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. Files are logically split into pages?

True

False

2 / 20

2. What is the name of the catalog that stores metadata for all cluster objects?

Sysasm Catalog

Sys Catalog

System Catalog

Sysaux Catalog

3 / 20

3. What is a schema?

A memory area used to cache data from LRU chains

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

4 / 20

4. What is the process first launched at server start?

init

pginit

postman

postgres

5 / 20

5. When PostgreSQL is running what can it be referred to as?

Choose 2 option

Postgres Server

Instance

Quorum

Aurora

6 / 20

6. Which fork contains the actual table data?

table map

Main fork

free space map

visiblilty map

7 / 20

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

oid

oid#

obj#

obj

8 / 20

8. What is the purpose of autovacuum?

Performs a backup of WAL logs

Deletes old logs and traces on disk

Removes stale data from tables and indexes

Rebuilds indexes with b level greater than 2

9 / 20

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

choose 2

pg_global

pg_tablespace

pg_default

pg_temp

10 / 20

10. Which fork is specific for unlogged tables?

Main fork

visiblilty map

Initialization fork

free space map

11 / 20

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

False

True

12 / 20

12. What is the purpose of the template0 database?

Useful for Postgres support Services to debug issues

No such database

Useful for creating development schemas

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

13 / 20

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

online redo logs (ORL)

write-ahead log (WAL)

rollback segments (RBS)

undo segments (UNDO)

14 / 20

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

False

True

15 / 20

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

False

True

16 / 20

16. System Catalog tables begin with which prefix?

cat_

sys_

pg_

dba_

17 / 20

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

PGBASE

PGTIPS

PGCORE

PGDATA

18 / 20

18. Which of below are predefined schemas?

choose 2

public

pg_catalog

system

postgres

19 / 20

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

pg_class

pg_catalog

pg_tables

pg_system

20 / 20

20. Each Database has its own System Catalog?

False

True

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 statements will start a transaction as Read Repeatable?

CREATE EXTENSTION REPEATABLE_READ;

ALTER SYSTEM SET ISO=REPEATABLE_READ;

SET ISO=REPEATABLE_READ;

BEGIN ISOLATION LEVEL REPEATABLE READ;

3 / 10

3. 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.

4 / 10

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

True

False

5 / 10

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

Select more than 1 answer below:

Issues a rollback after the commit to satisfy repeatable read.

Apply explicit locks

Use a single SQL operator

Replace procedural code with declarative one.

6 / 10

6. Which parameters sets the database default isolation level?

active_transaction_isolation

transaction_isolation_level

default_isolation_level

default_transaction_isolation

7 / 10

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

choose 3

Read Committed

Read Uncommitted

Serializable

Repeatable Read

8 / 10

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

True

False

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

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

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. If a transaction aborts, all page changes are reverted(rolled back) in place?

False

True

2 / 10

2. status of a subtransaction is written into CLOG?

False

True

3 / 10

3. To identify different versions of one and the same row, PostgreSQL marks each of them with which two value?

xmin

xmax

xid

xmas

4 / 10

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

redo log

commit log

transaction log

archive log

5 / 10

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

CREATE

INSERT

DELETE

COMMIT

6 / 10

6. Tuples can also be referred to as columns?

True

False

7 / 10

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

pagedetect

pageinspect

pageheadinfo

pagesize

8 / 10

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

False

True

9 / 10

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

False

True

10 / 10

10. CLOG Pages are never cached in memory?

False

True

Your score is

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