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 postgres database?

regular database that you can use at your discretion

a template for all the other database

No such database

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

2 / 20

2. What is the point of the pg_global tablespace?

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

stores system catalog objects that are common to the whole cluster

3 / 20

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

True

False

4 / 20

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

True

False

5 / 20

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

pg_symlinks

pg_tblspc

pg_tablespace

pg_tabspace

6 / 20

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

pg_tables

pg_catalog

pg_system

pg_class

7 / 20

7. The default Page size is 2k?

True

False

8 / 20

8. Which of below are predefined schemas?

choose 2

system

public

pg_catalog

postgres

9 / 20

9. What is the purpose of wal writer?

writes WAL entries to disk

flushes dirty pages to disk.

collects usage statistics for the instance.

executes checkpoints

10 / 20

10. What is a schema?

A memory area used to cache data from LRU chains

Namespace that store all objects of a database

The name used to refer to a super user account

This is the same as a user in Postgres

11 / 20

11. Which fork keeps track of available space within pages?

vacuum space map

wal space map

used space map

free space map

12 / 20

12. pg_catalog schema is used to store system catalog tables?

False

True

13 / 20

13. Postgres server spawns a new backend session for each connection?

True

False

14 / 20

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

PGTIPS

PGCORE

PGDATA

PGBASE

15 / 20

15. What is the purpose of the public schema?

default schema for user objects

schema used for heterogeneous replication

restricted schema for postgres internal usage only

no such schema

16 / 20

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

choose 3

tables

sequences

triggers

indexes

17 / 20

17. A single Postgres Instance can server only one database?

True

False

18 / 20

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

Sysasm Catalog

Sys Catalog

Sysaux Catalog

System Catalog

19 / 20

19. Each tablespaces can only be assigned for use by one database

True

False

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

True

False

2 / 10

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

Select more than 1 answer below:

Apply explicit locks

Replace procedural code with declarative one.

Use a single SQL operator

Issues a rollback after the commit to satisfy repeatable read.

3 / 10

3. Which of the below would best describe a dirty read?

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

reading data direct from memory using pg_dirt

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

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

4 / 10

4. The SQL standard specifies three isolation levels?

False

True

5 / 10

5. What is the default Isolation Level?

Serializable

Repeatable Read

Read Committed

Read Uncommitted

6 / 10

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

choose 3

Read Committed

Read Uncommitted

Serializable

Repeatable Read

7 / 10

7. non-repeatable read anomaly occurs when?

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.

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 issue a rollback.

8 / 10

8. Which parameters sets the database default isolation level?

transaction_isolation_level

default_isolation_level

default_transaction_isolation

active_transaction_isolation

9 / 10

9. Which of the below are valid Isolations Levels?

choose 2

Random Scatter

Rollback Read

Read Committed

Serializable

10 / 10

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

SAFE

ACID

SOC2

HIPPA

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

virtual XID

magic XID

heap XID

temporary XID

2 / 10

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

COMMIT

DELETE

CREATE

INSERT

3 / 10

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

False

True

4 / 10

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

True

False

5 / 10

5. Information about subtransactions is stored under?

PGDATA/pg_subtrans

PGDATA/pg_xid

PGDATA/pg_min

PGDATA/subtrans

6 / 10

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

dump

heap

view

clog

7 / 10

7. Tuples can also be referred to as columns?

False

True

8 / 10

8. UPDATE can be regarded as which 2 separate operations?

INSERT

MERGE

DELETE

COMMIT

9 / 10

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

False

True

10 / 10

10. CLOG files are stored in which directory?

PGDATA/pg_xact

PGDATA/pg_clog

PGDATA/pg_commit

PGDATA/clog

Your score is

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