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

Which fork keeps track of available space within pages?

used space map

wal space map

vacuum space map

free space map

2 / 20

A single Postgres Instance can server only one database?

True

False

3 / 20

TOAST tables reside in a seperate schema?

False

True

4 / 20

What is a schema?

Namespace that store all objects of a database

The name used to refer to a super user account

This is the same as a user in Postgres

A memory area used to cache data from LRU chains

5 / 20

pg_catalog schema is used to store system catalog tables?

False

True

6 / 20

A schema can belong to more than one database?

True

False

7 / 20

Postgres server spawns a new backend session for each connection?

False

True

8 / 20

Which fork is specific for unlogged tables?

visiblilty map

free space map

Main fork

Initialization fork

9 / 20

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

False

True

10 / 20

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

Main fork

visiblilty map

table map

free space map

11 / 20

What command is used to create the Postgres cluster?

StartNewPG

CreatePGC

Initialize

CreateCluster

12 / 20

System Catalog tables begin with which prefix?

sys_

dba_

cat_

pg_

13 / 20

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

pg_symlinks

pg_tblspc

pg_tabspace

pg_tablespace

14 / 20

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

15 / 20

What is the default standard size for a fork file?

1MB

1GB

5GB

5MB

16 / 20

What is the purpose of the public schema?

restricted schema for postgres internal usage only

schema used for heterogeneous replication

no such schema

default schema for user objects

17 / 20

What is the purpose of the postgres database?

No such database

regular database that you can use at your discretion

a template for all the other database

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

18 / 20

Each Database has its own System Catalog?

False

True

19 / 20

What is the process first launched at server start?

postgres

pginit

init

postman

20 / 20

The information_schema schema provides information on Postgres release notes?

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

A phantom read anomaly occurs when?

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.

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

2 / 10

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 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 and modifies this row and commits the change.

3 / 10

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

choose 3

Repeatable Read

Read Uncommitted

Serializable

Read Committed

4 / 10

Which parameters sets the database default isolation level?

transaction_isolation_level

default_transaction_isolation

default_isolation_level

active_transaction_isolation

5 / 10

The SQL standard specifies three isolation levels?

True

False

6 / 10

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

False

True

7 / 10

What are some of database features we can use to avoid a non repeatable read?

Select more than 1 answer below:

Replace procedural code with declarative one.

Issues a rollback after the commit to satisfy repeatable read.

Apply explicit locks

Use a single SQL operator

8 / 10

Which of the below are valid Isolations Levels?

choose 2

Read Committed

Random Scatter

Serializable

Rollback Read

9 / 10

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

Repeatable Read

Read Uncommitted

Serializable

Read Committed

10 / 10

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

SAFE

HIPPA

ACID

SOC2

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

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

True

False

2 / 10

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

pagedetect

pageheadinfo

pagesize

pageinspect

3 / 10

Each page has a layer that usually consists of?

choose 2

page header

flashback block

undo segment

free space

4 / 10

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

True

False

5 / 10

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

redo log

commit log

archive log

transaction log

6 / 10

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

xid

xmax

xtime

xmin

7 / 10

indexes do not use row versioning?

False

True

8 / 10

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

False

True

9 / 10

UPDATE can be regarded as which 2 separate operations?

COMMIT

MERGE

DELETE

INSERT

10 / 10

Page free space can often become fragmented?

True

False

Your score is

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