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 column in system catalogs servers as the Primary Key

oid

obj#

oid#

obj

2 / 20

2. What command is used to create the Postgres cluster?

CreatePGC

CreateCluster

Initialize

StartNewPG

3 / 20

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

PGCORE

PGDATA

PGBASE

PGTIPS

4 / 20

4. What is the purpose of the template1 database?

No such database

database used for temporary tables

regular database that you can use at your discretion

a template for all the other databases

5 / 20

5. What is the purpose of the public schema?

restricted schema for postgres internal usage only

no such schema

default schema for user objects

schema used for heterogeneous replication

6 / 20

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

False

True

7 / 20

7. Which fork is specific for unlogged tables?

Initialization fork

visiblilty map

free space map

Main fork

8 / 20

8. Users should not modify the template0 database

False

True

9 / 20

9. The default Page size is 2k?

False

True

10 / 20

10. What is the purpose of the template0 database?

Useful for creating development schemas

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

No such database

Useful for Postgres support Services to debug issues

11 / 20

11. How does Postgres know which schema to use if not specified?

Directory Path

Search Path

Access Path

Schema Path

12 / 20

12. Tablespaces are used to define physical data layout?

True

False

13 / 20

13. What is the name of the mechanism used to store a row bigger than a page size?

BAKE

GROW

TOAST

BREAD

14 / 20

14. To be able to restore data consistency, Postgres maintains

write-ahead log (WAL)

undo segments (UNDO)

online redo logs (ORL)

rollback segments (RBS)

15 / 20

15. Postgres by default has built in connection pooling abilities?

True

False

16 / 20

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

used space map

wal space map

vacuum space map

free space map

17 / 20

17. What 3 files/forks as a minimum make up a table on disk?

Main fork

table map

visiblilty map

free space map

18 / 20

18. It is the postmasters job to listener for incoming connections?

False

True

19 / 20

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

True

False

20 / 20

20. 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

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

Select more than 1 answer below:

Apply explicit locks

Use a single SQL operator

Issues a rollback after the commit to satisfy repeatable read.

Replace procedural code with declarative one.

2 / 10

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

True

False

3 / 10

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

SOC2

ACID

HIPPA

SAFE

4 / 10

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

False

True

5 / 10

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

True

False

6 / 10

6. 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.

7 / 10

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

True

False

8 / 10

8. What is the default Isolation Level?

Read Uncommitted

Read Committed

Serializable

Repeatable Read

9 / 10

9. Which of the below are valid Isolations Levels?

choose 2

Serializable

Read Committed

Rollback Read

Random Scatter

10 / 10

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

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

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

False

True

2 / 10

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

Each pointer uses 8 bytes

Each pointer uses 4 bytes

stored in PGDATA/itemptr directory

Also know as the pages table of contents

3 / 10

3. indexes do not use row versioning?

True

False

4 / 10

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

False

True

5 / 10

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

True

False

6 / 10

6. Tuples can also be referred to as columns?

True

False

7 / 10

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

True

False

8 / 10

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

True

False

9 / 10

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

magic XID

virtual XID

heap XID

temporary XID

10 / 10

10. index row headers like table row headers contain xmin and xmax fields?

False

True

Your score is

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