1) Apache Cassandra in term of CAP Theorem
2) What makes Apache Cassandra "Available"?
3) How Apache Cassandra ensures data consistency?
4) Cassandra advantages and disadvantages
5) Frameworks/libraries to access Apache Cassandra + performance comparison
Basic Introduction to Cassandra with Architecture and strategies.
with big data challenge. What is NoSQL Database.
The Big Data Challenge
The Cassandra Solution
The CAP Theorem
The Architecture of Cassandra
The Data Partition and Replication
Basic Introduction to Cassandra with Architecture and strategies.
with big data challenge. What is NoSQL Database.
The Big Data Challenge
The Cassandra Solution
The CAP Theorem
The Architecture of Cassandra
The Data Partition and Replication
Apache Cassandra is a highly scalable second-generation distributed database, bringing together Dynamo's fully distributed design and Bigtable's ColumnFamily-based data model.
This presentation, given at FOSDEM in 2010, provides a brief summary of cassandra's history, a high-level overview of the architecture and data model, and showcases some real life use-cases.
What is Apache Cassandra? | Apache Cassandra Tutorial | Apache Cassandra Intr...Edureka!
** Apache Cassandra Certification Training: https://www.edureka.co/cassandra **
This Edureka tutorial on "What is Apache Cassandra" will give you a detailed introduction to the NoSQL database Apache Cassandra and it's various features. Learn why Cassandra is preferred over other Databases. You will also learn about the various elements of Cassandra Database with an interactive Industry based Use Case.
C* Summit 2013: Cassandra at eBay Scale by Feng Qu and Anurag JambhekarDataStax Academy
We have seen rapid adoption of C* at eBay in past two years. We have made tremendous efforts to integrate C* into existing database platforms, including Oracle, MySQL, Postgres, MongoDB, XMP etc.. We also scale C* to meet business requirement and encountered technical challenges you only see at eBay scale, 100TB data on hundreds of nodes. We will share our experience of deployment automation, managing, monitoring, reporting for both Apache Cassandra and DataStax enterprise.
What Every Developer Should Know About Database Scalabilityjbellis
Replication. Partitioning. Relational databases. Bigtable. Dynamo. There is no one-size-fits-all approach to scaling your database, and the CAP theorem proved that there never will be. This talk will explain the advantages and limits of the approaches to scaling traditional relational databases, as well as the tradeoffs made by the designers of newer distributed systems like Cassandra. These slides are from Jonathan Ellis's OSCON 09 talk: http://en.oreilly.com/oscon2009/public/schedule/detail/7955
Cassandra is a highly scalable, eventually consistent, distributed, structured columnfamily store with no single points of failure, initially open-sourced by Facebook and now part of the Apache Incubator. These slides are from Jonathan Ellis's OSCON 09 talk: http://en.oreilly.com/oscon2009/public/schedule/detail/7975
Apache Cassandra operations have the reputation to be simple on single datacenter deployments and / or low volume clusters but they become way more complex on high latency multi-datacenter clusters with high volume and / or high throughout: basic Apache Cassandra operations such as repairs, compactions or hints delivery can have dramatic consequences even on a healthy high latency multi-datacenter cluster.
In this presentation, Julien will go through Apache Cassandra mutli-datacenter concepts first then show multi-datacenter operations essentials in details: bootstrapping new nodes and / or datacenter, repairs strategy, Java GC tuning, OS tuning, Apache Cassandra configuration and monitoring.
Based on his 3 years experience managing a multi-datacenter cluster against Apache Cassandra 2.0, 2.1, 2.2 and 3.0, Julien will give you tips on how to anticipate and prevent / mitigate issues related to basic Apache Cassandra operations with a multi-datacenter cluster.
About the Speaker
Julien Anguenot VP Software Engineering, iland Internet Solutions, Corp
Julien currently serves as iland's Vice President of Software Engineering. Prior to joining iland, Mr. Anguenot held tech leadership positions at several open source content management vendors and tech startups in Europe and in the U.S. Julien is a long time Open Source software advocate, contributor and speaker: Zope, ZODB, Nuxeo contributor, Zope and OpenStack foundations member, his talks includes Apache Con, Cassandra summit, OpenStack summit, The WWW Conference or still EuroPython.
