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Migrating from MongoDB to Cassandra

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Re: Migrating from MongoDB to Cassandra

#11

Post by jb007 »

DigitalSea wrote: post #3

When I read posts like this all but confirming MongoDB isn't the great product 10Gen make it out to be, I wonder how the heck MongoDB are still even relevant and then I remind myself of the fact that 10Gen have one of the best marketing and sales teams in the game at the moment. While MongoDB has improved greatly over previous versions, I can't help but feel if 10Gen put as much effort into improving their product as…

Mongodb has marketed the database as a general purpose one when in reality it doesn't even come close to one. And the case is the same for all other NoSQL systems. No More general purpose database? The developers at http://www.amisalabs.com are tackling today's database problems.

Re: Migrating from MongoDB to Cassandra

#12

Post by leif »

rogerbinns wrote: post #9
DigitalSea wrote: post #3

When I read posts like this all but confirming MongoDB isn't the great product 10Gen make it out to be, I wonder how the heck MongoDB are still even relevant and then I remind myself of the fact that 10Gen have one of the best marketing and sales teams in the game at the moment. While MongoDB has improved greatly over previous versions, I can't help but feel if 10Gen put as much effort into improving their product as…

There is one thing MongoDB does spectacularly well - you can feed in arbitrary JSON and get the same JSON back out. (No need to define schemas or play any kind of system/db administrator.) Even the queries have the same "shape" as JSON, so no need for another arbitrary query language. It will eventually bite you, and bite you hard. But you'll be well into the millions of records before that happens. Developers and pr…

It's telling that those jira tickets are both in the top five most voted on open server tickets and are from 2010 and before. (I know you know this roger, but) TokuMX completely resolves both of them.

Re: Migrating from MongoDB to Cassandra

#13

Post by CptCodeMonkey »

DigitalSea wrote: post #3

When I read posts like this all but confirming MongoDB isn't the great product 10Gen make it out to be, I wonder how the heck MongoDB are still even relevant and then I remind myself of the fact that 10Gen have one of the best marketing and sales teams in the game at the moment. While MongoDB has improved greatly over previous versions, I can't help but feel if 10Gen put as much effort into improving their product as…

Knowing some of the FC people first hand, MongoDB did actually serve them fairly well for a substantial amount of time. Until they started hitting max limits, it didn't really make sense to move to c.

Going straight to C or something like it would have been almost cargo-cultish ( eg If we build industrial strength, we will get industrial levels of traffic ).

Re: Migrating from MongoDB to Cassandra

#14

Post by rogerbinns »

leif wrote: post #12
rogerbinns wrote: post #9

Earlier quoted context omitted.

There is one thing MongoDB does spectacularly well - you can feed in arbitrary JSON and get the same JSON back out. (No need to define schemas or play any kind of system/db administrator.) Even the queries have the same "shape" as JSON, so no need for another arbitrary query language. It will eventually bite you, and bite you hard. But you'll be well into the millions of records before that happens. Developers and pr…

It's telling that those jira tickets are both in the top five most voted on open server tickets and are from 2010 and before. (I know you know this roger, but) TokuMX completely resolves both of them.

But does TokuMX solve all the other issues like write concurrency, eye wateringly slow (and single threaded) index building, or there being no way to practically reduce the file sizes. (repairDB takes forever and requires the same amount of free space as already used, and compact also needs free space and doesn't remove any files).

Re: Migrating from MongoDB to Cassandra

#15

Post by [deleted] »

Xorlev wrote: post #6
brightsize wrote: post #5

Earlier quoted context omitted.

Same here.

Author here, sorry about that. It's not supposed to display on engineering posts but something must have changed/been broken recently. We know you guys aren't interested in marketing content. Again, sorry about that and thanks for bringing it up.

[deleted]

Re: Migrating from MongoDB to Cassandra

#16

Post by zardosht »

rogerbinns wrote: post #14
leif wrote: post #12

Earlier quoted context omitted.

It's telling that those jira tickets are both in the top five most voted on open server tickets and are from 2010 and before. (I know you know this roger, but) TokuMX completely resolves both of them.

But does TokuMX solve all the other issues like write concurrency, eye wateringly slow (and single threaded) index building, or there being no way to practically reduce the file sizes. (repairDB takes forever and requires the same amount of free space as already used, and compact also needs free space and doesn't remove any files).

(I work for Tokutek)

Write concurrecy: yes, TokuMX does not have a database level reader/writer lock.

Index Building: yes, fractal trees can write data much more efficiently, so if index building is a problem, I bet TokuMX solves it.

Practically reducing file size: to be honest, I am not sure because due to our great compression, this has not been a general issue for our users. Our reindex command could reduce file size, but I cannot point to examples.

One of our big goals is to address storage issues MongoDB has.

Re: Migrating from MongoDB to Cassandra

#18

Post by threeseed »

chaostheory wrote: post #4
DigitalSea wrote: post #3

When I read posts like this all but confirming MongoDB isn't the great product 10Gen make it out to be, I wonder how the heck MongoDB are still even relevant and then I remind myself of the fact that 10Gen have one of the best marketing and sales teams in the game at the moment. While MongoDB has improved greatly over previous versions, I can't help but feel if 10Gen put as much effort into improving their product as…

Like any other NoSQL datastore, things like MongoDB aren't as general purpose as a RDBMS no matter how the marketing and sales teams make them out to be. Cassandra is no different. People need to read the documentation (say what you will about mongo but 10Gen docs are pretty damn good) more thoroughly before blindly implementing stuff on NoSQL and complaining. (I've been guilty of this in the past.)

For me anyone that uses the term "NoSQL" to group completely different databases simply doesn't understand what they are talking about.

Cassandra and MongoDB are completely fine as general purpose databases. With CQL3 Cassandra is just as easy to use as any RDBMS with the advantage of being infinitely more scalable and easier to manage.

Re: Migrating from MongoDB to Cassandra

#19

Post by threeseed »

CptCodeMonkey wrote: post #13
DigitalSea wrote: post #3

When I read posts like this all but confirming MongoDB isn't the great product 10Gen make it out to be, I wonder how the heck MongoDB are still even relevant and then I remind myself of the fact that 10Gen have one of the best marketing and sales teams in the game at the moment. While MongoDB has improved greatly over previous versions, I can't help but feel if 10Gen put as much effort into improving their product as…

Knowing some of the FC people first hand, MongoDB did actually serve them fairly well for a substantial amount of time. Until they started hitting max limits, it didn't really make sense to move to c . Going straight to C or something like it would have been almost cargo-cultish ( eg If we build industrial strength, we will get industrial levels of traffic ).

Exactly. Can you imagine all of the Java/C developers telling Ruby developers that they are idiots and don't know anything about programming ? Simply because they choose a technology that is designed for developer productivity at the expense of scalability.

Because that what seems to happen for every database discussion.

Re: Migrating from MongoDB to Cassandra

#20

Post by Xorlev »

fiatmoney wrote: post #17

Sounds the intended use case for ElasticSearch. "Given some input piece of data {email, phone, Twitter, Facebook}, find other data related to that query and produce a merged document of that data"

I will say ElasticSearch features heavily in our infrastructure elsewhere, but for the Person API product, it's purely a primary-key lookup.

My coworker wrote a bit about how the search functionality of our offering works here: http://www.fullcontact.com/blog/sherlock_search_engine_that_...

That might make more sense why we do PK lookups.

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