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 the public schema?

schema used for heterogeneous replication

restricted schema for postgres internal usage only

default schema for user objects

no such schema

2 / 20

2. System Catalog tables begin with which prefix?

sys_

cat_

pg_

dba_

3 / 20

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

5MB

1MB

5GB

1GB

4 / 20

4. If we create a new tablespace which directory will symbolic links be created from?

pg_tblspc

pg_symlinks

pg_tabspace

pg_tablespace

5 / 20

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

pg_tables

pg_class

pg_catalog

pg_system

6 / 20

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

7 / 20

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

True

False

8 / 20

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

Sysasm Catalog

System Catalog

Sysaux Catalog

Sys Catalog

9 / 20

9. What is the purpose of the visibility map?

shows a page to be vacuumed or frozen

shows referential relationships for tables

provides an audit trail for the database

provides the data decryption key

10 / 20

10. What is the purpose of the template1 database?

regular database that you can use at your discretion

a template for all the other databases

database used for temporary tables

No such database

11 / 20

11. Tablespaces are used to define physical data layout?

True

False

12 / 20

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

choose 3

triggers

sequences

indexes

tables

13 / 20

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

Choose 2 option

Quorum

Instance

Aurora

Postgres Server

14 / 20

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

False

True

15 / 20

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

False

True

16 / 20

16. What is the purpose of wal writer?

flushes dirty pages to disk.

executes checkpoints

collects usage statistics for the instance.

writes WAL entries to disk

17 / 20

17. Which of below are predefined schemas?

choose 2

pg_catalog

public

system

postgres

18 / 20

18. What is the purpose of autovacuum?

Deletes old logs and traces on disk

Removes stale data from tables and indexes

Performs a backup of WAL logs

Rebuilds indexes with b level greater than 2

19 / 20

19. What is the purpose of the postgres database?

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

regular database that you can use at your discretion

a template for all the other database

No such database

20 / 20

20. Postgres uses a thread based process model?

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 parameters sets the database default isolation level?

default_transaction_isolation

default_isolation_level

active_transaction_isolation

transaction_isolation_level

2 / 10

2. Which of the below are valid Isolations Levels?

choose 2

Serializable

Rollback Read

Random Scatter

Read Committed

3 / 10

3. What is the default Isolation Level?

Read Uncommitted

Repeatable Read

Read Committed

Serializable

4 / 10

4. 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 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 also queries this same data.

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

5 / 10

5. 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 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.

6 / 10

6. The SQL standard specifies three isolation levels?

True

False

7 / 10

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

choose 3

Repeatable Read

Serializable

Read Uncommitted

Read Committed

8 / 10

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

SOC2

SAFE

ACID

HIPPA

9 / 10

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

True

False

10 / 10

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

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. UPDATE can be regarded as which 2 separate operations?

DELETE

COMMIT

MERGE

INSERT

2 / 10

2. status of a subtransaction is written into CLOG?

True

False

3 / 10

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

False

True

4 / 10

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

True

False

5 / 10

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

False

True

6 / 10

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

True

False

7 / 10

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

DELETE

CREATE

INSERT

COMMIT

8 / 10

8. Information about subtransactions is stored under?

PGDATA/subtrans

PGDATA/pg_xid

PGDATA/pg_subtrans

PGDATA/pg_min

9 / 10

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

True

False

10 / 10

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

xmin

xmax

xmas

xid

Your score is

Cookie	Duration	Description
cookielawinfo-checkbox-analytics	11 months	This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Analytics".
cookielawinfo-checkbox-functional	11 months	The cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional".
cookielawinfo-checkbox-necessary	11 months	This cookie is set by GDPR Cookie Consent plugin. The cookies is used to store the user consent for the cookies in the category "Necessary".
cookielawinfo-checkbox-others	11 months	This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Other.
cookielawinfo-checkbox-performance	11 months	This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Performance".
viewed_cookie_policy	11 months	The cookie is set by the GDPR Cookie Consent plugin and is used to store whether or not user has consented to the use of cookies. It does not store any personal data.