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

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

False

True

2 / 20

What is the purpose of wal writer?

executes checkpoints

writes WAL entries to disk

collects usage statistics for the instance.

flushes dirty pages to disk.

3 / 20

What is a schema?

The name used to refer to a super user account

Namespace that store all objects of a database

This is the same as a user in Postgres

A memory area used to cache data from LRU chains

4 / 20

Which fork keeps track of available space within pages?

free space map

wal space map

used space map

vacuum space map

5 / 20

TOAST tables reside in a seperate schema?

True

False

6 / 20

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

Search Path

Schema Path

Directory Path

Access Path

7 / 20

Each tablespaces can only be assigned for use by one database

True

False

8 / 20

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

True

False

9 / 20

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

pg_tblspc

pg_symlinks

pg_tablespace

pg_tabspace

10 / 20

How many files or forks on disk will a 10Mb table with no index have?

11 / 20

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

True

False

12 / 20

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

TOAST

BREAD

BAKE

GROW

13 / 20

Files are logically split into pages?

False

True

14 / 20

What is the default standard size for a fork file?

1MB

5MB

5GB

1GB

15 / 20

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

choose 3

sequences

indexes

tables

triggers

16 / 20

What is the process first launched at server start?

pginit

postgres

postman

init

17 / 20

What is the purpose of the public schema?

restricted schema for postgres internal usage only

no such schema

default schema for user objects

schema used for heterogeneous replication

18 / 20

What is the purpose of autovacuum?

Deletes old logs and traces on disk

Removes stale data from tables and indexes

Performs a backup of WAL logs

Rebuilds indexes with b level greater than 2

19 / 20

Which fork contains the actual table data?

Main fork

free space map

visiblilty map

table map

20 / 20

Who is the Author of the Postgres 14 Internals book?

Dan Brown

Egor Rogov

Paul Sammy

Sam Altman

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

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

choose 3

Repeatable Read

Read Uncommitted

Serializable

Read Committed

2 / 10

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 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.

3 / 10

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

ACID

SOC2

HIPPA

SAFE

4 / 10

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

CREATE EXTENSTION REPEATABLE_READ;

BEGIN ISOLATION LEVEL REPEATABLE READ;

SET ISO=REPEATABLE_READ;

ALTER SYSTEM SET ISO=REPEATABLE_READ;

5 / 10

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

False

True

6 / 10

The SQL standard specifies three isolation levels?

True

False

7 / 10

What is the default Isolation Level?

Repeatable Read

Read Uncommitted

Read Committed

Serializable

8 / 10

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

9 / 10

Which of the below are valid Isolations Levels?

choose 2

Rollback Read

Random Scatter

Serializable

Read Committed

10 / 10

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

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

Page free space can often become fragmented?

False

True

2 / 10

status of a subtransaction is written into CLOG?

True

False

3 / 10

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

xtime

xid

xmin

xmax

4 / 10

UPDATE can be regarded as which 2 separate operations?

INSERT

COMMIT

MERGE

DELETE

5 / 10

CLOG Pages are never cached in memory?

False

True

6 / 10

What does an Item Pointer contain?

choose 3

tuple xid

tuple status

tuple offset from the start of the page

tuple length

7 / 10

Each page has a layer that usually consists of?

choose 2

undo segment

free space

page header

flashback block

8 / 10

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

True

False

9 / 10

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

False

True

10 / 10

Which 2 items does a Virtual XID consist of?

checksum

xmin

sequential number

backend process ID

Your score is

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