Detail behind the Apache Cassandra 2.0 release and what is new in it including Lightweight Transactions (compare and swap) Eager retries, Improved compaction, Triggers (experimental) and more!
• CQL cursors
Tales From The Front: An Architecture For Multi-Data Center Scalable Applicat...DataStax Academy
- Quick review of Cassandra functionality that applies to this use case
- Common Data Center and application architectures for highly available inventory applications, and why the were designed that way
- Cassandra implementations vis-a-vis infrastructure capabilities
The impedance mismatch: compromises made to fit into IT infrastructures designed and implemented with an old mindset
This is a presentation of the popular NoSQL database Apache Cassandra which was created by our team in the context of the module "Business Intelligence and Big Data Analysis".
Apache Cassandra is a highly scalable second-generation distributed database, bringing together Dynamo's fully distributed design and Bigtable's ColumnFamily-based data model.
This presentation, given at FOSDEM in 2010, provides a brief summary of cassandra's history, a high-level overview of the architecture and data model, and showcases some real life use-cases.
What is Apache Cassandra? | Apache Cassandra Tutorial | Apache Cassandra Intr...Edureka!
** Apache Cassandra Certification Training: https://www.edureka.co/cassandra **
This Edureka tutorial on "What is Apache Cassandra" will give you a detailed introduction to the NoSQL database Apache Cassandra and it's various features. Learn why Cassandra is preferred over other Databases. You will also learn about the various elements of Cassandra Database with an interactive Industry based Use Case.
C* Summit 2013: Cassandra at eBay Scale by Feng Qu and Anurag JambhekarDataStax Academy
We have seen rapid adoption of C* at eBay in past two years. We have made tremendous efforts to integrate C* into existing database platforms, including Oracle, MySQL, Postgres, MongoDB, XMP etc.. We also scale C* to meet business requirement and encountered technical challenges you only see at eBay scale, 100TB data on hundreds of nodes. We will share our experience of deployment automation, managing, monitoring, reporting for both Apache Cassandra and DataStax enterprise.
What Every Developer Should Know About Database Scalabilityjbellis
Replication. Partitioning. Relational databases. Bigtable. Dynamo. There is no one-size-fits-all approach to scaling your database, and the CAP theorem proved that there never will be. This talk will explain the advantages and limits of the approaches to scaling traditional relational databases, as well as the tradeoffs made by the designers of newer distributed systems like Cassandra. These slides are from Jonathan Ellis's OSCON 09 talk: http://en.oreilly.com/oscon2009/public/schedule/detail/7955
Cassandra is a highly scalable, eventually consistent, distributed, structured columnfamily store with no single points of failure, initially open-sourced by Facebook and now part of the Apache Incubator. These slides are from Jonathan Ellis's OSCON 09 talk: http://en.oreilly.com/oscon2009/public/schedule/detail/7975
Apache Cassandra operations have the reputation to be simple on single datacenter deployments and / or low volume clusters but they become way more complex on high latency multi-datacenter clusters with high volume and / or high throughout: basic Apache Cassandra operations such as repairs, compactions or hints delivery can have dramatic consequences even on a healthy high latency multi-datacenter cluster.
In this presentation, Julien will go through Apache Cassandra mutli-datacenter concepts first then show multi-datacenter operations essentials in details: bootstrapping new nodes and / or datacenter, repairs strategy, Java GC tuning, OS tuning, Apache Cassandra configuration and monitoring.
Based on his 3 years experience managing a multi-datacenter cluster against Apache Cassandra 2.0, 2.1, 2.2 and 3.0, Julien will give you tips on how to anticipate and prevent / mitigate issues related to basic Apache Cassandra operations with a multi-datacenter cluster.
About the Speaker
Julien Anguenot VP Software Engineering, iland Internet Solutions, Corp
Julien currently serves as iland's Vice President of Software Engineering. Prior to joining iland, Mr. Anguenot held tech leadership positions at several open source content management vendors and tech startups in Europe and in the U.S. Julien is a long time Open Source software advocate, contributor and speaker: Zope, ZODB, Nuxeo contributor, Zope and OpenStack foundations member, his talks includes Apache Con, Cassandra summit, OpenStack summit, The WWW Conference or still EuroPython.
