Data modeling is one of the most important steps ensuring performance and scalability of Cassandra-powered applications. The existing Chebotko data modeling methodology lays out important data modeling principles, rules and patterns to design a conceptual, logical and physical data models. While this approach enables rigorous and sound schema design, it requires specialized training and experience. To dramatically reduce time, simplify and streamline the Cassandra database design process, we develop an online tool that automates the most complex, error-prone, and time-consuming data modeling tasks: conceptual-to-logical mapping, logical-to-physical mapping, and CQL generation. In this talk, using real life examples from the IoT domain, we demonstrate how to design correct and efficient database schemas for Cassandra. First, we use our tool, called KDM, to design a conceptual data model and specify application access patterns. Second, we demonstrate how KDM generates a logical data model that is visualized using Chebotko diagram notation. Third, we explain how to configure a logical data model and automatically generate a physical data model. Fourth, we showcase how KDM generates a CQL script for instantiating a physical data model in Cassandra. Finally, we discuss best practices for Cassandra data modeling with KDM. The KDM tool is available for free at kdm.dataview.org and is used by many in industry and academia. Andrey Kashlev - Wayne State University Andrey Kashlev is a PhD candidate in big data, working in the Department of Computer Science at Wayne State University. His research focuses on big data, including data modeling for NoSQL, big data workflows, and provenance management. He has published numerous research articles in peer-reviewed international journals and conferences, including IEEE Transactions on Services Computing, Data and Knowledge Engineering, International Journal of Computers and Their Applications, and the IEEE International Congress on Big Data.

1. World’s Best Data Modeling Tool
for Apache Cassandra
1© 2015. All Rights Reserved.
Artem ChebotkoAndrey Kashlev

2. 1 Cassandra Data Modeling Methodology
2 The KDM Tool
3 Live Demo: IoT
4 Live Demo: Media Cataloguing
5 Future Work
2© 2015. All Rights Reserved.

3. Data Modeling Process
• Data requirements
• Application requirements
• Schema Design
• Optimization
3© 2015. All Rights Reserved.

4. Cassandra Data Modeling Methodology
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Conceptual
Data Model
Application
Workflow
Logical
Data Model
Physical
Data Model
Mapping Optimization

5. Methodology Models
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Model Representation
Conceptual Data Model ERD
Application Workflow Model Graph
Logical Data Model Chebotko Diagram
Physical Data Model Chebotko Diagram, CQL

6. Methodology Protocols
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• Conceptual-to-logical mapping
– Mapping rules
– Mapping patterns
• Physical optimizations
– Partition size analysis
– Duplication factor analysis
– Keys, aggregation, transactions, …

7. Example
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SELECT timestamp, value FROM …
WHERE location = ? AND parameter = ? AND timestamp > ?
ORDER BY timestamp DESC
n
parameter value
1
timestampid location
Sensor Measurementrecords

8. sensor_data
location K
parameter K
timestamp C↓
id C↑
value
1
Example
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SELECT timestamp, value FROM …
WHERE location = ? AND parameter = ?
AND timestamp > ?
ORDER BY timestamp DESC
n
parameter value
1
timestampid location
Sensor Measurementrecords
Mapping Entity and Relationship Types

9. sensor_data
location K
parameter K
timestamp C↓
id C↑
value
sensor_data
location K
parameter K
timestamp C↓
id C↑
value
1 2
Example
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SELECT timestamp, value FROM …
WHERE location = ? AND parameter = ?
AND timestamp > ?
ORDER BY timestamp DESC
n
parameter value
1
timestampid location
Sensor Measurementrecords
Mapping Equality Search Atributes

10. sensor_data
location K
parameter K
timestamp C↓
id C↑
value
sensor_data
location K
parameter K
timestamp C↓
id C↑
value
sensor_data
location K
parameter K
timestamp C↑
id C↑
value
1 2 3
Example
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SELECT timestamp, value FROM …
WHERE location = ? AND parameter = ?
AND timestamp > ?
ORDER BY timestamp DESC
n
parameter value
1
timestampid location
Sensor Measurementrecords
Mapping Inequality Search Attributes

11. sensor_data
location K
parameter K
timestamp C↓
id C↑
value
sensor_data
location K
parameter K
timestamp C↓
id C↑
value
sensor_data
location K
parameter K
timestamp C↑
id C↑
value
sensor_data
location K
parameter K
timestamp C↓
id C↑
value
1 2 3 4
Example
© 2015. All Rights Reserved. 11
SELECT timestamp, value FROM …
WHERE location = ? AND parameter = ?
AND timestamp > ?
ORDER BY timestamp DESC
n
parameter value
1
timestampid location
Sensor Measurementrecords
Mapping Ordering Attributes

12. sensor_data
location K
parameter K
timestamp C↓
id C↑
value
sensor_data
location K
parameter K
timestamp C↓
id C↑
value
sensor_data
location K
parameter K
timestamp C↓
id C↑
value
sensor_data
location K
parameter K
timestamp C↑
id C↑
value
sensor_data
location K
parameter K
timestamp C↓
id C↑
value
1 2 3 4 5
Example
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SELECT timestamp, value FROM …
WHERE location = ? AND parameter = ?
AND timestamp > ?
ORDER BY timestamp DESC
n
parameter value
1
timestampid location
Sensor Measurementrecords
Mapping Key Attributes

13. Methodology Pros and Cons
Correctness
Completeness
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Complexity
Time investment

14. Human Errors Happen …
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15. Automation
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Complexity
Time investment
Human Error

16. 1 Cassandra Data Modeling Methodology
2 The KDM Tool
3 Live Demo: IoT
4 Live Demo: Media Cataloguing
5 Future Work
16© 2015. All Rights Reserved.

