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

Which fork contains the actual table data?

Main fork

visiblilty map

table map

free space map

2 / 20

What is the process first launched at server start?

postgres

postman

init

pginit

3 / 20

What is the purpose of autovacuum?

Removes stale data from tables and indexes

Deletes old logs and traces on disk

Performs a backup of WAL logs

Rebuilds indexes with b level greater than 2

4 / 20

What is the purpose of wal writer?

flushes dirty pages to disk.

writes WAL entries to disk

executes checkpoints

collects usage statistics for the instance.

5 / 20

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

True

False

6 / 20

The information_schema schema provides information on Postgres release notes?

False

True

7 / 20

What is another name for the postgres process?

masterprocess

postmanager

postmaster

aurora

8 / 20

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

9 / 20

System Catalog tables begin with which prefix?

pg_

cat_

sys_

dba_

10 / 20

Files are logically split into pages?

True

False

11 / 20

Tablespaces are used to define physical data layout?

False

True

12 / 20

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

13 / 20

What is the point of the pg_global tablespace?

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

stores WAL logs used for global replication

14 / 20

A schema can belong to more than one database?

True

False

15 / 20

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

pg_tables

pg_class

pg_catalog

pg_system

16 / 20

Which of below are predefined schemas?

choose 2

system

public

pg_catalog

postgres

17 / 20

What is the purpose of the postgres database?

No such 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

18 / 20

Which of below are predefined schemas?

choose 3

pg_schema

information_schema

pg_temp

pg_toast

19 / 20

pg_catalog schema is used to store system catalog tables?

True

False

20 / 20

To be able to restore data consistency, Postgres maintains

undo segments (UNDO)

rollback segments (RBS)

write-ahead log (WAL)

online redo logs (ORL)

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

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

False

True

2 / 10

The SQL standard specifies three isolation levels?

True

False

3 / 10

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

False

True

4 / 10

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

False

True

5 / 10

Which of the below would best describe a dirty read?

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

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 data direct from memory using pg_dirt

6 / 10

What is the default Isolation Level?

Serializable

Read Committed

Repeatable Read

Read Uncommitted

7 / 10

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

choose 3

Read Uncommitted

Read Committed

Serializable

Repeatable Read

8 / 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 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.

9 / 10

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

ACID

HIPPA

SOC2

SAFE

10 / 10

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

False

True

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

CLOG Pages are never cached in memory?

False

True

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?

magic XID

virtual XID

temporary XID

heap XID

4 / 10

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

xmax

xmas

xmin

xid

5 / 10

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

True

False

6 / 10

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

True

False

7 / 10

status of a subtransaction is written into CLOG?

False

True

8 / 10

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

commit log

redo log

transaction log

archive log

9 / 10

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

True

False

10 / 10

Tuples can also be referred to as columns?

True

False

Your score is

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