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

pginit

init

postman

2 / 20

2. TOAST tables reside in a seperate schema?

False

True

3 / 20

3. What is the purpose of the postgres database?

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

No such database

a template for all the other database

regular database that you can use at your discretion

4 / 20

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

used space map

wal space map

vacuum space map

free space map

5 / 20

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

visiblilty map

free space map

table map

Main fork

6 / 20

6. What is the purpose of the template1 database?

regular database that you can use at your discretion

a template for all the other databases

No such database

database used for temporary tables

7 / 20

7. Postgres uses a thread based process model?

False

True

8 / 20

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

9 / 20

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

False

True

10 / 20

10. The pg_default tablespace should never be used to create user tables?

True

False

11 / 20

11. What is a schema?

A memory area used to cache data from LRU chains

This is the same as a user in Postgres

Namespace that store all objects of a database

The name used to refer to a super user account

12 / 20

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

False

True

13 / 20

13. Which of below are predefined schemas?

choose 2

pg_catalog

postgres

public

system

14 / 20

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

True

False

15 / 20

15. What is the point of the pg_global tablespace?

stores user tables that are common to the whole cluster

stores system catalog objects that are common to the whole cluster

stores WAL logs used for global replication

stores temporary tables that are common to the whole cluster

16 / 20

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

5GB

1GB

5MB

1MB

17 / 20

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

False

True

18 / 20

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

False

True

19 / 20

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

Sysasm Catalog

System Catalog

Sysaux Catalog

Sys Catalog

20 / 20

20. 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

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

False

True

2 / 10

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

Select more than 1 answer below:

Apply explicit locks

Replace procedural code with declarative one.

Issues a rollback after the commit to satisfy repeatable read.

Use a single SQL operator

3 / 10

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

SET ISO=REPEATABLE_READ;

BEGIN ISOLATION LEVEL REPEATABLE READ;

ALTER SYSTEM SET ISO=REPEATABLE_READ;

CREATE EXTENSTION REPEATABLE_READ;

4 / 10

4. 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

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

reading data direct from memory using pg_dirt

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

5 / 10

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

True

False

6 / 10

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

True

False

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 of the below are valid Isolations Levels?

choose 2

Read Committed

Rollback Read

Random Scatter

Serializable

9 / 10

9. Which parameters sets the database default isolation level?

transaction_isolation_level

default_isolation_level

active_transaction_isolation

default_transaction_isolation

10 / 10

10. The SQL standard specifies three isolation levels?

True

False

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

True

False

2 / 10

2. Which of the below are true about a Pages Item Pointer?

Each pointer uses 4 bytes

stored in PGDATA/itemptr directory

Each pointer uses 8 bytes

Also know as the pages table of contents

3 / 10

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

True

False

4 / 10

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

False

True

5 / 10

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

xtime

xmax

xmin

xid

6 / 10

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

True

False

7 / 10

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

xmas

xmax

xid

xmin

8 / 10

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

choose 2

flashback block

free space

page header

undo segment

9 / 10

9. The page header stores checksum and the sizes of the other parts of the page?

True

False

10 / 10

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

True

False

Your score is

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