is best suited for migrating mission-critical workloads requiring OS-level access?

A: Azure SQL Database
B: Azure SQL Managed Instance
C: Azure SQL Edge
D: SQL Server on Azure Virtual Machines

Đáp án: D

Câu hỏi 63: Which Azure SQL product is a small-footprint, edge-optimized SQL database engine with built-in AI?

A: Azure SQL Edge
B: Azure SQL Database
C: Azure SQL Managed Instance
D: SQL Server on Azure Virtual Machines

Đáp án: A

Câu hỏi 64: Which protocol is used by applications to retrieve data from Azure SQL?

A: HTTP
B: Tabular Data Stream (TDS)
C: FTP
D: OLE DB

Đáp án: B

Câu hỏi 65: In Azure SQL Architecture, which layer acts as a doorway between platform and client layers?

A: Infrastructure Layer
B: Platform Layer
C: Service Layer
D: Client Layer

Đáp án: C

Câu hỏi 66: Which layer includes systems that host the actual Azure SQL Server in the data center?

A: Client Layer
B: Platform Layer
C: Infrastructure Layer
D: Service Layer

Đáp án: B

Câu hỏi 67: Compared to AWS RDS, Azure SQL is stated to be:

A: Slower and more expensive
B: 3.6 times faster and 86% less expensive
C: 2 times faster and equally expensive
D: Only available for on-premises applications

Đáp án: B

Câu hỏi 68: Which SQL Server feature is NOT required in Azure SQL because data is on the cloud platform?

A: SELECT statement
B: Authentication
C: Backup and restore
D: Table creation

Đáp án: C

Câu hỏi 69: Which authentication method does Azure SQL solely support?

A: Windows Authentication
B: SQL Server Authentication
C: Biometric Authentication
D: Multi-factor Authentication

Đáp án: B

Câu hỏi 70: Which Transact-SQL statement cannot be used to switch between databases in Azure SQL?

A: SELECT
B: UPDATE
C: USE
D: ALTER

Đáp án: C

Câu hỏi 71: Which character is used as a shorthand in the SELECT statement to retrieve all columns?

A: #
B: @
C: %
D: *

Đáp án: D

Câu hỏi 72: Which clause is used with SELECT to conditionally filter the records retrieved?

A: GROUP BY
B: ORDER BY
C: WHERE
D: HAVING

Đáp án: C

Câu hỏi 73: Which keyword prevents the retrieval of duplicate records in a SELECT query?

A: TOP
B: DISTINCT
C: UNIQUE
D: PERCENT

Đáp án: B

Câu hỏi 74: Which clause creates a new table and inserts the retrieved rows into it?

A: INSERT INTO
B: SELECT INTO
C: CREATE INTO
D: UPDATE INTO

Đáp án: B

Câu hỏi 75: What wildcard character is used to display a single character in a LIKE pattern?

A: % (percent)
B: _ (underscore)
C: *
D: [^]

Đáp án: B

Câu hỏi 76: Which clause partitions the resultset into one or more subsets?

A: ORDER BY
B: GROUP BY
C: HAVING
D: WHERE

Đáp án: B

Câu hỏi 77: If a grouping column contains more than one NULL value, how does GROUP BY treat them?

A: Ignores them
B: Puts them into separate groups
C: Puts them into a single row
D: Throws an error

Đáp án: C

Câu hỏi 78: Which keyword can be used with GROUP BY to include all groups, even those not meeting search conditions?

A: ALL
B: ANY
C: SOME
D: DISTINCT

Đáp án: A

Câu hỏi 79: Which clause specifies a search condition specifically for a group?

A: WHERE
B: FROM
C: HAVING
D: ORDER BY

Đáp án: C

Câu hỏi 80: What is an XML instance that has a schema associated with it called?

A: Untyped XML
B: Typed XML
C: Parsed XML
D: Native XML

Đáp án: B

Câu hỏi 81: Which aggregate operator produces a super-aggregate row for all groups generated by the GROUP BY clause?

