Postgres Quiz Archive

You have 200 seconds to answer 20 Random questions so think fast!

You will need to score 80% or over to pass!

Created by

Paul Sammy

PostgreSQL 14 Internals Chapter 1

A quiz to test the knowledge of those reading and learning from Postgres 14 Internals book by Egor Rogov, covering topics in Chapter 1.

1 / 20

Users should not modify the template0 database

True

False

2 / 20

What is the purpose of the public schema?

schema used for heterogeneous replication

no such schema

default schema for user objects

restricted schema for postgres internal usage only

3 / 20

Which of the below objects can be referred to as relations?

choose 3

tables

sequences

indexes

triggers

4 / 20

What is the purpose of autovacuum?

Removes stale data from tables and indexes

Deletes old logs and traces on disk

Performs a backup of WAL logs

Rebuilds indexes with b level greater than 2

5 / 20

A schema can belong to more than one database?

False

True

6 / 20

How many files or forks on disk will a 10Mb table with no index have?

7 / 20

What is the purpose of the template0 database?

No such database

Useful for Postgres support Services to debug issues

Useful for restoring data from a logical backup or creating a database with a different encoding

Useful for creating development schemas

8 / 20

Which of below are predefined schemas?

choose 2

system

postgres

public

pg_catalog

9 / 20

Some System Catalog tables are common to all databases in the cluster?

True

False

10 / 20

Tablespaces are used to define physical data layout?

False

True

11 / 20

What is the name of the catalog that stores metadata for all cluster objects?

Sysaux Catalog

Sys Catalog

Sysasm Catalog

System Catalog

12 / 20

What is a schema?

Namespace that store all objects of a database

A memory area used to cache data from LRU chains

The name used to refer to a super user account

This is the same as a user in Postgres

13 / 20

What is the purpose of the visibility map?

provides an audit trail for the database

shows a page to be vacuumed or frozen

shows referential relationships for tables

provides the data decryption key

14 / 20

The information_schema schema provides information on Postgres release notes?

False

True

15 / 20

What is the process first launched at server start?

postman

pginit

postgres

init

16 / 20

To understand each other, a client and a server must use one and the same interfacing protocol?

False

True

17 / 20

How does Postgres know which schema to use if not specified?

Directory Path

Schema Path

Access Path

Search Path

18 / 20

A Postgres cluster consists of 2 or more physical servers accessing one Postgres Instance?

True

False

19 / 20

Who is the Author of the Postgres 14 Internals book?

Dan Brown

Egor Rogov

Sam Altman

Paul Sammy

20 / 20

Postgres by default has built in connection pooling abilities?

True

False

Your score is

Created by

Paul Sammy

PostgreSQL 14 Internals Chapter 2

A quiz to test the knowledge of those reading and learning from Postgres 14 Internals book by Egor Rogov, covering topics in Chapter 2.

1 / 10

A phantom read anomaly occurs when?

The same transaction executes two identical queries returning a set of rows that satisfy a particular condition, while another transaction adds some other rows satisfying this condition and commits.

The same transaction executes two identical queries returning a set of rows that satisfy a particular condition, while another transaction also queries this same data.

The same transactions issues a commit, then a rollback to restore data to its original value

A transactions inserts a null value into a not null columns and commits

2 / 10

Data Consistency is best handled at the application layer rather than at the database layer?

True

False

3 / 10

Lost updates are forbidden by the standard at all isolation levels?

True

False

4 / 10

The SQL standard specifies three isolation levels?

True

False

5 / 10

What is the acronym used for the attributes that ensure Data consistency, integrity and durability?

SAFE

ACID

HIPPA

SOC2

6 / 10

Which of the below would best describe a dirty read?

a session being able to see uncommited data altered by another session

reading data direct from memory using pg_dirt

reading the data directly from file using a text editor such as vi or notepad

a session being able to see commited data altered by another session

7 / 10

Based on Snapshot Isolation use of MVCC which of the below are permitted?

choose 3

Repeatable Read

Read Committed

Read Uncommitted

Serializable

8 / 10

Which parameters sets the database default isolation level?

default_transaction_isolation

active_transaction_isolation

transaction_isolation_level

default_isolation_level

9 / 10

What is the default Isolation Level?

Read Committed

Repeatable Read

Read Uncommitted

Serializable

10 / 10

At any moment the database system can contain several versions of one and the same row?

False

True

Your score is

Created by

Paul Sammy

PostgreSQL 14 Internals Chapter 3

A quiz to test the knowledge of those reading and learning from Postgres 14 Internals book by Egor Rogov, covering topics in Chapter 3.

1 / 10

The page header is located in the highest address?

False

True

2 / 10

If a transaction aborts, all page changes are reverted(rolled back) in place?

False

True

3 / 10

index row headers like table row headers contain xmin and xmax fields?

False

True

4 / 10

What does an Item Pointer contain?

choose 3

tuple length

tuple status

tuple xid

tuple offset from the start of the page

5 / 10

status of a subtransaction is written into CLOG?

True

False

6 / 10

Which 2 items does a Virtual XID consist of?

sequential number

checksum

backend process ID

xmin

7 / 10

To identify different versions of one and the same row, PostgreSQL marks each of them with which two value?

xid

xmas

xmin

xmax

8 / 10

A page along with its tuples is read into the buffer cache with compression transformations to enhance cache efficiency?

True

False

9 / 10

UPDATE can be regarded as which 2 separate operations?

DELETE

MERGE

COMMIT

INSERT

10 / 10

Page free space can often become fragmented?

True

False

Your score is

Cookie	Duration	Description
cookielawinfo-checkbox-analytics	11 months	This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Analytics".
cookielawinfo-checkbox-functional	11 months	The cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional".
cookielawinfo-checkbox-necessary	11 months	This cookie is set by GDPR Cookie Consent plugin. The cookies is used to store the user consent for the cookies in the category "Necessary".
cookielawinfo-checkbox-others	11 months	This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Other.
cookielawinfo-checkbox-performance	11 months	This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Performance".
viewed_cookie_policy	11 months	The cookie is set by the GDPR Cookie Consent plugin and is used to store whether or not user has consented to the use of cookies. It does not store any personal data.