Detail behind the Apache Cassandra 2.0 release and what is new in it including Lightweight Transactions (compare and swap) Eager retries, Improved compaction, Triggers (experimental) and more!
• CQL cursors
Tales From The Front: An Architecture For Multi-Data Center Scalable Applicat...DataStax Academy
- Quick review of Cassandra functionality that applies to this use case
- Common Data Center and application architectures for highly available inventory applications, and why the were designed that way
- Cassandra implementations vis-a-vis infrastructure capabilities
The impedance mismatch: compromises made to fit into IT infrastructures designed and implemented with an old mindset
This is a presentation of the popular NoSQL database Apache Cassandra which was created by our team in the context of the module "Business Intelligence and Big Data Analysis".
Технический семинар для сотрудников компании МаксимаТелеком , проведенная 18.05.2016. В ходе семинара рассматривались следующие ключевые моменты:
1) IoC принцип
2) Beans life cycle
4) AOP
5) Spring proxy
A general- ‐purpose build automation tool. It can automate building, testing, deployment, publishing, generate documentation etc.
Designed to take advantage of convention over configuration.
Combines the power and flexibility of Ant with the dependency management and
conventions of Maven into a more effective way to build.
This presentation mentions about what ORM is, its advantages/disadvantages. Paradigm shift, parts of ORM, Hibernate & JPA relationship, mapping metadata concepts, object query language examples and so on.
Get the Most out of Testing with Spring 4.2Sam Brannen
Join Sam Brannen and Nicolas Fränkel to discover what's new in Spring Framework 4.2's testing support and learn tips and best practices for testing modern, Spring-based applications.
Sam Brannen is the Spring Test component lead and author of the Spring TestContext Framework, and Nicolas Fränkel is the author of the book "Integration Testing from the Trenches".
In this session, Sam and Nicolas will cover the latest testing features in Core Spring, Spring Boot, and Spring Security. In addition to new features, they will also present insider tips and best practices on integration testing with suites in TestNG, database transactions, SQL script execution, granularity of context configuration files, optimum use of the context cache, a discussion on TestNG vs. JUnit, and much more.
"Google Web Toolkit" presents a case-study in GWT v2 development. This is an introductory to intermediate talk that looks at solid practices for developing a rich Web GUI within the context of a Spring v3 backend architecture.
In the talk Bryan will present:
* Introduction to GWT (basic demo app)
* Building View
* Building Presenters
* Talking to the Server
* Extending GWT
* DataGrids in GWT
NoSql vs Sql databases. Before creating any IT solution it is really important to decide which database we are going to use. I have covered very high level topic in my slides.
Виталий Бондаренко "Fast Data Platform for Real-Time Analytics. Architecture ...Fwdays
We will start from understanding how Real-Time Analytics can be implemented on Enterprise Level Infrastructure and will go to details and discover how different cases of business intelligence be used in real-time on streaming data. We will cover different Stream Data Processing Architectures and discus their benefits and disadvantages. I'll show with live demos how to build Fast Data Platform in Azure Cloud using open source projects: Apache Kafka, Apache Cassandra, Mesos. Also I'll show examples and code from real projects.
NoSQL – Data Center Centric Application EnablementDATAVERSITY
The growth of Datacenter infrastructure is trending out of bounds, along with the pace in user activity and data generation in this digital era. However, the nature of the typical application deployment within the data center is changing to accommodate new business needs. Those changes introduce complexities in application deployment architecture and design, which cascade into requirements for a new generation of database technology (NoSQL) destined to ease that complexity. This webcast will discuss the modern data centers data centric application, the complexities that must be dealt with and common architectures found to describe and prescribe new data center aware services. Well look at the practical issues in implementation and overview current state of art in NoSQL database technology solving the problems of data center awareness in application development.
Cassandra from the trenches: migrating Netflix (update)Jason Brown
Update talk on Cassandra at Netflix, presented at the Silicon Valley NoSQL meetup on 9 Feb 2012. Includes an introduction to Astyanax, an open source cassandra client written in java.
