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. Postgres by default has built in connection pooling abilities?

True

False

2 / 20

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

rollback segments (RBS)

undo segments (UNDO)

write-ahead log (WAL)

online redo logs (ORL)

3 / 20

3. What is the purpose of the postgres database?

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

No such database

regular database that you can use at your discretion

a template for all the other database

4 / 20

4. What is another name for the postgres process?

postmanager

masterprocess

postmaster

aurora

5 / 20

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

choose 3

sequences

indexes

tables

triggers

6 / 20

6. The default Page size is 2k?

False

True

7 / 20

7. What is the purpose of the visibility map?

provides an audit trail for the database

provides the data decryption key

shows referential relationships for tables

shows a page to be vacuumed or frozen

8 / 20

8. Users should not modify the template0 database

False

True

9 / 20

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

Egor Rogov

Dan Brown

Sam Altman

Paul Sammy

10 / 20

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

choose 2

pg_tablespace

pg_temp

pg_default

pg_global

11 / 20

11. Files are logically split into pages?

True

False

12 / 20

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

pg_system

pg_tables

pg_catalog

pg_class

13 / 20

13. What is the purpose of autovacuum?

Rebuilds indexes with b level greater than 2

Deletes old logs and traces on disk

Removes stale data from tables and indexes

Performs a backup of WAL logs

14 / 20

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

False

True

15 / 20

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

PGDATA

PGTIPS

PGCORE

PGBASE

16 / 20

16. Which 3 databases exist directly after cluster initialization?

choose 3 options

template0

template1

sysaux

postgres

17 / 20

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

True

False

18 / 20

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

Initialize

CreateCluster

StartNewPG

CreatePGC

19 / 20

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

20 / 20

20. Each Database has its own System Catalog?

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

False

True

2 / 10

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

False

True

3 / 10

3. 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;

4 / 10

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

False

True

5 / 10

5. 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.

6 / 10

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

False

True

7 / 10

7. 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 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.

A transaction reads one and the same row once and modifies this row and commits the change.

8 / 10

8. What is the default Isolation Level?

Serializable

Repeatable Read

Read Committed

Read Uncommitted

9 / 10

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

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

a session being able to see uncommited 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 SQL standard specifies three isolation levels?

False

True

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. Which 2 items does a Virtual XID consist of?

sequential number

xmin

backend process ID

checksum

2 / 10

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

True

False

3 / 10

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

Each pointer uses 8 bytes

Also know as the pages table of contents

stored in PGDATA/itemptr directory

Each pointer uses 4 bytes

4 / 10

4. Page header sizes can be easily displayed using the <choose from answers> extension

pagesize

pageheadinfo

pagedetect

pageinspect

5 / 10

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

False

True

6 / 10

6. Tuples can also be referred to as columns?

True

False

7 / 10

7. What does an Item Pointer contain?

choose 3

tuple offset from the start of the page

tuple status

tuple length

tuple xid

8 / 10

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

False

True

9 / 10

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

False

True

10 / 10

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

archive log

commit log

redo log

transaction log

Your score is

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