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

1. To be able to restore data consistency, Postgres maintains

undo segments (UNDO)

online redo logs (ORL)

rollback segments (RBS)

write-ahead log (WAL)

2 / 20

2. Tablespaces can be used to segregate data based on performance needs?

False

True

3 / 20

3. What is the purpose of the template1 database?

a template for all the other databases

database used for temporary tables

No such database

regular database that you can use at your discretion

4 / 20

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

Search Path

Schema Path

Access Path

Directory Path

5 / 20

5. Files are logically split into pages?

True

False

6 / 20

6. Each tablespaces can only be assigned for use by one database

True

False

7 / 20

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

True

False

8 / 20

8. If we create a new tablespace which directory will symbolic links be created from?

pg_tabspace

pg_symlinks

pg_tablespace

pg_tblspc

9 / 20

9. The information_schema schema provides information on Postgres release notes?

False

True

10 / 20

10. When PostgreSQL is running what can it be referred to as?

Choose 2 option

Instance

Quorum

Postgres Server

Aurora

11 / 20

11. What 3 files/forks as a minimum make up a table on disk?

table map

visiblilty map

free space map

Main fork

12 / 20

12. What is the point of the pg_global tablespace?

stores WAL logs used for global replication

stores temporary tables that are common to the whole cluster

stores user tables that are common to the whole cluster

stores system catalog objects that are common to the whole cluster

13 / 20

13. What is the process first launched at server start?

postman

pginit

init

postgres

14 / 20

14. How many rows in a page does Postgres aim to have before considering TOAST?

15 / 20

15. The default Page size is 2k?

False

True

16 / 20

16. Postgres server spawns a new backend session for each connection?

False

True

17 / 20

17. A schema can belong to more than one database?

True

False

18 / 20

18. What is the default standard size for a fork file?

5MB

1MB

1GB

5GB

19 / 20

19. What is the purpose of the public schema?

default schema for user objects

no such schema

schema used for heterogeneous replication

restricted schema for postgres internal usage only

20 / 20

20. Which 3 databases exist directly after cluster initialization?

choose 3 options

template1

postgres

sysaux

template0

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

1. Which of the below would best describe a dirty read?

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

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

reading data direct from memory using pg_dirt

2 / 10

2. Which parameters sets the database default isolation level?

default_transaction_isolation

transaction_isolation_level

active_transaction_isolation

default_isolation_level

3 / 10

3. Which isolation level in theory could mean an application does not have to consider isolation anomalies?

Serializable

Read Uncommitted

Repeatable Read

Read Committed

4 / 10

4. non-repeatable read anomaly occurs when?

A transaction reads one and the same row twice, another transaction modifies this row between these reads issue a rollback.

A transaction reads one and the same row twice, another transaction modifies this row between these reads and commits the change.

A transaction reads one and the same row once and modifies this row and commits the change.

A transaction reads one and the same row once, another transaction modifies this row between these reads and commits the change.

5 / 10

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

SAFE

SOC2

HIPPA

ACID

6 / 10

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

True

False

7 / 10

7. The SQL standard specifies three isolation levels?

True

False

8 / 10

8. which of the below statements will start a transaction as Read Repeatable?

SET ISO=REPEATABLE_READ;

CREATE EXTENSTION REPEATABLE_READ;

ALTER SYSTEM SET ISO=REPEATABLE_READ;

BEGIN ISOLATION LEVEL REPEATABLE READ;

9 / 10

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

True

False

10 / 10

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

True

False

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

1. Tuples can also be referred to as columns?

False

True

2 / 10

2. virtual IDs exist only in PGDATA/pg_vxid when not cached?

True

False

3 / 10

3. UPDATE can be regarded as which 2 separate operations?

DELETE

MERGE

COMMIT

INSERT

4 / 10

4. When a transaction is committed Postgres uses a special <replace with answer> structure?

archive log

commit log

redo log

transaction log

5 / 10

5. CLOG contains how many bits for each transaction?

6 / 10

6. psql provides a special mode that allows you to continue a transaction after a failure?

True

False

7 / 10

7. Page header sizes can be easily displayed using the <choose from answers> extension

pageinspect

pagedetect

pagesize

pageheadinfo

8 / 10

8. Which function can we use to find the current transaction ID?

pg_current_xact_id()

pg_current_commit_id()

pg_current_xmin_id()

pg_current_id()

9 / 10

9. Which of the below are true about a Pages Item Pointer?

Each pointer uses 4 bytes

stored in PGDATA/itemptr directory

Each pointer uses 8 bytes

Also know as the pages table of contents

10 / 10

10. The page Special Space is located at the start of the page with highest address

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.