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

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

choose 2

pg_tablespace

pg_global

pg_default

pg_temp

2 / 20

What is the purpose of the visibility map?

provides an audit trail for the database

shows a page to be vacuumed or frozen

provides the data decryption key

shows referential relationships for tables

3 / 20

What is the name of the directory that contains the files related to the Postgres cluster?

PGBASE

PGCORE

PGDATA

PGTIPS

4 / 20

A single Postgres Instance can server only one database?

False

True

5 / 20

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

False

True

6 / 20

Postgres uses a thread based process model?

False

True

7 / 20

A schema can belong to more than one database?

False

True

8 / 20

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

True

False

9 / 20

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

10 / 20

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

11 / 20

Postgres by default has built in connection pooling abilities?

True

False

12 / 20

What is the purpose of the template0 database?

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

Useful for Postgres support Services to debug issues

Useful for creating development schemas

No such database

13 / 20

TOAST tables reside in a seperate schema?

False

True

14 / 20

The information_schema schema provides information on Postgres release notes?

True

False

15 / 20

Each Database has its own System Catalog?

True

False

16 / 20

What column in system catalogs servers as the Primary Key

oid#

oid

obj#

obj

17 / 20

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

18 / 20

What is the process first launched at server start?

init

postgres

postman

pginit

19 / 20

Who is the Author of the Postgres 14 Internals book?

Dan Brown

Egor Rogov

Sam Altman

Paul Sammy

20 / 20

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

System Catalog

Sys Catalog

Sysaux Catalog

Sysasm Catalog

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

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

HIPPA

ACID

SOC2

SAFE

2 / 10

The SQL standard specifies three isolation levels?

True

False

3 / 10

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

True

False

4 / 10

Which parameters sets the database default isolation level?

default_isolation_level

transaction_isolation_level

default_transaction_isolation

active_transaction_isolation

5 / 10

What is the default Isolation Level?

Read Committed

Repeatable Read

Serializable

Read Uncommitted

6 / 10

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.

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

7 / 10

Which of the below would best describe a dirty read?

reading data direct from memory using pg_dirt

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

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

8 / 10

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 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.

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

9 / 10

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.

Use a single SQL operator

Issues a rollback after the commit to satisfy repeatable read.

Apply explicit locks

10 / 10

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

choose 3

Repeatable Read

Serializable

Read Uncommitted

Read Committed

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

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

True

False

2 / 10

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

False

True

3 / 10

If a transaction is read only which kind of Transaction ID is it allocated?

heap XID

magic XID

virtual XID

temporary XID

4 / 10

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

True

False

5 / 10

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

True

False

6 / 10

Tuples can also be referred to as columns?

True

False

7 / 10

CLOG Pages are never cached in memory?

False

True

8 / 10

CLOG files are stored in which directory?

PGDATA/pg_xact

PGDATA/pg_commit

PGDATA/clog

PGDATA/pg_clog

9 / 10

Which function can we use to find the current transaction ID?

pg_current_id()

pg_current_xmin_id()

pg_current_xact_id()

pg_current_commit_id()

10 / 10

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

heap

dump

view

clog

Your score is

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