On-demand backups in DynamoDB - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is an on-demand backup in DynamoDB?

An on-demand backup is a manual snapshot of your DynamoDB table data at a specific point in time. It lets you save the current state of your table without affecting its performance.

beginner

How do on-demand backups affect the performance of a DynamoDB table?

On-demand backups do not impact the performance or availability of the DynamoDB table. You can continue to read and write data while the backup is being created.

beginner

Can you restore a DynamoDB table from an on-demand backup?

Yes, you can restore a new DynamoDB table from an on-demand backup. The restored table will have the data exactly as it was when the backup was taken.

intermediate

What is the retention period for on-demand backups in DynamoDB?

On-demand backups are retained until you explicitly delete them. There is no automatic expiration, so you control how long backups are kept.

intermediate

How do you create an on-demand backup using AWS CLI for a DynamoDB table named 'Users'?

You run the command:
aws dynamodb create-backup --table-name Users --backup-name UsersBackup
This creates a backup named 'UsersBackup' of the 'Users' table.

What happens to your DynamoDB table's availability during an on-demand backup?

A The table becomes unavailable until backup completes

B Writes are blocked but reads continue

C The table is read-only during backup

D The table remains fully available for reads and writes

On-demand backups do not affect table availability; reads and writes continue normally.

How long are on-demand backups stored in DynamoDB by default?

A 30 days

B Until manually deleted

C 7 days

D 90 days

On-demand backups remain until you delete them; there is no automatic expiration.

Which AWS CLI command creates an on-demand backup for a DynamoDB table?

A aws dynamodb backup-table

B aws dynamodb start-backup

C aws dynamodb create-backup

D aws dynamodb snapshot-table

The correct command is 'aws dynamodb create-backup' to create an on-demand backup.

Can you restore a DynamoDB table from an on-demand backup to a different table name?

A Yes, you can restore to a new table name

B Only if the backup is less than 7 days old

C Only if the table is empty

D No, you must restore to the original table name

You can restore from an on-demand backup to a new table with a different name.

Which of the following is true about on-demand backups in DynamoDB?

A They are manual snapshots created when you request

B They impact table performance during backup

C They automatically back up data every hour

D They delete old backups automatically

On-demand backups are manual snapshots created when you request them.

Explain what an on-demand backup is in DynamoDB and how it affects your table's availability.

Think about when you create the backup and what happens to your table during that time.

Describe the process and commands to create and restore an on-demand backup in DynamoDB.

Focus on the AWS CLI commands and what parameters you need.

Practice

1. What is the main purpose of on-demand backups in DynamoDB?

easy

A. To delete old data from the table

B. To automatically scale the table capacity

C. To encrypt data during transfer

D. To save a copy of your table data at any time for recovery

Solution

1. Step 1: Understand what on-demand backups do

   On-demand backups let you save your DynamoDB table data whenever you want.

2. Step 2: Identify the main purpose

   The main goal is to protect data and allow recovery if needed.

3. Final Answer:

   To save a copy of your table data at any time for recovery -> Option D

4. Quick Check:

   On-demand backups = save data anytime [OK]

Hint: Backups save data copies for recovery anytime [OK]

Common Mistakes:

• Confusing backups with scaling features
• Thinking backups delete data
• Mixing encryption with backup purpose

2. Which AWS CLI command is used to create an on-demand backup of a DynamoDB table?

easy

A. aws dynamodb backup-table

B. aws dynamodb start-backup

C. aws dynamodb create-backup

D. aws dynamodb save-backup

Solution

1. Step 1: Recall the correct AWS CLI command for backups

   The official command to create an on-demand backup is create-backup.

2. Step 2: Match the command with options

   Only aws dynamodb create-backup matches the exact AWS CLI syntax.

3. Final Answer:

   aws dynamodb create-backup -> Option C

4. Quick Check:

   Command to create backup = create-backup [OK]

Hint: Remember 'create-backup' for making backups [OK]

Common Mistakes:

• Using incorrect command names like start-backup
• Confusing backup commands with table creation
• Adding extra words not in AWS CLI syntax

3. What will happen if you run this AWS CLI command?

aws dynamodb create-backup --table-name Users --backup-name UsersBackup1

medium

A. It creates a backup named 'UsersBackup1' of the 'Users' table

B. It deletes the 'Users' table

C. It lists all backups of the 'Users' table

D. It restores the 'Users' table from a backup

Solution

1. Step 1: Analyze the command parameters

   The command uses create-backup with a table name and backup name.

2. Step 2: Understand the command effect

   This command creates a new backup of the specified table with the given backup name.

3. Final Answer:

   It creates a backup named 'UsersBackup1' of the 'Users' table -> Option A

4. Quick Check:

   create-backup + table + backup name = new backup [OK]

Hint: create-backup command makes a new backup copy [OK]

Common Mistakes:

• Thinking it deletes or restores the table
• Confusing create-backup with list-backups
• Assuming it modifies table data

4. You tried to create a backup with this command:

aws dynamodb create-backup --table-name Orders

Why did it fail?

medium

A. Table name 'Orders' does not exist

B. Missing the required --backup-name parameter

C. You need to use 'start-backup' instead of 'create-backup'

D. Backups are not supported for DynamoDB tables

Solution

1. Step 1: Check the command syntax

   The command is missing the --backup-name parameter which is required.

2. Step 2: Understand AWS CLI requirements

   Without a backup name, the command cannot create a backup and will fail.

3. Final Answer:

   Missing the required --backup-name parameter -> Option B

4. Quick Check:

   create-backup needs backup name [OK]

Hint: Always include --backup-name when creating backups [OK]

Common Mistakes:

• Assuming table name alone is enough
• Using wrong command like start-backup
• Believing backups are unsupported

5. You want to create an on-demand backup for a table named 'Products' and then restore it if needed. Which sequence of AWS CLI commands is correct?

hard

A. aws dynamodb create-backup --table-name Products --backup-name ProdBackup1aws dynamodb restore-table-from-backup --target-table-name ProductsRestored --backup-arn

B. aws dynamodb backup-table --table-name Productsaws dynamodb restore-table --table-name ProductsRestored

C. aws dynamodb start-backup --table Productsaws dynamodb recover-table --table ProductsRestored

D. aws dynamodb create-backup --table Products --backup-name ProdBackup1aws dynamodb restore-backup --table ProductsRestored --backup-name ProdBackup1

Solution

1. Step 1: Identify correct backup creation command

   The correct command to create a backup is create-backup with table and backup names.

2. Step 2: Identify correct restore command

   To restore, use restore-table-from-backup with target table name and backup ARN.

3. Step 3: Verify options

   Only aws dynamodb create-backup --table-name Products --backup-name ProdBackup1
   aws dynamodb restore-table-from-backup --target-table-name ProductsRestored --backup-arn uses the correct commands and parameters for both backup and restore.

4. Final Answer:

   Use create-backup then restore-table-from-backup with backup ARN -> Option A

5. Quick Check:

   Backup with create-backup, restore with restore-table-from-backup [OK]

Hint: Backup with create-backup, restore with restore-table-from-backup [OK]

Common Mistakes:

• Using wrong commands like start-backup or backup-table
• Missing backup ARN in restore command
• Confusing restore parameters