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 point of the pg_global tablespace?

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

stores user tables that are common to the whole cluster

2 / 20

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

pg_class

pg_tables

pg_system

pg_catalog

3 / 20

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

obj#

obj

oid

oid#

4 / 20

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

False

True

5 / 20

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

False

True

6 / 20

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

Sysaux Catalog

Sys Catalog

Sysasm Catalog

System Catalog

7 / 20

7. What is the purpose of the visibility map?

shows referential relationships for tables

provides an audit trail for the database

shows a page to be vacuumed or frozen

provides the data decryption key

8 / 20

8. Which of the below objects can be referred to as relations?

choose 3

tables

indexes

sequences

triggers

9 / 20

9. TOAST tables reside in a seperate schema?

False

True

10 / 20

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

11 / 20

11. What command is used to create the Postgres cluster?

StartNewPG

CreateCluster

Initialize

CreatePGC

12 / 20

12. Postgres uses a thread based process model?

True

False

13 / 20

13. Which of below are predefined schemas?

choose 3

pg_schema

pg_toast

pg_temp

information_schema

14 / 20

14. What is the name of the mechanism used to store a row bigger than a page size?

BAKE

TOAST

GROW

BREAD

15 / 20

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

init

pginit

postgres

postman

16 / 20

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

True

False

17 / 20

17. How does Postgres know which schema to use if not specified?

Directory Path

Access Path

Search Path

Schema Path

18 / 20

18. System Catalog tables begin with which prefix?

dba_

sys_

cat_

pg_

19 / 20

19. Files are logically split into pages?

False

True

20 / 20

20. What is another name for the postgres process?

postmaster

masterprocess

aurora

postmanager

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

True

False

2 / 10

2. non-repeatable read anomaly occurs when?

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, 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 once and modifies this row and commits the change.

3 / 10

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

SET ISO=REPEATABLE_READ;

CREATE EXTENSTION REPEATABLE_READ;

BEGIN ISOLATION LEVEL REPEATABLE READ;

ALTER SYSTEM SET ISO=REPEATABLE_READ;

4 / 10

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

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

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

reading data direct from memory using pg_dirt

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

6 / 10

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

choose 3

Serializable

Read Uncommitted

Repeatable Read

Read Committed

7 / 10

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

False

True

8 / 10

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

True

False

9 / 10

9. A phantom read anomaly occurs when?

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.

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

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

10 / 10

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

Read Uncommitted

Read Committed

Repeatable 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. index row headers like table row headers contain xmin and xmax fields?

False

True

2 / 10

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

False

True

3 / 10

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

True

False

4 / 10

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

choose 2

page header

undo segment

free space

flashback block

5 / 10

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

pagedetect

pageheadinfo

pagesize

pageinspect

6 / 10

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

False

True

7 / 10

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

False

True

8 / 10

8. CLOG Pages are never cached in memory?

True

False

9 / 10

9. CLOG files are stored in which directory?

PGDATA/pg_xact

PGDATA/pg_clog

PGDATA/clog

PGDATA/pg_commit

10 / 10

10. Information about subtransactions is stored under?

PGDATA/pg_xid

PGDATA/pg_min

PGDATA/pg_subtrans

PGDATA/subtrans

Your score is

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