NoSQL is not a buzzword anymore. The array of non- relational technologies have found wide-scale adoption even in non-Internet scale focus areas. With the advent of the Cloud...the churn has increased even more yet there is no crystal clear guidance on adoption techniques and architectural choices surrounding the plethora of options available. This session initiates you into the whys & wherefores, architectural patterns, caveats and techniques that will augment your decision making process & boost your perception of architecting scalable, fault-tolerant & distributed solutions.
This is a preliminary study and the objective of this study is to make simple distributed database system with some basic tutorials. Cassandra is a distributed database from Apache that is highly scalable and designed to accomplish very large amounts of organized data. Without having a single point of failure, it offers high accessibility. This report highlights with a basic outline of Cassandra trailed by its architecture, installation, and significant classes and interfaces. Subsequently, it proceeds to cover how to perform operations such as CREATE, ALTER, UPDATE, and DELETE on KEYSPACES, TABLES, and INDEXES using CQLSH using C#/.NET Client with a sample program done by ASP.NET(C#).
Similar to Cassandra for mission critical data (20)
Listen to the keynote address and hear about the latest developments from Rachana Ananthakrishnan and Ian Foster who review the updates to the Globus Platform and Service, and the relevance of Globus to the scientific community as an automation platform to accelerate scientific discovery.
Your Digital Assistant.
Making complex approach simple. Straightforward process saves time. No more waiting to connect with people that matter to you. Safety first is not a cliché - Securely protect information in cloud storage to prevent any third party from accessing data.
Would you rather make your visitors feel burdened by making them wait? Or choose VizMan for a stress-free experience? VizMan is an automated visitor management system that works for any industries not limited to factories, societies, government institutes, and warehouses. A new age contactless way of logging information of visitors, employees, packages, and vehicles. VizMan is a digital logbook so it deters unnecessary use of paper or space since there is no requirement of bundles of registers that is left to collect dust in a corner of a room. Visitor’s essential details, helps in scheduling meetings for visitors and employees, and assists in supervising the attendance of the employees. With VizMan, visitors don’t need to wait for hours in long queues. VizMan handles visitors with the value they deserve because we know time is important to you.
Feasible Features
One Subscription, Four Modules – Admin, Employee, Receptionist, and Gatekeeper ensures confidentiality and prevents data from being manipulated
User Friendly – can be easily used on Android, iOS, and Web Interface
Multiple Accessibility – Log in through any device from any place at any time
One app for all industries – a Visitor Management System that works for any organisation.
Stress-free Sign-up
Visitor is registered and checked-in by the Receptionist
Host gets a notification, where they opt to Approve the meeting
Host notifies the Receptionist of the end of the meeting
Visitor is checked-out by the Receptionist
Host enters notes and remarks of the meeting
Customizable Components
Scheduling Meetings – Host can invite visitors for meetings and also approve, reject and reschedule meetings
Single/Bulk invites – Invitations can be sent individually to a visitor or collectively to many visitors
VIP Visitors – Additional security of data for VIP visitors to avoid misuse of information
Courier Management – Keeps a check on deliveries like commodities being delivered in and out of establishments
Alerts & Notifications – Get notified on SMS, email, and application
Parking Management – Manage availability of parking space
Individual log-in – Every user has their own log-in id
Visitor/Meeting Analytics – Evaluate notes and remarks of the meeting stored in the system
Visitor Management System is a secure and user friendly database manager that records, filters, tracks the visitors to your organization.
"Secure Your Premises with VizMan (VMS) – Get It Now"
Exploring Innovations in Data Repository Solutions - Insights from the U.S. G...Globus
The U.S. Geological Survey (USGS) has made substantial investments in meeting evolving scientific, technical, and policy driven demands on storing, managing, and delivering data. As these demands continue to grow in complexity and scale, the USGS must continue to explore innovative solutions to improve its management, curation, sharing, delivering, and preservation approaches for large-scale research data. Supporting these needs, the USGS has partnered with the University of Chicago-Globus to research and develop advanced repository components and workflows leveraging its current investment in Globus. The primary outcome of this partnership includes the development of a prototype enterprise repository, driven by USGS Data Release requirements, through exploration and implementation of the entire suite of the Globus platform offerings, including Globus Flow, Globus Auth, Globus Transfer, and Globus Search. This presentation will provide insights into this research partnership, introduce the unique requirements and challenges being addressed and provide relevant project progress.