A: ROLLUP
B: CUBE
C: PIVOT
D: UNPIVOT

Đáp án: B

Câu hỏi 82: Which operator generates a resultset that shows groups arranged in a hierarchical order?

A: CUBE
B: UNION
C: ROLLUP
D: INTERSECT

Đáp án: C

Câu hỏi 83: Which aggregate function ignores NULL values and calculates the average of numeric values?

A: SUM
B: MIN
C: AVG
D: MAX

Đáp án: C

Câu hỏi 84: Which spatial aggregate method returns the bounding area for a set of geometry or geography objects?

A: STUnion
B: STIntersection
C: Envelope Aggregate
D: Convex Hull Aggregate

Đáp án: C

Câu hỏi 85: What is a subquery that takes parameters from its parent query called?

A: Scalar subquery
B: Multi-valued subquery
C: Nested subquery
D: Correlated subquery

Đáp án: D

Câu hỏi 86: Which type of join returns all rows from at least one of the tables specified, even if there are no matches?

A: Inner Join
B: Self-Join
C: Outer Join
D: Equi Join

Đáp án: C

Câu hỏi 87: Which statement performs insert, update, or delete operations on a target table based on the results of a join with a source table?

A: SET
B: MERGE
C: SELECT INTO
D: UNION

Đáp án: B

Câu hỏi 88: Which SET operator returns distinct rows that are common to both query statements?

A: UNION
B: EXCEPT
C: INTERSECT
D: JOIN

Đáp án: C

Câu hỏi 89: Which SET operator removes all rows from the left query's resultset that match rows from the right query?

A: EXCEPT
B: INTERSECT
C: UNION
D: MERGE

Đáp án: A

Câu hỏi 90: Which operator transforms data from a row-based orientation to a column-based orientation?

A: UNPIVOT
B: PIVOT
C: CUBE
D: ROLLUP

Đáp án: B

Câu hỏi 91: What is a virtual table made up of selected columns from one or more base tables called?

A: Stored Procedure
B: View
C: Function
D: Trigger

Đáp án: B

Câu hỏi 92: What is the maximum number of columns a view can have?

A: 256
B: 512
C: 1024
D: 2048

Đáp án: C

Câu hỏi 93: Which view option ensures that all updates satisfy the conditions mentioned in the view definition?

A: SCHEMABINDING
B: CHECK OPTION
C: ENCRYPTION
D: VIEW_METADATA

Đáp án: B

Câu hỏi 94: Which option binds a view to the schema of its underlying tables?

A: SCHEMABINDING
B: CHECK OPTION
C: WITH TIES
D: NOCOUNT

Đáp án: A

Câu hỏi 95: Which stored procedure is used to update the metadata for a view if the underlying tables are changed?

A: sp_helptext
B: sp_changedbowner
C: sp_refreshview
D: sp_tables

Đáp án: C

Câu hỏi 96: What is a pre-compiled group of Transact-SQL statements that act as a single block of code called?

A: View
B: Stored Procedure
C: Table Expression
D: Batch

Đáp án: B

Câu hỏi 97: Which prefix is used for extended stored procedures in SQL Server?

A: sp_
B: fn_
C: xp_
D: tr_

Đáp án: C

Câu hỏi 98: What type of stored procedure is visible only to the user that created it and is dropped at the end of the session?

A: System Stored Procedure
B: Extended Stored Procedure
C: Local Temporary Procedure
D: Global Temporary Procedure

Đáp án: C

Câu hỏi 99: What is the maximum level of nesting supported by SQL Server 2022 for stored procedures?

A: 8
B: 16
C: 32
D: 64

Đáp án: C

Câu hỏi 100: What type of view provides an internal, system table independent view of the SQL Server metadata?

A: Dynamic Management View
B: Information Schema View
C: Catalog View
D: System View

Đáp án: B