On-demand backups in DynamoDB - Step-by-Step Execution

Concept Flow - On-demand backups

Start Backup Request

↓

Check Table Exists?

No→Error: Table Not Found

Yes↓

Create Backup

↓

Backup Status: CREATING

↓

Backup Status: AVAILABLE

↓

Backup Ready for Use

The flow starts with a backup request, checks if the table exists, creates the backup, waits for it to become available, then the backup is ready to use.

Execution Sample

DynamoDB

aws dynamodb create-backup --table-name Music --backup-name MusicBackup1

This command creates an on-demand backup of the 'Music' table named 'MusicBackup1'.

Execution Table

Step	Action	Input	Output	Status
1	Receive backup request	Table: Music, BackupName: MusicBackup1	Request accepted	Pending
2	Check if table exists	Table: Music	Table found	Pending
3	Start backup creation	Table: Music	Backup creation started	CREATING
4	Wait for backup completion	Backup: MusicBackup1	Backup status updated	CREATING
5	Backup creation complete	Backup: MusicBackup1	Backup available	AVAILABLE
6	Backup ready	Backup: MusicBackup1	Backup can be used	AVAILABLE

💡 Backup status is AVAILABLE, so the on-demand backup is complete and ready.

Variable Tracker

Variable	Start	After Step 2	After Step 3	After Step 5	Final
TableExists	Unknown	True	True	True	True
BackupStatus	None	None	CREATING	AVAILABLE	AVAILABLE

Key Moments - 3 Insights

Why do we check if the table exists before creating a backup?

Because if the table does not exist (see Step 2 in execution_table), the backup cannot be created and the process stops with an error.

What does the backup status 'CREATING' mean?

It means the backup process has started but is not finished yet (see Steps 3 and 4). The backup is not usable until the status changes to 'AVAILABLE'.

When is the backup ready to use?

When the backup status is 'AVAILABLE' (see Step 5 and 6), the backup is complete and can be restored or copied.

Visual Quiz - 3 Questions

Look at the execution_table, what is the backup status after Step 3?

A CREATING

B AVAILABLE

C PENDING

D FAILED

💡 Hint

Check the 'Status' column in the row for Step 3 in the execution_table.

At which step does the backup become ready for use?

A Step 5

B Step 6

C Step 4

D Step 2

💡 Hint

Look at the 'Action' and 'Status' columns in the execution_table for when the backup is 'AVAILABLE' and ready.

If the table does not exist, what happens according to the concept_flow?

A Backup is created anyway

B Backup status is AVAILABLE

C Error: Table Not Found

D Backup creation starts but fails later

💡 Hint

Refer to the decision after 'Check Table Exists?' in the concept_flow diagram.

Concept Snapshot

On-demand backups in DynamoDB:
- Use create-backup command with table and backup names.
- System checks if the table exists first.
- Backup status moves from CREATING to AVAILABLE.
- Backup is ready to use only when AVAILABLE.
- Errors occur if table not found.

Full Transcript

On-demand backups in DynamoDB start when you request a backup for a specific table. The system first checks if the table exists. If it does not, an error stops the process. If the table exists, the backup creation begins and the status is 'CREATING'. Once the backup is complete, the status changes to 'AVAILABLE', meaning the backup is ready to use. This process ensures your data is safely saved and can be restored later if needed.

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