A Comprehensive Look at Generative AI in Retail App Testing.pdfkalichargn70th171
Traditional software testing methods are being challenged in retail, where customer expectations and technological advancements continually shape the landscape. Enter generative AI—a transformative subset of artificial intelligence technologies poised to revolutionize software testing.
Advanced Flow Concepts Every Developer Should KnowPeter Caitens
Tim Combridge from Sensible Giraffe and Salesforce Ben presents some important tips that all developers should know when dealing with Flows in Salesforce.
Climate Science Flows: Enabling Petabyte-Scale Climate Analysis with the Eart...Globus
The Earth System Grid Federation (ESGF) is a global network of data servers that archives and distributes the planet’s largest collection of Earth system model output for thousands of climate and environmental scientists worldwide. Many of these petabyte-scale data archives are located in proximity to large high-performance computing (HPC) or cloud computing resources, but the primary workflow for data users consists of transferring data, and applying computations on a different system. As a part of the ESGF 2.0 US project (funded by the United States Department of Energy Office of Science), we developed pre-defined data workflows, which can be run on-demand, capable of applying many data reduction and data analysis to the large ESGF data archives, transferring only the resultant analysis (ex. visualizations, smaller data files). In this talk, we will showcase a few of these workflows, highlighting how Globus Flows can be used for petabyte-scale climate analysis.
TROUBLESHOOTING 9 TYPES OF OUTOFMEMORYERRORTier1 app
Even though at surface level ‘java.lang.OutOfMemoryError’ appears as one single error; underlyingly there are 9 types of OutOfMemoryError. Each type of OutOfMemoryError has different causes, diagnosis approaches and solutions. This session equips you with the knowledge, tools, and techniques needed to troubleshoot and conquer OutOfMemoryError in all its forms, ensuring smoother, more efficient Java applications.
Quarkus Hidden and Forbidden ExtensionsMax Andersen
Quarkus has a vast extension ecosystem and is known for its subsonic and subatomic feature set. Some of these features are not as well known, and some extensions are less talked about, but that does not make them less interesting - quite the opposite.
Come join this talk to see some tips and tricks for using Quarkus and some of the lesser known features, extensions and development techniques.
Strategies for Successful Data Migration Tools.pptxvarshanayak241
Data migration is a complex but essential task for organizations aiming to modernize their IT infrastructure and leverage new technologies. By understanding common challenges and implementing these strategies, businesses can achieve a successful migration with minimal disruption. Data Migration Tool like Ask On Data play a pivotal role in this journey, offering features that streamline the process, ensure data integrity, and maintain security. With the right approach and tools, organizations can turn the challenge of data migration into an opportunity for growth and innovation.
Innovating Inference - Remote Triggering of Large Language Models on HPC Clus...Globus
Large Language Models (LLMs) are currently the center of attention in the tech world, particularly for their potential to advance research. In this presentation, we'll explore a straightforward and effective method for quickly initiating inference runs on supercomputers using the vLLM tool with Globus Compute, specifically on the Polaris system at ALCF. We'll begin by briefly discussing the popularity and applications of LLMs in various fields. Following this, we will introduce the vLLM tool, and explain how it integrates with Globus Compute to efficiently manage LLM operations on Polaris. Attendees will learn the practical aspects of setting up and remotely triggering LLMs from local machines, focusing on ease of use and efficiency. This talk is ideal for researchers and practitioners looking to leverage the power of LLMs in their work, offering a clear guide to harnessing supercomputing resources for quick and effective LLM inference.
Into the Box Keynote Day 2: Unveiling amazing updates and announcements for modern CFML developers! Get ready for exciting releases and updates on Ortus tools and products. Stay tuned for cutting-edge innovations designed to boost your productivity.
OpenFOAM solver for Helmholtz equation, helmholtzFoam / helmholtzBubbleFoamtakuyayamamoto1800
In this slide, we show the simulation example and the way to compile this solver.
