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

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

2 / 20

What is the point of the pg_global tablespace?

stores WAL logs used for global replication

stores user tables that are common to the whole cluster

stores system catalog objects that are common to the whole cluster

stores temporary tables that are common to the whole cluster

3 / 20

What is the purpose of the visibility map?

provides the data decryption key

shows referential relationships for tables

shows a page to be vacuumed or frozen

provides an audit trail for the database

4 / 20

What is the default standard size for a fork file?

5MB

1GB

1MB

5GB

5 / 20

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

Choose 2 option

Instance

Quorum

Postgres Server

Aurora

6 / 20

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

True

False

7 / 20

Postgres by default has built in connection pooling abilities?

False

True

8 / 20

Which of below are predefined schemas?

choose 3

pg_schema

information_schema

pg_toast

pg_temp

9 / 20

Which fork keeps track of available space within pages?

wal space map

vacuum space map

free space map

used space map

10 / 20

System Catalog tables begin with which prefix?

dba_

pg_

sys_

cat_

11 / 20

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

12 / 20

What is the purpose of wal writer?

writes WAL entries to disk

collects usage statistics for the instance.

executes checkpoints

flushes dirty pages to disk.

13 / 20

Postgres uses a thread based process model?

False

True

14 / 20

What is the purpose of autovacuum?

Deletes old logs and traces on disk

Rebuilds indexes with b level greater than 2

Performs a backup of WAL logs

Removes stale data from tables and indexes

15 / 20

It is the postmasters job to listener for incoming connections?

True

False

16 / 20

What command is used to create the Postgres cluster?

CreateCluster

StartNewPG

Initialize

CreatePGC

17 / 20

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

System Catalog

Sys Catalog

Sysasm Catalog

Sysaux Catalog

18 / 20

What is the name of the 2 default tablespaces created after initialization?

choose 2

pg_temp

pg_global

pg_tablespace

pg_default

19 / 20

TOAST tables reside in a seperate schema?

True

False

20 / 20

The information_schema schema provides information on Postgres release notes?

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

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

Read Uncommitted

Serializable

Repeatable Read

Read Committed

2 / 10

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

True

False

3 / 10

Which parameters sets the database default isolation level?

default_isolation_level

default_transaction_isolation

active_transaction_isolation

transaction_isolation_level

4 / 10

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

Select more than 1 answer below:

Issues a rollback after the commit to satisfy repeatable read.

Replace procedural code with declarative one.

Apply explicit locks

Use a single SQL operator

5 / 10

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 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 issue a rollback.

A transaction reads one and the same row twice, another transaction modifies this row between these reads and commits the change.

6 / 10

What is the default Isolation Level?

Repeatable Read

Read Committed

Read Uncommitted

Serializable

7 / 10

The SQL standard specifies three isolation levels?

False

True

8 / 10

Which of the below are valid Isolations Levels?

choose 2

Serializable

Read Committed

Random Scatter

Rollback Read

9 / 10

A phantom read anomaly occurs when?

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

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 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.

10 / 10

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

SAFE

HIPPA

ACID

SOC2

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

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

xid

xmin

xtime

xmax

2 / 10

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

False

True

3 / 10

CLOG contains how many bits for each transaction?

4 / 10

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

Each pointer uses 4 bytes

Also know as the pages table of contents

Each pointer uses 8 bytes

stored in PGDATA/itemptr directory

5 / 10

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

True

False

6 / 10

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

True

False

7 / 10

Which 2 items does a Virtual XID consist of?

backend process ID

sequential number

checksum

xmin

8 / 10

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

True

False

9 / 10

UPDATE can be regarded as which 2 separate operations?

INSERT

COMMIT

MERGE

DELETE

10 / 10

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

True

False

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.