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. Users should not modify the template0 database

True

False

2 / 20

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

False

True

3 / 20

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

pg_tabspace

pg_symlinks

pg_tablespace

pg_tblspc

4 / 20

4. Which fork is specific for unlogged tables?

free space map

visiblilty map

Main fork

Initialization fork

5 / 20

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

False

True

6 / 20

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

7 / 20

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

5MB

5GB

1GB

1MB

8 / 20

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

choose 3

tables

sequences

triggers

indexes

9 / 20

9. What is the purpose of the template1 database?

a template for all the other databases

database used for temporary tables

regular database that you can use at your discretion

No such database

10 / 20

10. A single Postgres Instance can server only one database?

True

False

11 / 20

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

True

False

12 / 20

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

True

False

13 / 20

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

choose 2

pg_tablespace

pg_default

pg_global

pg_temp

14 / 20

14. What is the purpose of the template0 database?

Useful for creating development schemas

Useful for Postgres support Services to debug issues

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

No such database

15 / 20

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

Search Path

Access Path

Schema Path

Directory Path

16 / 20

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

undo segments (UNDO)

rollback segments (RBS)

write-ahead log (WAL)

online redo logs (ORL)

17 / 20

17. What is the purpose of the public schema?

schema used for heterogeneous replication

restricted schema for postgres internal usage only

default schema for user objects

no such schema

18 / 20

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

Dan Brown

Egor Rogov

Paul Sammy

Sam Altman

19 / 20

19. Which of below are predefined schemas?

choose 3

information_schema

pg_toast

pg_temp

pg_schema

20 / 20

20. TOAST tables reside in a seperate schema?

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

choose 3

Serializable

Read Uncommitted

Read Committed

Repeatable Read

2 / 10

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

3 / 10

3. 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.

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

4 / 10

4. The SQL standard specifies three isolation levels?

False

True

5 / 10

5. What is the default Isolation Level?

Repeatable Read

Read Committed

Read Uncommitted

Serializable

6 / 10

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

HIPPA

SAFE

ACID

SOC2

7 / 10

7. 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.

Use a single SQL operator

Issues a rollback after the commit to satisfy repeatable read.

Apply explicit locks

8 / 10

8. 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;

9 / 10

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

False

True

10 / 10

10. Which of the below are valid Isolations Levels?

choose 2

Random Scatter

Rollback Read

Serializable

Read Committed

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. CLOG files are stored in which directory?

PGDATA/pg_commit

PGDATA/pg_xact

PGDATA/pg_clog

PGDATA/clog

2 / 10

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

False

True

3 / 10

3. indexes do not use row versioning?

True

False

4 / 10

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

False

True

5 / 10

5. Information about subtransactions is stored under?

PGDATA/pg_min

PGDATA/pg_xid

PGDATA/subtrans

PGDATA/pg_subtrans

6 / 10

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

Each pointer uses 8 bytes

Each pointer uses 4 bytes

Also know as the pages table of contents

stored in PGDATA/itemptr directory

7 / 10

7. Which 2 items does a Virtual XID consist of?

xmin

backend process ID

sequential number

checksum

8 / 10

8. Each page has a layer that usually consists of?

choose 2

flashback block

undo segment

free space

page header

9 / 10

9. In Postgres, tables are often referred to as which of the below?

dump

heap

view

clog

10 / 10

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

True

False

Your score is

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