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 is the purpose of the template1 database?

No such database

a template for all the other databases

database used for temporary tables

regular database that you can use at your discretion

2 / 20

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

Dan Brown

Paul Sammy

Egor Rogov

Sam Altman

3 / 20

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

False

True

4 / 20

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

CreateCluster

Initialize

CreatePGC

StartNewPG

5 / 20

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

pg_tblspc

pg_tablespace

pg_tabspace

pg_symlinks

6 / 20

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

False

True

7 / 20

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

False

True

8 / 20

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

True

False

9 / 20

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

free space map

used space map

wal space map

vacuum space map

10 / 20

10. System Catalog tables begin with which prefix?

sys_

dba_

pg_

cat_

11 / 20

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

PGCORE

PGDATA

PGTIPS

PGBASE

12 / 20

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

table map

visiblilty map

Main fork

free space map

13 / 20

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

True

False

14 / 20

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

init

pginit

postgres

postman

15 / 20

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

16 / 20

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

True

False

17 / 20

17. Postgres uses a thread based process model?

True

False

18 / 20

18. What is the purpose of the public schema?

schema used for heterogeneous replication

default schema for user objects

no such schema

restricted schema for postgres internal usage only

19 / 20

19. Users should not modify the template0 database

False

True

20 / 20

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

5GB

1MB

1GB

5MB

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. What is the default Isolation Level?

Serializable

Read Uncommitted

Repeatable Read

Read Committed

2 / 10

2. A phantom read anomaly occurs when?

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

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.

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

3 / 10

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

reading data direct from memory using pg_dirt

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 the data directly from file using a text editor such as vi or notepad

4 / 10

4. The SQL standard specifies three isolation levels?

False

True

5 / 10

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

choose 3

Repeatable Read

Read Committed

Read Uncommitted

Serializable

6 / 10

6. Which of the below are valid Isolations Levels?

choose 2

Read Committed

Random Scatter

Rollback Read

Serializable

7 / 10

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

False

True

8 / 10

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

True

False

9 / 10

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

True

False

10 / 10

10. 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.

Issues a rollback after the commit to satisfy repeatable read.

Use a single SQL operator

Apply explicit locks

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

True

False

2 / 10

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

False

True

3 / 10

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

False

True

4 / 10

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

True

False

5 / 10

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

Each pointer uses 8 bytes

Also know as the pages table of contents

Each pointer uses 4 bytes

stored in PGDATA/itemptr directory

6 / 10

6. CLOG Pages are never cached in memory?

False

True

7 / 10

7. What does an Item Pointer contain?

choose 3

tuple status

tuple xid

tuple length

tuple offset from the start of the page

8 / 10

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

False

True

9 / 10

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

False

True

10 / 10

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

False

True

Your score is

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