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. What column in system catalogs servers as the Primary Key

oid

obj#

oid#

obj

2 / 20

2. Which fork is specific for unlogged tables?

Main fork

free space map

visiblilty map

Initialization fork

3 / 20

3. What is the name of the 2 default tablespaces created after initialization?

choose 2

pg_global

pg_default

pg_tablespace

pg_temp

4 / 20

4. Postgres uses a thread based process model?

False

True

5 / 20

5. What is the name of the mechanism used to store a row bigger than a page size?

BREAD

BAKE

GROW

TOAST

6 / 20

6. The pg_default tablespace should never be used to create user tables?

True

False

7 / 20

7. What is the purpose of the visibility map?

provides the data decryption key

shows referential relationships for tables

provides an audit trail for the database

shows a page to be vacuumed or frozen

8 / 20

8. System Catalog tables begin with which prefix?

sys_

pg_

cat_

dba_

9 / 20

9. What is the name of the directory that contains the files related to the Postgres cluster?

PGDATA

PGTIPS

PGBASE

PGCORE

10 / 20

10. What is the point of the pg_global tablespace?

stores system catalog objects that are common to the whole cluster

stores user tables that are common to the whole cluster

stores WAL logs used for global replication

stores temporary tables that are common to the whole cluster

11 / 20

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

True

False

12 / 20

12. Which of below are predefined schemas?

choose 3

pg_toast

pg_temp

information_schema

pg_schema

13 / 20

13. What is the purpose of autovacuum?

Performs a backup of WAL logs

Removes stale data from tables and indexes

Rebuilds indexes with b level greater than 2

Deletes old logs and traces on disk

14 / 20

14. It is the postmasters job to listener for incoming connections?

False

True

15 / 20

15. Who is the Author of the Postgres 14 Internals book?

Dan Brown

Egor Rogov

Sam Altman

Paul Sammy

16 / 20

16. The default Page size is 2k?

False

True

17 / 20

17. What is a schema?

The name used to refer to a super user account

A memory area used to cache data from LRU chains

This is the same as a user in Postgres

Namespace that store all objects of a database

18 / 20

18. What is the name of the system catalog table for relations?

pg_tables

pg_class

pg_system

pg_catalog

19 / 20

19. What command is used to create the Postgres cluster?

CreatePGC

Initialize

CreateCluster

StartNewPG

20 / 20

20. Users should not modify the template0 database

False

True

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

Serializable

Repeatable Read

Read Uncommitted

Read Committed

2 / 10

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

True

False

3 / 10

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

True

False

4 / 10

4. non-repeatable read anomaly occurs when?

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

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 twice, another transaction modifies this row between these reads issue a rollback.

5 / 10

5. What is the default Isolation Level?

Read Committed

Read Uncommitted

Repeatable Read

Serializable

6 / 10

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

True

False

7 / 10

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

choose 3

Serializable

Read Committed

Repeatable Read

Read Uncommitted

8 / 10

8. Snapshot isolation is preferred but increases the number of required locks?

False

True

9 / 10

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

ACID

SAFE

SOC2

HIPPA

10 / 10

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

ALTER SYSTEM SET ISO=REPEATABLE_READ;

CREATE EXTENSTION REPEATABLE_READ;

SET ISO=REPEATABLE_READ;

BEGIN ISOLATION LEVEL REPEATABLE READ;

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

transaction log

redo log

archive log

commit log

2 / 10

2. What does an Item Pointer contain?

choose 3

tuple xid

tuple offset from the start of the page

tuple status

tuple length

3 / 10

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

Each pointer uses 4 bytes

Each pointer uses 8 bytes

stored in PGDATA/itemptr directory

Also know as the pages table of contents

4 / 10

4. at any one time Postgres can have several versions of a row?

False

True

5 / 10

5. a transaction containing a savepoint is will still be considered as only a single transaction?

True

False

6 / 10

6. Tuples can also be referred to as columns?

True

False

7 / 10

7. Which 2 of the below represent transaction IDs used for row versioning?

xtime

xmax

xid

xmin

8 / 10

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

pg_current_id()

pg_current_commit_id()

pg_current_xmin_id()

pg_current_xact_id()

9 / 10

9. CLOG Pages are never cached in memory?

True

False

10 / 10

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

False

True

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.