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 process first launched at server start?

postgres

init

pginit

postman

2 / 20

2. What is the purpose of wal writer?

writes WAL entries to disk

flushes dirty pages to disk.

collects usage statistics for the instance.

executes checkpoints

3 / 20

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

pg_tabspace

pg_tblspc

pg_tablespace

pg_symlinks

4 / 20

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

visiblilty map

table map

Main fork

free space map

5 / 20

5. pg_catalog schema is used to store system catalog tables?

False

True

6 / 20

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

False

True

7 / 20

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

used space map

wal space map

free space map

vacuum space map

8 / 20

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

9 / 20

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

choose 2

pg_global

pg_default

pg_temp

pg_tablespace

10 / 20

10. What is the purpose of the template0 database?

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

Useful for creating development schemas

11 / 20

11. Tablespaces are used to define physical data layout?

False

True

12 / 20

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

True

False

13 / 20

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

True

False

14 / 20

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

False

True

15 / 20

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

False

True

16 / 20

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

Search Path

Access Path

Directory Path

Schema Path

17 / 20

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

False

True

18 / 20

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

Sam Altman

Dan Brown

Egor Rogov

Paul Sammy

19 / 20

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

True

False

20 / 20

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

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. What is the default Isolation Level?

Read Committed

Read Uncommitted

Serializable

Repeatable Read

2 / 10

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

SAFE

ACID

HIPPA

SOC2

3 / 10

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

choose 3

Repeatable Read

Serializable

Read Uncommitted

Read Committed

4 / 10

4. 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 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 also queries this same data.

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

5 / 10

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

False

True

6 / 10

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

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

reading data direct from memory using pg_dirt

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

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

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

Read Uncommitted

Read Committed

Serializable

Repeatable Read

9 / 10

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

ALTER SYSTEM SET ISO=REPEATABLE_READ;

SET ISO=REPEATABLE_READ;

BEGIN ISOLATION LEVEL REPEATABLE READ;

CREATE EXTENSTION REPEATABLE_READ;

10 / 10

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

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

True

False

2 / 10

2. When a row is created, its xmin value is set to the transaction ID of which command?

INSERT

CREATE

COMMIT

DELETE

3 / 10

3. If a transaction is read only which kind of Transaction ID is it allocated?

heap XID

magic XID

temporary XID

virtual XID

4 / 10

4. Which function can we use to find the current transaction ID?

pg_current_id()

pg_current_xmin_id()

pg_current_xact_id()

pg_current_commit_id()

5 / 10

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

False

True

6 / 10

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

False

True

7 / 10

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

False

True

8 / 10

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

True

False

9 / 10

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

True

False

10 / 10

10. indexes do not use row versioning?

False

True

Your score is

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