Transcript The Trouble with NoSQL Databases

Iran Hutchinson
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I work for InterSystems who drives the new
http://globalsdb.org NoSQL project.
Email: [email protected]
Twitter: #iranic
Skype: chatwithiran
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… NoSQL Databases
 Understanding what they are
 Understanding how to leverage their strengths
 Understanding their weaknesses
 Staying away from hype and religious wars
 Fighting your developer demon
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Edgar Frank “Ted” Codd
Known for 12 Rules (0 ~ 12) for Relational Data
Systems
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Rule 1: The information Rule
 All information is represented in 1 and only 1 way,
namely by values in column positions within rows
of tables
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Rule 12: The no subversion Rule
 If the system provides a low-level (record-at-a-
time) interface, then that interface cannot be
used to subvert the system i.e. relational security
or integrity constraints.
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Simple APIs
 Java Example: Document.save(myObject)
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Seamless language integration
 No impedance mismatch
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Designed to be horizontally scalable (elastic)
Flexible data model
Majority free and/or Open Source
Free and Commercial production support
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Proven
Available talent / Well-known
AD-Hoc querying
Scalable (limits?)
Free and Commercial production support
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Interface for data access
Limited horizontal scalability?
Impedance mismatches
Programming model
In-flexible data model
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Does not include the underlying data
structure.
B-tree and B+-trees can be fast and efficient
The relational model + SQL can limit B-trees
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Class of data management systems
inherently
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Non-relational
Distributed
Horizontally scalable
With optional schemas
Providing simple APIs
Term Not-Only-SQL recently embraced
Dave Kellog’s Blog Post
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No to ACID
No to the impedance mismatch with SQL
Dealing with Big Data and Web Scale
High prices from RDBMS vendors
Use commodity hardware
Flexible data models
It’s a cool movement ….
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No
Remember MUMPS?
 SET ^Car("Door","Color")="BLUE”
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Remember Multi-value/PICK
 MATWRITE array.variable ON file.variable,id. ….
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Ever heard of the NoSQL RDB?
Key-Value
Graph
Data
Column
Document
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This depends on your use case.
Example
 http://www.mongodb.org/display/DOCS/Use+Cas
es
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Compare your problems to others.
Example:
 http://wiki.apache.org/hadoop/PoweredBy
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http://nosql-database.org/ lists 122 today.
Depends on your model selection.
Most likely choose well-known project.
Don’t forget about shared risk!
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Some solutions have no querying
When available query languages differ
Lack of general AD-Hoc querying – “no” SQL
NOTE: Toad for Cloud
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Skills
Data Model
Data format
Tools
Standards?
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Some databases are not as proven
Incomplete NoSQL solutions
 You write a larger data management tier
 You maintain your business code and
infrastructure code
 You have to customize management and
deployment technology and procedures
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Know your application
Don’t forget the past lessons
Consider a hybrid approach
Fight the desire to Roll-Your-Own-DB
Start small but significant
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Two Systems
 NoSQL + SQL/RDBMS
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Updates
 Real-time
 Asynchronous or Batch
NoSQL
Data
Mapper /
Translato
r
SQL/RDB
MS
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One system does
both NoSQL and
SQL
Relational
?
Key-Value
Data
Graph
Document
Column
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InterSystems Caché supports SQL and NoSQL
Production NoSQL for 20+ years
APIs for .NET, Java, Perl, Python, etc.
Expanding paradigms for more use cases.
Comes the closest to approach 2
Relational
?
Key-Value
Data
Graph
Document
Column
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Core of InterSystems Caché
Free for development and production
Simple APIs Java and JavaScript
http://globalsdb.org
Sponsored by InterSystems
Array
Data
?
Document
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Over time I think we will see
 NoSQL features in mainstream databases
 NoSQL offerings by more commercial companies
 Dominant open source / free NoSQL projects
 New definitions of enterprise databases
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Hadoop/Hbase
Cassandra
MongoDB
CouchDB
Riak
Couchbase
Neo4J
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InterSystems Caché
SimpleDB
Azure Table Storage
Google App Engine Data Storage
Mark Logic Server
Infinite Graph
Riak (has open source version)
Berkely DB