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. System Catalog tables begin with which prefix?

pg_

dba_

cat_

sys_

2 / 20

2. The information_schema schema provides information on Postgres release notes?

True

False

3 / 20

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

Sys Catalog

Sysaux Catalog

Sysasm Catalog

System Catalog

4 / 20

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

Choose 2 option

Quorum

Postgres Server

Aurora

Instance

5 / 20

5. What is the purpose of wal writer?

collects usage statistics for the instance.

executes checkpoints

writes WAL entries to disk

flushes dirty pages to disk.

6 / 20

6. What is the purpose of the visibility map?

provides an audit trail for the database

shows a page to be vacuumed or frozen

shows referential relationships for tables

provides the data decryption key

7 / 20

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

False

True

8 / 20

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

pg_class

pg_tables

pg_catalog

pg_system

9 / 20

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

10 / 20

10. Each Database has its own System Catalog?

False

True

11 / 20

11. Files are logically split into pages?

True

False

12 / 20

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

Main fork

table map

free space map

visiblilty map

13 / 20

13. What is the purpose of the public schema?

restricted schema for postgres internal usage only

default schema for user objects

schema used for heterogeneous replication

no such schema

14 / 20

14. Which of below are predefined schemas?

choose 3

pg_toast

pg_schema

pg_temp

information_schema

15 / 20

15. What is the point of the pg_global tablespace?

stores temporary tables that are common to the whole cluster

stores WAL logs used for global replication

stores system catalog objects that are common to the whole cluster

stores user tables that are common to the whole cluster

16 / 20

16. What is the purpose of the postgres database?

No such database

a template for all the other database

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

regular database that you can use at your discretion

17 / 20

17. What is the default standard size for a fork file?

1MB

5GB

1GB

5MB

18 / 20

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

True

False

19 / 20

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

Search Path

Access Path

Directory Path

Schema Path

20 / 20

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

True

False

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 is the default Isolation Level?

Read Uncommitted

Read Committed

Repeatable Read

Serializable

2 / 10

2. 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 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 and commits the change.

3 / 10

3. Which of the below are valid Isolations Levels?

choose 2

Read Committed

Random Scatter

Serializable

Rollback Read

4 / 10

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

ACID

SAFE

HIPPA

SOC2

5 / 10

5. A phantom read anomaly occurs when?

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

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.

6 / 10

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

True

False

7 / 10

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

choose 3

Serializable

Repeatable Read

Read Committed

Read Uncommitted

8 / 10

8. The SQL standard specifies three isolation levels?

True

False

9 / 10

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

False

True

10 / 10

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

True

False

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. CLOG files are stored in which directory?

PGDATA/pg_xact

PGDATA/pg_commit

PGDATA/clog

PGDATA/pg_clog

2 / 10

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

commit log

transaction log

redo log

archive log

3 / 10

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

temporary XID

magic XID

heap XID

virtual XID

4 / 10

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

True

False

5 / 10

5. The page header is located in the highest address?

False

True

6 / 10

6. Page header sizes can be easily displayed using the <choose from answers> extension

pagesize

pagedetect

pageinspect

pageheadinfo

7 / 10

7. Which 2 items does a Virtual XID consist of?

sequential number

checksum

xmin

backend process ID

8 / 10

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

clog

dump

heap

view

9 / 10

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

True

False

10 / 10

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

True

False

Your score is

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