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. TOAST tables reside in a seperate schema?

False

True

2 / 20

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

5GB

1MB

5MB

1GB

3 / 20

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

True

False

4 / 20

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

PGBASE

PGDATA

PGCORE

PGTIPS

5 / 20

5. What is the point of the pg_global tablespace?

stores temporary tables that are common to the whole cluster

stores system catalog objects that are common to the whole cluster

stores user tables that are common to the whole cluster

stores WAL logs used for global replication

6 / 20

6. System Catalog tables begin with which prefix?

cat_

dba_

pg_

sys_

7 / 20

7. The information_schema schema provides information on Postgres release notes?

True

False

8 / 20

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

choose 2

pg_tablespace

pg_default

pg_global

pg_temp

9 / 20

9. Which fork is specific for unlogged tables?

Initialization fork

free space map

visiblilty map

Main fork

10 / 20

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

vacuum space map

wal space map

free space map

used space map

11 / 20

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

False

True

12 / 20

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

Access Path

Schema Path

Search Path

Directory Path

13 / 20

13. What is the name of the mechanism used to store a row bigger than a page size?

BAKE

GROW

BREAD

TOAST

14 / 20

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

choose 3

triggers

tables

indexes

sequences

15 / 20

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

rollback segments (RBS)

undo segments (UNDO)

online redo logs (ORL)

write-ahead log (WAL)

16 / 20

16. What column in system catalogs servers as the Primary Key

obj#

oid

obj

oid#

17 / 20

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

False

True

18 / 20

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

True

False

19 / 20

19. What is the purpose of the template0 database?

No such database

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

Useful for Postgres support Services to debug issues

Useful for creating development schemas

20 / 20

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

Sam Altman

Dan Brown

Paul Sammy

Egor Rogov

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 acronym used for the attributes that ensure Data consistency, integrity and durability?

HIPPA

ACID

SOC2

SAFE

2 / 10

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

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

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

3 / 10

3. A phantom read anomaly occurs when?

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

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 also queries this same data.

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.

4 / 10

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

ALTER SYSTEM SET ISO=REPEATABLE_READ;

BEGIN ISOLATION LEVEL REPEATABLE READ;

CREATE EXTENSTION REPEATABLE_READ;

SET ISO=REPEATABLE_READ;

5 / 10

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

False

True

6 / 10

6. What is the default Isolation Level?

Repeatable Read

Read Committed

Read Uncommitted

Serializable

7 / 10

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

True

False

8 / 10

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

Repeatable Read

Serializable

Read Uncommitted

Read Committed

9 / 10

9. 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 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.

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

10 / 10

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

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. Information about subtransactions is stored under?

PGDATA/subtrans

PGDATA/pg_subtrans

PGDATA/pg_xid

PGDATA/pg_min

2 / 10

2. Each page has a layer that usually consists of?

choose 2

free space

flashback block

undo segment

page header

3 / 10

3. What does an Item Pointer contain?

choose 3

tuple length

tuple xid

tuple status

tuple offset from the start of the page

4 / 10

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

True

False

5 / 10

5. Which 2 items does a Virtual XID consist of?

backend process ID

checksum

xmin

sequential number

6 / 10

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

pg_current_xact_id()

pg_current_xmin_id()

pg_current_id()

pg_current_commit_id()

7 / 10

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

dump

heap

clog

view

8 / 10

8. status of a subtransaction is written into CLOG?

True

False

9 / 10

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

xid

xmin

xtime

xmax

10 / 10

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

True

False

Your score is

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