In this solver, the Helmholtz equation can be solved by helmholtzFoam. Also, the Helmholtz equation with uniformly dispersed bubbles can be simulated by helmholtzBubbleFoam.
Designing for Privacy in Amazon Web ServicesKrzysztofKkol1
Data privacy is one of the most critical issues that businesses face. This presentation shares insights on the principles and best practices for ensuring the resilience and security of your workload.
Drawing on a real-life project from the HR industry, the various challenges will be demonstrated: data protection, self-healing, business continuity, security, and transparency of data processing. This systematized approach allowed to create a secure AWS cloud infrastructure that not only met strict compliance rules but also exceeded the client's expectations.
Cyaniclab : Software Development Agency Portfolio.pdfCyanic lab
CyanicLab, an offshore custom software development company based in Sweden,India, Finland, is your go-to partner for startup development and innovative web design solutions. Our expert team specializes in crafting cutting-edge software tailored to meet the unique needs of startups and established enterprises alike. From conceptualization to execution, we offer comprehensive services including web and mobile app development, UI/UX design, and ongoing software maintenance. Ready to elevate your business? Contact CyanicLab today and let us propel your vision to success with our top-notch IT solutions.
Paketo Buildpacks : la meilleure façon de construire des images OCI? DevopsDa...Anthony Dahanne
Les Buildpacks existent depuis plus de 10 ans ! D’abord, ils étaient utilisés pour détecter et construire une application avant de la déployer sur certains PaaS. Ensuite, nous avons pu créer des images Docker (OCI) avec leur dernière génération, les Cloud Native Buildpacks (CNCF en incubation). Sont-ils une bonne alternative au Dockerfile ? Que sont les buildpacks Paketo ? Quelles communautés les soutiennent et comment ?
Venez le découvrir lors de cette session ignite
Understanding Globus Data Transfers with NetSageGlobus
NetSage is an open privacy-aware network measurement, analysis, and visualization service designed to help end-users visualize and reason about large data transfers. NetSage traditionally has used a combination of passive measurements, including SNMP and flow data, as well as active measurements, mainly perfSONAR, to provide longitudinal network performance data visualization. It has been deployed by dozens of networks world wide, and is supported domestically by the Engagement and Performance Operations Center (EPOC), NSF #2328479. We have recently expanded the NetSage data sources to include logs for Globus data transfers, following the same privacy-preserving approach as for Flow data. Using the logs for the Texas Advanced Computing Center (TACC) as an example, this talk will walk through several different example use cases that NetSage can answer, including: Who is using Globus to share data with my institution, and what kind of performance are they able to achieve? How many transfers has Globus supported for us? Which sites are we sharing the most data with, and how is that changing over time? How is my site using Globus to move data internally, and what kind of performance do we see for those transfers? What percentage of data transfers at my institution used Globus, and how did the overall data transfer performance compare to the Globus users?
2. Agenda
1) CAP Theorem
2) NoSQL vs RDBMS: advantages and disadvantages
3) What is Cassandra? History.
4) Cassandra features
5) Cassandra datamodel
6) Ways to access data: Thrift, CQL, Kundera ORM
3. What is NoSQL
NoSQL Not SQL
does not mean
NoSQL Not Only SQL
OR
Not Relational Database
it means
4. CAP Theorem
You can choose only two: Consistency, Availability, Partition tolerance
7. RDBMS
+ Strong mathematical basis
+ Referential Integrity
+ ACID transactions
+ Standard SQL
+ Well-known approaches to data modeling
- Poor performance at great data amounts
- Scaling issues
8. NoSQL
+ Great performance
+ Flexible data schema
+ Easy scaling
- Data redundancy
- Integrity should be ensured by developer in most
cases
- Different access interfaces for different stores
- Paradigm shift required
- BASE consistency model instead of ACID
transactions
9. ACID consistency model
Atomicity
• Transactions
are all or
nothing
Consistency
• Data written is
valid according
all rules:
Isolation
• Transactions
do not affect
each other
Durability
• Data written
will not be lost
16. Cassandra Features
Decentralized
• each node has the
same role and can
process any
request
Replication
• Cassandra
supports
multi -
datacenter
replication
Scalable
• read and
write
throughput
both increase
linearly as
new
machines are
added
Durable
• data write
once will
survive in
case of
hardware
failure
23. Write path in Cassandra
• Data is written to any node called coordinator
• Data is written to commitlog(for durability) and then to memTable
• MemTable is flushed to disk(SSTable) periodically, it is recreated in memory
• Deletes are special cases of writes - tombstones
24. Read path in Cassandra
• Any server can be queried, it acts as coordinator
• Contacts node with requested key
• If consistency < ALL, read repair is performed on background
Read at consistency level = ONE
25. Read repair
• Read repair means that when a query is made against a given key, we
perform a digest query against all the replicas of the key and push
the most recent version to any out-of-date replicas.
