DynamoDB Table Samples | Overview.

DynamoDB Table Samples – Overview.

Scope:

• Into,
• Key concepts for tables,
• Table of Primary Key Types,
• Indexes,
• Data Model,
• Partitioning,
• Sample Designs Orders Table for E-commerce,
• Sample Designs Orders Table for IoT Device Readings,
• Sample Item (json),
• Sample for User Profiles with Flexible Attributes,
• Table of sample of  DynamoDB tables (showing key structures & attributes defined) for client orders,
• Primary Key Design,
• Visual Architecture of DynamoDB Table for Orders,
• How it works,

Intro:

• Amazon DynamoDB is a fully managed NoSQL database service designed for high performance, scalability, and flexibility.

1. Key concepts for tables:

• A collection of items.
• Items are the records; attributes are the fields.
• Every table must have a primary key (either simple or composite).

2. Table of Primary Key Types

Type	Structure	Use Case
Simple Primary Key.	Partition Key only (PK)	When each item is uniquely identified by one attribute
Composite Primary Key.	Partition Key (PK) + Sort Key (SK)	When twtech needs multiple related items per partition, sorted by SK

3. Indexes

• Global Secondary Index (GSI) → Alternate PK/SK for queries unrelated to the main table’s key.
• Local Secondary Index (LSI) → Same PK as the table but a different SK for sorting/filtering.

4. Data Model

• Items are schema-less — attributes can vary between items.
• twtech can store:
• Strings, Numbers, Booleans
• Lists, Maps (nested JSON-like)
• Binary data

5. Partitioning

• DynamoDB automatically splits tables into partitions based on PK (Public Key Key) hash.
• The goal: evenly distribute reads/writes.

A. Sample Designs Orders Table for E-commerce

Primary Key:

• Partition Key (PK): OrderId (string)
• Sort Key (SK): none (simple PK)

Attributes:

• CustomerId
• OrderDate
• Status
• Items (list of maps)
• TotalAmount

GSI1:

• Partition Key (PK): CustomerId
• Sort Key (SK): OrderDate
  

NB:

• Allows: “Get all orders for a customer, sorted by date”

B. Sample Designs Orders Table for IoT Device Readings

Primary Key:

• Partition Key (PK): DeviceId
• Sort Key (SK): Timestamp (ISO 8601)

Attributes:

• Temperature
• Humidity
• BatteryLevel

GSI1:

• Partition Key (PK): Timestamp (for time-based aggregation across devices)
• Sort Key (SK):  none

Sample Item (json)

# json

{

  "DeviceId": "SENSOR-001",

  "Timestamp": "2025-08-11T15:00:00Z",

  "Temperature": 23.5,

  "Humidity": 45,

  "BatteryLevel": 88

}

C. Sample for User Profiles with Flexible Attributes

Primary Key:

• PK: UserId (string)

Attributes:

• Name
• Email
• Preferences (map)
• JoinedDate

NB:

• The is No sort key — each user is a single item.

Sample Item (json):

# json

{

  "UserId": "U1001",

  "Name": "twtech",

  "Email": "twtech671@gmail.com",

  "Preferences": {

    "Theme": "Dark",

    "Notifications": true

  },

  "JoinedDate": "2024-05-12"

}

Table of DynamoDB tables (showing the key structures & attributes defined) for client orders.

Attribute Name	Type	Role	Notes
OrderId.	String.	Partition Key (PK).	Uniquely identifies the order. Example: ORD12345
CustomerId.	String.	Sortable/secondary attribute.	Could be used in a Global Secondary Index (GSI)
OrderDate.	String.	ISO 8601 date/time string.	Example: 2025-08-11T15:30:00Z
Status.	String.	Attribute.	Example values: Pending, Shipped, Delivered
Items.	List<Map>.	Attribute.	Each item has ProductId, Quantity, Price
TotalAmount.	Number.	Attribute.	Example: 149.99

Primary Key Design

• Partition Key: OrderId
• Note, that there is No Sort Key in this example (simple primary key).
• If twtech needs multiple orders per customer sorted by date, it could design:
• Partition Key: CustomerId
• Sort Key: OrderDate

Sample Item (JSON)

# json

{

  "OrderId": "ORD12345",

  "CustomerId": "CUST987",

  "OrderDate": "2025-08-11T15:30:00Z",

  "Status": "Shipped",

  "Items": [

    { "ProductId": "P1001", "Quantity": 2, "Price": 25.00 },

    { "ProductId": "P2005", "Quantity": 1, "Price": 99.99 }

  ],

  "TotalAmount": 149.99

}

Optional Index

If twtech often query by customer:

• Global Secondary Index (GSI)
• Partition Key: CustomerId
• Sort Key: OrderDate
• Lets twtech to query: "All orders for CUST987 in the last 30 days"

Visual Architecture of DynamoDB Table for Orders

Global Secondary Index (GSI1)

•         Partition Key: CustomerId
•         Sort Key: OrderDate

How it works

1.     Partitioning

• DynamoDB distributes items into partitions using the hash value of the Partition Key (OrderId).

2.     GSI (Global Secondary Index)

• The GSI creates an alternate sorted view of the table using CustomerId and OrderDate for fast queries by customer over time.

3.     Scaling

• As data grows, DynamoDB automatically adds partitions behind the scenes.

Sample A – Client Orders Table (E-commerce)

Sample B – IoT Device Readings

Sample C – User Profiles

What This Shows

• Main Table contains the full item data.
• GSI (Global Secondary Index) is a projection:
• Uses a different PK/SK.
• Can contain all attributes (if ProjectionType = ALL) or just keys + select attributes.
• Items in the GSI point back to the same data in the main table.