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214
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6answers
108483 views

MongoDB vs. Cassandra

I am evaluating what might be the best migration option. Currently, I am on a sharded MySQL (horizontal partition), with most of my data stored in JSON blobs. I do not have any complex SQL q
157
vote
12answers
12519 views

What scalability problems have you encountered using a NoSQL data store?

NoSQL refers to non-relational data stores that break with the history of relational databases and ACID guarantees. Popular open source NoSQL data stores include:
127
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7answers
25744 views

NoSQL (MongoDB) vs Lucene (or Solr) as your database

With the NoSQL movement growing based on document-based databases, I've looked at MongoDB lately. I have noticed a striking similarity with how to treat items as "Documents", just like Lucene does
101
vote
5answers
12646 views

Non-Relational Database Design

I'm interested in hearing about design strategies you have used with non-relational "nosql" databases - that is, the (mostly new) class of data stores that don't use traditional re
101
vote
5answers
23590 views

Ways to implement data versioning in MongoDB

Can you share your thoughts how would you implement data versioning in MongoDB. (I've asked simil
73
vote
3answers
41339 views

Facebook Architecture

I have been scrounging for articles/info about the architecture at Facebook, the challenges & ways they tackle them. What they use & why they use. How do they scale & what are the desig
58
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7answers
20104 views

What's The Best Practice In Designing A Cassandra Data Model?

And what are the pitfalls to avoid? Are there any deal breaks for you? E.g., I've heard that exporting/importing the Cassandra data is very difficult, making me wonder if that's going to hinder syn
58
vote
8answers
23942 views

What should I choose: MongoDB/Cassandra/Redis/CouchDB?

We're developing a really big project and I was wondering if anyone can give me some advice about what DB backend should we pick. Our system is compound by 1100 electronic devices that send
56
vote
3answers
25602 views

Large scale data processing Hbase vs Cassandra

I am nearly landed at Cassandra after my research on large scale data storage solutions. But its generally said that Hbase is better solution for large scale data processing and analysis. W
55
vote
3answers
1550 views

Cassandra server throws java.lang.AssertionError: DecoratedKey(...) != DecoratedKey

I'm currently experimenting around with Cassandra. On the client-side (with Hector) I look up a few keys like this: ColumnFamilyResult<String, String> result = template
53
vote
7answers
2596 views

Life without JOINs... understanding, and common practices

Lots of "BAW"s (big ass-websites) are using data storage and retrieval techniques that rely on huge tables with indexes, and using queries that won't/can't use JOINs in their queries (BigTable, HQL
52
vote
15answers
12739 views

Which key value store is the most promising/stable?

I'm looking to start using a key/value store for some side projects (mostly as a learning experience), but so many have popped up in the recent past that I've got no idea where to begin. Just listi
48
vote
3answers
19747 views

What is the difference between Cassandra and CouchDB?

I'm looking at both projects and I can't really see the difference from Cassandra Site: Cassandra is a highly scalable, eventually consistent, distributed, structured k
48
vote
8answers
13081 views

Best data store for billions of rows

I need to be able to store small bits of data (approximately 50-75 bytes) for billions of records (~3 billion/month for a year). The only requirement is fast inserts and fast lookups for all
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vote
3answers
22972 views

Switching from MySQL to Cassandra - Pros/Cons?

For a bit of background - this question deals with a project running on a single small EC2 instance, and is about to migrate to a medium one. The main components are Django, MySQL and a large numbe
40
vote
8answers
14451 views

When NOT to use Cassandra?

There has been a lot of talk related to Cassandra lately. Twitter, Digg, Facebook, etc all use it. When does it make sense to:
40
vote
2answers
5795 views

What does "Document-oriented" vs. Key-Value mean when talking about MongoDB vs Cassandra?

What does going with a document based NoSQL option buy you over a KV store, and vice-versa?
37
vote
5answers
7280 views

Why are document stores like Lucene / Solr not included in NoSQL conversations?

All of us have come across the recent hype of no-SQL solutions lately. MongoDB, CouchDB, BigTable, Cassandra, and others have been listed as no-SQL options. Here's an example:
36
vote
1answers
8233 views

Explain Merkle Trees for use in Eventual Consistency

Merkle Trees are used as an anti-entropy mechanism in several distributed, replicated key/value stores:
32
vote
1answers
8349 views

Difference between Document-based and Key/Value-based databases?

I know there are three different, popular types of non-sql databases. Key/Value: Redis, Tokyo Cabinet, Memcached ColumnFamily: Cassandra, HBase Document: MongoDB, Cou
31
vote
1answers
26553 views

How to choose between Cassandra, Membase, Hadoop, MongoDB, RDBMS etc.?