31. Indexes
• Primary index – index built by key of the each row
• Secondary index – index on column values,
should be created manually. Good only for low
cardinality columns.
Example: columns Gender can have only two values:
M and F.
And it is a problem.
• Indexing is performed in background
32. Data modelling
• Query-driven approach is
required
• How to get data if I can
query only by key?
• Denormalize it!
• Create multiple tables for
data
• Use fast writes to do few
reads as possible
33. What Cassandra is good for?
Time series data
(logs, sensor data)
Write
intensive
applications
Applications
with
predefined
query-model
34. Never use Cassandra
• If you want to replace traditional RDBMS with it.
• If you can’t tell in which way your data will be queried
• If you have a lot of reads
• If strong consistency is required (financial, medical areas)
• Cassandra is not a silver-bullet solution
35.
36. Ways to access data
Thrift
• First & native
client.
Deprecated.
Hector, Pelops
• Libraries based
on Thrift
CQL
• SQL-like
language,
very limited
Kundera
• ORM/ONM
framework
37. Thrift
• Apache Thrift – framework for cross-language
services development
• Supported languages: C++, Java, Python, PHP,
Ruby, Erlang, Perl, Haskell, C#, Cocoa, JavaScript,
Smalltalk, OCaml and others.
• Was developed by Facebook and released in 2007
• Deprecated
38. Hector
• Hector - is a high level Java client for Apache
Cassandra currently in use on a number of
production systems.
• Includes an incredible number of features
39. Hector main features
• Security – connection using Kerberos
• Speed4j monitoring library integrating capabilities
• Hector Object Mapper – simple ORM(not
compliant with JPA )
• Connection pooling
• Failover behavior on client side
40. CQL
CQL – a SQL-like language introduced in Cassandra
0.8
Offers next functionality:
• No JOINS
• Creating/dropping keyspaces, column families,
columns and rows
• Inserting/retrieving columns
• Indexing
41. Kundera ORM
Kundera is a “Polyglot Object Mapper”
Supports:
◦ Cassandra
◦ HBase
◦ MongoDB
◦ RDBMS
◦ and other
46. Performance Comparison
Concurrent + Bulk load – 1000 record per thread
Number Of Threads
(1000 rec/ thread)
Pelops Time (in sec) Hector Time (in sec) Kundera (in sec)
10 5.929 5.286 7.722
100 34.750 32.228 39.124
1000 368.022 352.711 393.931
48. Cassandra limitations
The key
(and
column
names)
must < 64K
bytes.
The
maximum
number of
column per
row is 2
billion.
A single
column
value may
not be
larger than
2GB.
All data
read should
fit in
memory
due to
Thrift
streaming
support lack
49. Summary
Great I/O performance
Several data access interfaces
AP data store (CAP)
Production ready & production proved
Good for time series data
Extremely available
Consistency
All the servers in the system will have the same data so anyone using the system will get the same copy regardless of which server answers their request.
Availability
The system will always respond to a request (even if it's not the latest data or consistent across the system or just a message saying the system isn't working)
Partition Tolerance
The system continues to operate as a whole even if individual servers fail or can't be reached..
Cassandra was developed by Facebook by one of the authors of Amazon DynamoDB to solve the problem of inbox search
In 2008 Cassandra was released as an OpenSource project on Google Code
In 2010 Cassandra became a top-level Apache project
