DBMS Multiple Choice Questions (MCQs) and Answers

CREATE INDEX gin_tags ON Posts USING GIN(tags)

GIN INDEX CREATE ON Posts(tags)

CREATE GIN INDEX ON Posts(tags)

INDEX GIN CREATE ON Posts USING (tags)

CREATE UNIQUE INDEX ux_name ON Employees(FirstName, LastName)

UNIQUE INDEX CREATE Employees(FirstName, LastName)

CREATE INDEX UNIQUE Employees ON (FirstName, LastName)

INDEX CREATE UNIQUE ON Employees(FirstName, LastName)

The database has been indexed incorrectly

The underlying data has significantly increased in size

A network issue is causing delayed responses

The query optimizer is malfunctioning

The new index requires additional storage space

The update operations do not use the index

Updating the table now requires updating the index as well

The index has caused a lock on the table

Rebuild the index

Update the database statistics

Increase the query timeout

Change the query's isolation level

Increased data redundancy

Simpler data management

Improved data availability and disaster recovery

Reduced data security

The process of breaking down data into smaller, manageable parts for storage

The unintended loss of data due to network issues

The division of data into different types for analysis

Segmenting and storing parts of a database at different locations based on certain criteria

Data consistency across multiple sites

Encrypting data transmitted between sites

Optimizing query performance across networks

Managing distributed database schema changes

Adding more columns to a database table

Splitting a database across different physical locations

Increasing the storage capacity of a single database server

Adding more servers or nodes to manage increased load

That the database will be immediately consistent after any transaction

That the database may temporarily have different data copies, which will become consistent over time

That consistency is not guaranteed in any form

That consistency between database copies is achieved through periodic synchronization

SELECT * FROM RemoteServer.RemoteOrders

SELECT * FROM RemoteOrders AT RemoteServer

SELECT * FROM LINKED.RemoteServer.RemoteOrders

SELECT * FROM RemoteOrders@RemoteServer

Use the sh.enableSharding("databaseName") command

Set up a shard cluster and define shard keys for collections

Implement a custom sharding algorithm

Configure replication sets for automatic sharding

ONE

QUORUM

ALL

LOCAL_QUORUM

A single overloaded server

Network latency between distributed nodes

Incorrectly configured indexes

All of the above

The transactions are accessing non-partitioned data, requiring data replication

Transactions are not being distributed correctly, necessitating a review of the partitioning strategy

Locks are not being acquired on the data, suggesting the need for explicit locking mechanisms

Partitioned data is not being synchronized properly, indicating the need for transaction coordination

By immediately synchronizing all data replicas

By using a conflict resolution mechanism such as last write wins

By reducing the number of database replicas

By avoiding updates to data

Strict schema enforcement

Support for SQL syntax

Ability to handle unstructured and semi-structured data efficiently

Primarily used for transactional data

Document store

Key-value store

Graph database

Column-family store

The process of replicating data across multiple servers for fault tolerance

Partitioning data across multiple servers to improve performance

Encrypting data at rest

Compressing data to save storage space

A data storage technique for large datasets

A programming model for processing large data sets with a parallel, distributed algorithm on a cluster

A type of NoSQL database

A data backup and recovery strategy

It guarantees immediate consistency

It never achieves consistency

It achieves consistency over time, after all updates propagate

It prioritizes availability over consistency

db.createCollection("users")

CREATE COLLECTION users

db.users.create()

mongodb.create("users")

CREATE TABLE messages (id UUID PRIMARY KEY, message text, TTL int)

CREATE TABLE messages (id UUID PRIMARY KEY, message text) WITH default_time_to_live=3600

ALTER TABLE messages ADD TTL (message, 3600)

None of the above

SET user:100 "John Doe" EXPIRE 600

SET user:100 "John Doe" TTL 600

SET user:100 "John Doe" WITH EXPIRY 600

SETEX user:100 600 "John Doe"

Adding an index on the frequently accessed field

Increasing the memory allocated to the database

Splitting the database into smaller, separate databases

Replicating the database for read-heavy workloads

Manually transferring data between nodes

Rebooting the cluster

Updating the database schema

Triggering a rebalance operation across the cluster

By writing all data to a single key

By using sequential keys for data insertion

By sharding data across keys using a hash of the timestamp

By increasing the write throughput limits on the database

A database optimized for transaction processing

A collection of tools for web data mining

A centralized repository for integrating data from various sources

A type of NoSQL database

The process of organizing data into categories for efficient storage

Dividing a database into smaller, manageable parts

The task of predicting the class label of given input data

The restructuring of a data warehouse

Data warehousing focuses on capturing data from diverse sources, whereas databases focus on storing real-time transactional data

Data warehousing is optimized for read-intensive operations, whereas databases are optimized for write-intensive operations

Data warehouses primarily use SQL for querying, whereas databases use NoSQL

Data warehouses store unstructured data, whereas databases store structured data