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 purpose of autovacuum?

Removes stale data from tables and indexes

Deletes old logs and traces on disk

Performs a backup of WAL logs

Rebuilds indexes with b level greater than 2

2 / 20

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

False

True

3 / 20

3. Users should not modify the template0 database

True

False

4 / 20

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

Choose 2 option

Aurora

Postgres Server

Instance

Quorum

5 / 20

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

1MB

1GB

5GB

5MB

6 / 20

6. What is the purpose of the template1 database?

No such database

regular database that you can use at your discretion

a template for all the other databases

database used for temporary tables

7 / 20

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

Sysasm Catalog

Sys Catalog

System Catalog

Sysaux Catalog

8 / 20

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

True

False

9 / 20

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

True

False

10 / 20

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

11 / 20

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

12 / 20

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

False

True

13 / 20

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

True

False

14 / 20

14. What is a schema?

This is the same as a user in Postgres

Namespace that store all objects of a database

A memory area used to cache data from LRU chains

The name used to refer to a super user account

15 / 20

15. What is the point of the pg_global tablespace?

stores WAL logs used for global replication

stores system catalog objects that are common to the whole cluster

stores user tables that are common to the whole cluster

stores temporary tables that are common to the whole cluster

16 / 20

16. Which 3 databases exist directly after cluster initialization?

choose 3 options

template0

sysaux

template1

postgres

17 / 20

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

pg_catalog

pg_system

pg_class

pg_tables

18 / 20

18. What is the purpose of the template0 database?

Useful for Postgres support Services to debug issues

Useful for creating development schemas

No such database

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

19 / 20

19. pg_catalog schema is used to store system catalog tables?

True

False

20 / 20

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

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. 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;

2 / 10

2. 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 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.

3 / 10

3. Which of the below are valid Isolations Levels?

choose 2

Rollback Read

Random Scatter

Read Committed

Serializable

4 / 10

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

Repeatable Read

Read Committed

Serializable

Read Uncommitted

5 / 10

5. What is the default Isolation Level?

Read Committed

Repeatable Read

Serializable

Read Uncommitted

6 / 10

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

True

False

7 / 10

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

ACID

SAFE

SOC2

HIPPA

8 / 10

8. 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.

Apply explicit locks

Use a single SQL operator

Issues a rollback after the commit to satisfy repeatable read.

9 / 10

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

True

False

10 / 10

10. Which parameters sets the database default isolation level?

transaction_isolation_level

default_transaction_isolation

default_isolation_level

active_transaction_isolation

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. Rows of TOAST tables are handled in such a way that they are never update?

False

True

2 / 10

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

False

True

3 / 10

3. indexes do not use row versioning?

True

False

4 / 10

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

xtime

xmax

xmin

xid

5 / 10

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

False

True

6 / 10

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

False

True

7 / 10

7. Page free space can often become fragmented?

False

True

8 / 10

8. Tuples can also be referred to as columns?

False

True

9 / 10

9. status of a subtransaction is written into CLOG?

False

True

10 / 10

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

redo log

archive log

commit log

transaction log

Your score is

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