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)

write-ahead log (WAL)

rollback segments (RBS)

2 / 20

2. pg_catalog schema is used to store system catalog tables?

True

False

3 / 20

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

Choose 2 option

Quorum

Aurora

Postgres Server

Instance

4 / 20

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

5GB

1MB

5MB

1GB

5 / 20

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

choose 3

triggers

sequences

tables

indexes

6 / 20

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

False

True

7 / 20

7. What is the purpose of the public schema?

schema used for heterogeneous replication

no such schema

restricted schema for postgres internal usage only

default schema for user objects

8 / 20

8. Which fork keeps track of available space within pages?

wal space map

used space map

vacuum space map

free space map

9 / 20

9. What is the purpose of the template0 database?

Useful for Postgres support Services to debug issues

Useful for creating development schemas

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

No such database

10 / 20

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

False

True

11 / 20

11. Which fork contains the actual table data?

free space map

table map

visiblilty map

Main fork

12 / 20

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

choose 2

pg_default

pg_global

pg_temp

pg_tablespace

13 / 20

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

pg_tables

pg_class

pg_catalog

pg_system

14 / 20

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

False

True

15 / 20

15. Users should not modify the template0 database

False

True

16 / 20

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

True

False

17 / 20

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

System Catalog

Sysasm Catalog

Sys Catalog

Sysaux Catalog

18 / 20

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

False

True

19 / 20

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

pg_symlinks

pg_tabspace

pg_tablespace

pg_tblspc

20 / 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

1. 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.

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

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

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.

2 / 10

2. Which of the below are valid Isolations Levels?

choose 2

Read Committed

Rollback Read

Serializable

Random Scatter

3 / 10

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

choose 3

Repeatable Read

Read Uncommitted

Read Committed

Serializable

4 / 10

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

False

True

5 / 10

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

True

False

6 / 10

6. What are some of database features we can use to avoid a non repeatable read?

Select more than 1 answer below:

Replace procedural code with declarative one.

Apply explicit locks

Use a single SQL operator

Issues a rollback after the commit to satisfy repeatable read.

7 / 10

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

ALTER SYSTEM SET ISO=REPEATABLE_READ;

SET ISO=REPEATABLE_READ;

CREATE EXTENSTION REPEATABLE_READ;

BEGIN ISOLATION LEVEL REPEATABLE READ;

8 / 10

8. The SQL standard specifies three isolation levels?

True

False

9 / 10

9. non-repeatable read anomaly occurs when?

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 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.

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

10 / 10

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

ACID

SAFE

HIPPA

SOC2

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. indexes do not use row versioning?

True

False

2 / 10

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

False

True

3 / 10

3. The page header stores checksum and the sizes of the other parts of the page?

False

True

4 / 10

4. Postgres table physical data files are always cross compatible across platforms?

True

False

5 / 10

5. status of a subtransaction is written into CLOG?

False

True

6 / 10

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

archive log

transaction log

commit log

redo log

7 / 10

7. Indexes values also support multi versioning with several versions of an index value existing at any point in time?

False

True

8 / 10

8. Rows of TOAST tables are handled in such a way that they are never update?

False

True

9 / 10

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

False

True

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.