Is there a paper/blog-post on when to use Cassandra or Membase or Hadoop or plain old relational databases ? Is there a paper discussing the strengths/weaknesses of each, and on what scenarios eith
30
vote
5answers
12609 views

Is Cassandra production ready for Ruby on Rails?

I'm working on a project that is considering using Cassandra as a database. We would like to eventually migrate to Cassandra even if we use MySQL to start with, given its scalability. I know that b
30
vote
2answers
13011 views

Redis, CouchDB or Cassandra?

What are the strengths and weaknesses of the various NoSQL databases available? In particular, it seems like Redis is weak when it comes to distributing write load over multiple servers. Is
28
vote
5answers
9861 views

storing massive ordered time series data in bigtable derivatives

I am trying to figure out exactly what these new fangled data stores such as bigtable, hbase and cassandra really are. I work with massive amounts of stock market data, billions of rows of p
28
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5answers
11697 views

How to use Cassandra in Django framework

Is there any robust way of implementing Cassandra back end to a web application developed using Django web framework. Thanks
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4answers
9863 views

Cassandra Client Java API's

I have recently started working with Cassandra Database. Now I am in the process of evaluating which Cassandra client we should go forward with. I have seen various post on sta
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6answers
15758 views

Row count of a column family in Cassandra

Is there a way to get a row count (key count) of a single column family in Cassandra? get_count can only be used to get the column count. For instance, if I have a column family containing u
26
vote
2answers
8195 views

How does Voldemort compare to Cassandra?

How does Voldemort compare to Cassandra? I'm not talking about size of community and only wan
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4answers
15615 views

Cassandra port usage - how are the ports used?

When experimenting with Cassandra I've observed that Cassandra listens to the following ports: TCP *:8080 TCP *:8888 TCP *:57311 TCP *:57312 TCP 127
25
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9answers
21578 views

MongoDB vs. Redis vs. Cassandra for a fast-write, temporary row storage solution

I'm building a system that tracks and verifies ad impressions and clicks. This means that there are a lot of insert commands (about 90/second average, peaking at 250) and some read operations, but
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5answers
13669 views

What is an SSTable?

In BigTable/GFS and Cassandra terminology, what is the definition of a SSTable?
24
vote
4answers
18266 views

PHP-friendly NoSQL solutions

I'm looking to use a NoSQL solution for my next project, which will be written in PHP. What choices do I have in terms of NoSQL solutions that can easily interfaced via PHP? I haven't done much thi
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vote
5answers
7829 views

MySQL and NoSQL: Help me to choose the right one

There is a big database, 1,000,000,000 rows, called threads (these threads actually exist, I'm not making things harder just because of I enjoy it). Threads has only a few stuff in it, to make thin
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3answers
8047 views

Sorted String Table (SSTable) or B+ Tree for a Database Index?

Using two databases to illustrate this example: CouchDB and Cassandra. CouchDB C
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2answers
16569 views

bigtable vs cassandra vs simpledb vs dynamo vs couchdb vs hypertable vs riak vs hbase, what do they have in common?

Sorry if this question is somewhat subjective. I am new to 'could store', 'distributed store' or some concepts like this. I really wonder what do they have in common and want to get an overview on
22
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2answers
3946 views

What are the best uses of document stores?

I have been hearing a lot about document oriented data stores like CouchDB. I understand the uses of BigTable like stores such as Cassandra. After reading
21
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4answers
6025 views

Scala + Akka: How to develop a Multi-Machine Highly Available Cluster

We're developing a server system in Scala + Akka for a game that will serve clients in Android, iPhone, and Second Life. There are parts of this server that need to be highly available, running on
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1answers
3296 views

Why Does the Leap Second Cause Problems?

So at this moment (but most likely not for long) Reddit, Meetup, Fark, LinkedIn, Yelp, 4Chan are all down. Netflix apparently was out for a while too. According to Reddit's tweet, they are h
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5answers
8054 views

File Storage for Web Applications: Filesystem vs DB vs NoSQL engines

I have a web application that stores a lot of user generated files. Currently these are all stored on the server filesystem, which has several downsides for me. When we move "folders"
19
vote
4answers
17194 views

MongoDB vs. Cassandra vs. MySQL for real-time advertising platform

I'm working on a real-time advertising platform with a heavy emphasis on performance. I've always developed with MySQL, but I'm open to trying something new like MongoDB or Cassandra if significant