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. System Catalog tables begin with which prefix?

cat_

dba_

pg_

sys_

2 / 20

2. What is the point of the pg_global tablespace?

stores temporary tables that are common to the whole cluster

stores system catalog objects that are common to the whole cluster

stores user tables that are common to the whole cluster

stores WAL logs used for global replication

3 / 20

3. What is the purpose of the public schema?

schema used for heterogeneous replication

restricted schema for postgres internal usage only

no such schema

default schema for user objects

4 / 20

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

pginit

init

postgres

postman

5 / 20

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

vacuum space map

used space map

wal space map

free space map

6 / 20

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

False

True

7 / 20

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

True

False

8 / 20

8. What is another name for the postgres process?

aurora

postmanager

masterprocess

postmaster

9 / 20

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

True

False

10 / 20

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

False

True

11 / 20

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

12 / 20

12. What is the purpose of the template0 database?

Useful for creating development schemas

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

Useful for Postgres support Services to debug issues

No such database

13 / 20

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

System Catalog

Sysasm Catalog

Sysaux Catalog

Sys Catalog

14 / 20

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

True

False

15 / 20

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

False

True

16 / 20

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

pg_system

pg_catalog

pg_class

pg_tables

17 / 20

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

5MB

5GB

1MB

1GB

18 / 20

18. Each Database has its own System Catalog?

True

False

19 / 20

19. TOAST tables reside in a seperate schema?

True

False

20 / 20

20. What is the purpose of the postgres database?

regular database that you can use at your discretion

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

No such database

a template for all the other database

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

Repeatable Read

Read Committed

Serializable

Read Uncommitted

2 / 10

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

True

False

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 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, another transaction modifies this row between these reads and commits the change.

4 / 10

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

False

True

5 / 10

5. Which of the below would best describe a dirty read?

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

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

reading the data directly from file using a text editor such as vi or notepad

reading data direct from memory using pg_dirt

6 / 10

6. Which parameters sets the database default isolation level?

transaction_isolation_level

default_transaction_isolation

active_transaction_isolation

default_isolation_level

7 / 10

7. A phantom read anomaly occurs when?

A transactions inserts a null value into a not null columns and commits

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

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 transaction executes two identical queries returning a set of rows that satisfy a particular condition, while another transaction also queries this same data.

8 / 10

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

ALTER SYSTEM SET ISO=REPEATABLE_READ;

SET ISO=REPEATABLE_READ;

CREATE EXTENSTION REPEATABLE_READ;

BEGIN ISOLATION LEVEL REPEATABLE READ;

9 / 10

9. 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.

Use a single SQL operator

Issues a rollback after the commit to satisfy repeatable read.

10 / 10

10. Which of the below are valid Isolations Levels?

choose 2

Read Committed

Random Scatter

Rollback Read

Serializable

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

redo log

archive log

transaction log

commit log

2 / 10

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

True

False

3 / 10

3. CLOG Pages are never cached in memory?

True

False

4 / 10

4. In Postgres, tables are often referred to as which of the below?

dump

clog

view

heap

5 / 10

5. Indexes values also support multi versioning with several versions of an index value existing at any point in time?

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

False

True

8 / 10

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

False

True

9 / 10

9. psql provides a special mode that allows you to continue a transaction after a failure?

False

True

10 / 10

10. CLOG files are stored in which directory?

PGDATA/pg_xact

PGDATA/pg_commit

PGDATA/pg_clog

PGDATA/clog

Your score is

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