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

obj

obj#

oid#

oid

2 / 20

2. Postgres uses a thread based process model?

False

True

3 / 20

3. Files are logically split into pages?

False

True

4 / 20

4. Which fork is specific for unlogged tables?

free space map

Main fork

Initialization fork

visiblilty map

5 / 20

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

Sam Altman

Dan Brown

Paul Sammy

Egor Rogov

6 / 20

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

True

False

7 / 20

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

False

True

8 / 20

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

True

False

9 / 20

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

Initialize

CreatePGC

StartNewPG

CreateCluster

10 / 20

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

wal space map

used space map

vacuum space map

free space map

11 / 20

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

12 / 20

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

False

True

13 / 20

13. What is the purpose of the postgres database?

a template for all the other database

regular database that you can use at your discretion

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

No such database

14 / 20

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

PGCORE

PGBASE

PGDATA

PGTIPS

15 / 20

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

choose 2

pg_global

pg_tablespace

pg_default

pg_temp

16 / 20

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

free space map

table map

Main fork

visiblilty map

17 / 20

17. What is a schema?

Namespace that store all objects of a database

A memory area used to cache data from LRU chains

This is the same as a user in Postgres

The name used to refer to a super user account

18 / 20

18. Tablespaces are used to define physical data layout?

True

False

19 / 20

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

pg_system

pg_tables

pg_class

pg_catalog

20 / 20

20. Each Database has its own System Catalog?

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. The SQL standard specifies three isolation levels?

False

True

2 / 10

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

choose 3

Repeatable Read

Read Uncommitted

Read Committed

Serializable

3 / 10

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

HIPPA

ACID

SOC2

SAFE

4 / 10

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

True

False

5 / 10

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

True

False

6 / 10

6. 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 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.

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

7 / 10

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

True

False

8 / 10

8. 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 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

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.

9 / 10

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

True

False

10 / 10

10. 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

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

False

True

2 / 10

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

clog

heap

dump

view

3 / 10

3. CLOG files are stored in which directory?

PGDATA/pg_commit

PGDATA/clog

PGDATA/pg_clog

PGDATA/pg_xact

4 / 10

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

commit log

transaction log

archive log

redo log

5 / 10

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

False

True

6 / 10

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

False

True

7 / 10

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

False

True

8 / 10

8. virtual IDs exist only in PGDATA/pg_vxid when not cached?

False

True

9 / 10

9. Tuples can also be referred to as columns?

True

False

10 / 10

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

xtime

xid

xmax

xmin

Your score is

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