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. A schema can belong to more than one database?

False

True

2 / 20

2. Postgres uses a thread based process model?

False

True

3 / 20

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

Paul Sammy

Egor Rogov

Sam Altman

Dan Brown

4 / 20

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

5 / 20

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

Initialize

CreatePGC

CreateCluster

StartNewPG

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 template1 database?

database used for temporary tables

regular database that you can use at your discretion

No such database

a template for all the other databases

8 / 20

8. Files are logically split into pages?

False

True

9 / 20

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

True

False

10 / 20

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

postgres

postman

pginit

init

11 / 20

11. Each Database has its own System Catalog?

True

False

12 / 20

12. TOAST tables reside in a seperate schema?

False

True

13 / 20

13. The default Page size is 2k?

False

True

14 / 20

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

choose 2

pg_global

pg_default

pg_temp

pg_tablespace

15 / 20

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

pg_system

pg_class

pg_catalog

pg_tables

16 / 20

16. What is the purpose of the public schema?

schema used for heterogeneous replication

restricted schema for postgres internal usage only

no such schema

default schema for user objects

17 / 20

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

vacuum space map

wal space map

used space map

free space map

18 / 20

18. Postgres by default has built in connection pooling abilities?

True

False

19 / 20

19. What is the point of the pg_global tablespace?

stores WAL logs used for global replication

stores user tables that are common to the whole cluster

stores temporary tables that are common to the whole cluster

stores system catalog objects that are common to the whole cluster

20 / 20

20. Which 3 databases exist directly after cluster initialization?

choose 3 options

template1

template0

postgres

sysaux

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

True

False

2 / 10

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

CREATE EXTENSTION REPEATABLE_READ;

BEGIN ISOLATION LEVEL REPEATABLE READ;

ALTER SYSTEM SET ISO=REPEATABLE_READ;

SET ISO=REPEATABLE_READ;

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

False

True

5 / 10

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

Select more than 1 answer below:

Use a single SQL operator

Replace procedural code with declarative one.

Apply explicit locks

Issues a rollback after the commit to satisfy repeatable read.

6 / 10

6. Which parameters sets the database default isolation level?

default_transaction_isolation

default_isolation_level

active_transaction_isolation

transaction_isolation_level

7 / 10

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

False

True

8 / 10

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

Serializable

Read Uncommitted

Repeatable Read

Read Committed

9 / 10

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

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

a session being able to see commited 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

10 / 10

10. The more locks a transaction acquires, the better it is isolated from other transactions?

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. indexes do not use row versioning?

True

False

2 / 10

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

False

True

3 / 10

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

False

True

4 / 10

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

stored in PGDATA/itemptr directory

Each pointer uses 4 bytes

Each pointer uses 8 bytes

Also know as the pages table of contents

5 / 10

5. The page header is located in the highest address?

False

True

6 / 10

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

False

True

7 / 10

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

False

True

8 / 10

8. Tuples can also be referred to as columns?

True

False

9 / 10

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

False

True

10 / 10

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

xmin

xmas

xid

xmax

Your score is

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