17. The KDM Tool
• Streamlines the methodology
• Guides the user
• Automates data modeling tasks:
– Conceptual-to-logical mapping
– Physical optimization
– CQL generation
17© 2015. All Rights Reserved.

18. KDM Automation Workflow
18© 2015. All Rights Reserved.

19. KDM Automation Workflow
19© 2015. All Rights Reserved.
Design
Conceptual
Data Model
Step1
Solution
architect

20. KDM Automation Workflow
20© 2015. All Rights Reserved.
Design
Conceptual
Data Model
Specify
Access
Patterns
Solution
architect
Step1 Step2
Solution
architect

21. KDM Automation Workflow
21© 2015. All Rights Reserved.
Design
Conceptual
Data Model
Specify
Access
Patterns
Generate
Logical
Data
Models
KDM
Solution
architect
Step1 Step2 Automated
Solution
architect

22. KDM Automation Workflow
22© 2015. All Rights Reserved.
Design
Conceptual
Data Model
Specify
Access
Patterns
Generate
Logical
Data
Models
Select
Logical
Data
Model
KDM
Solution
architect
Step1 Step2 Step3Automated
Solution
architect
Solution
architect

23. KDM Automation Workflow
23© 2015. All Rights Reserved.
Design
Conceptual
Data Model
Specify
Access
Patterns
Generate
Logical
Data
Models
Select
Logical
Data
Model
Generate
Physical
Data
Model
KDM
Solution
architect
Step1 Step2 Step3Automated Automated
Solution
architect
Solution
architect
KDM

24. KDM Automation Workflow
24© 2015. All Rights Reserved.
Design
Conceptual
Data Model
Specify
Access
Patterns
Generate
Logical
Data
Models
Select
Logical
Data
Model
Generate
Physical
Data
Model
Configure
Physical
Data
Model
KDM
Solution
architect
Step1 Step2 Step3 Step4Automated Automated
Solution
architect
Solution
architect
Solution
architect
KDM

25. KDM Automation Workflow
25© 2015. All Rights Reserved.
Design
Conceptual
Data Model
Specify
Access
Patterns
Generate
Logical
Data
Models
Select
Logical
Data
Model
Generate
Physical
Data
Model
Configure
Physical
Data
Model
Generate
Physical
Schema
KDM
Solution
architect
Step1 Step2 Step3 Step4Automated Automated Automated
Solution
architect
Solution
architect
Solution
architect
KDM KDM

26. KDM Automation Workflow
26© 2015. All Rights Reserved.
Design
Conceptual
Data Model
Specify
Access
Patterns
Generate
Logical
Data
Models
Select
Logical
Data
Model
Generate
Physical
Data
Model
Configure
Physical
Data
Model
Generate
Physical
Schema
Download
CQL
Script
KDM
Solution
architect
Step1 Step2 Step3 Step4 Step5Automated Automated Automated
Solution
architect
Solution
architect
Solution
architect
Solution
architect
KDM KDM

27. 1 Cassandra Data Modeling Methodology
2 The KDM Tool
3 Live Demo: IoT
4 Live Demo: Media Cataloguing
5 Future Work
27© 2015. All Rights Reserved.

28. 28

29. 1 Cassandra Data Modeling Methodology
2 The KDM Tool
3 Live Demo: IoT
4 Live Demo: Media Cataloguing
5 Future Work
29© 2015. All Rights Reserved.

30. © 2015. All Rights Reserved. 30

31. 31© 2015. All Rights Reserved.
• KDM:
– automates most complex tasks
– eliminates human error
– simplifies data modeling
– guides
– is a general purpose tool
Summary

32. 32© 2015. All Rights Reserved.
• build new data models
• verify existing data models
• teach/learn data modeling
How Can KDM Help You?

33. 1 Cassandra Data Modeling Methodology
2 The KDM Tool
3 Live Demo: IoT
4 Live Demo: Media Cataloguing
5 Future Work
33© 2015. All Rights Reserved.

34. Future Work
• Materialized views
© 2015. All Rights Reserved. 34

35. Future Work
• Materialized views
• User Defined Types
© 2015. All Rights Reserved. 35

36. Future Work
• Materialized views
• User Defined Types
• Analysis and physical optimization
© 2015. All Rights Reserved. 36

37. Future Work
• Materialized views
• User Defined Types
• Analysis and physical optimization
• Support for application workflow design
© 2015. All Rights Reserved. 37

38. Future Work
• Materialized views
• User Defined Types
• Analysis and physical optimization
• Support for application workflow design
• Support for Chebotko Diagrams
© 2015. All Rights Reserved. 38

39. Sign up for KDM – it’s FREE!
• KDM: kdm.dataview.org
• Methodology: academy.datastax.com
• Planet Cassandra blog posts:
– KDM: An Automated Data Modeling Tool for Apache
Cassandra, Pt. 1, Pt. 2
• Artem Chebotko, Andrey Kashlev, Shiyong Lu,
“A Big Data Modeling Methodology for Apache Cassandra”,
IEEE International Congress on Big Data, 2015.
© 2015. All Rights Reserved. 39

40. Acknowledgements
• Andrey Kashlev would like to thank:
– Dr. Shiyong Lu
– Anthony Piazza
• Artem Chebotko would like to thank:
– Anthony Piazza
– Patrick McFadin
– Jonathan Ellis
– Tim Berglund
© 2015. All Rights Reserved. 40

41. Thank you