Comments on: Load balancing and improved failover in Hector

By: Hector API v2 | PrettyPrint.me

Hector API v2 | PrettyPrint.me — Fri, 06 Aug 2010 11:34:35 +0000

[...] simple load balancing [...]

By: OCTO talks ! » Let’s play with Cassandra… (Part 1/3)

OCTO talks ! » Let’s play with Cassandra… (Part 1/3) — Wed, 09 Jun 2010 20:18:05 +0000

[...] library (for instance Hector in the Java World) provides connections pooling mechanisms and even kind of round-robin load [...]

By: OCTO talks ! » Jouons avec Cassandra… (1/3)

OCTO talks ! » Jouons avec Cassandra… (1/3) — Wed, 09 Jun 2010 20:16:17 +0000

[...] librairies (par exemple Hector dans le monde Java) fournissent des mécanismes de pool de connections et même de [...]

By: Ran Tavory

Ran Tavory — Tue, 04 May 2010 09:55:24 +0000

@Falk this cannot be done out of the box. I’ll give you my answer, but really this is a question suitable to user@cassandra.

you can do this by implementing an application level index
Or by denormalizing the data
Or wait until cassandra adds indexes (I think version 0.7.0, but not sure)

By: Falk Wolsky

Falk Wolsky — Mon, 03 May 2010 17:08:04 +0000

Hello Ran,

hmm. the answer on this List was “not so good”…
I Think, Lucandra can be a good point to start indexing and Text-Search. I have to evaluate this..

Ok. Please let us focus to the relation question:
(Sample Data-Model from Arin)

BlogEntries : {
i-got-a-new-guitar : { // row key
title: This is a blog entry about my new, awesome guitar,
body: this is a cool entry. etc etc yada yada
author: Arin Sarkissian // a row key into the Authors CF
}
}

Now, the question is: See you any possibility to build a “get” Function with it i can find all “BlogEntries” from a “named” autor?

For sample:
ks.getColumn(search,key,ColumnPath); (simplified)
“search” should be {column:value} / {author:Arin Sarkissian} and key for this sample can be used or not set (“*”).

Maybe we can handle this inside a SliceRange “query”?

Thanks in Advance

By: Ran Tavory

Ran Tavory — Sun, 02 May 2010 09:33:00 +0000

Hi @Falk, this is an excellent question to user@cassandra

By: Falk Wolsky

Falk Wolsky — Sun, 02 May 2010 09:13:49 +0000

Hello Ran,

1) Can you provide a solution or a sample for searching (Column and SuperColumn) (Fulltext). What is the Way to realize this? Hadoop/MapReduce? See you a posibility to build/use a index for columns?

2) How can be realized a “relation” For Sample: (http://arin.me/blog/wtf-is-a-supercolumn-cassandra-data-model) Arin describes good a simple Data-Model to build a Blog. But how can we read (filter) all Posts from “BlogEntries” from a single Autor? (filter the Supercolumns by a culum inside of a SuperColumn)

The “relation” for Sample is Autor -> BlogEntries…

To filter the Datas there is a needing to specify in a “get” a Key OR a Column/Value combination…

Thanks in Advance! – and thx for Hector! We love it…
With Hector i build a (Apache)Cocoon-Transformer.

With kind regards,
Falk

By: tc

tc — Sun, 18 Apr 2010 11:17:58 +0000

you got it. Done.

By: Ran Tavory

Ran Tavory — Sun, 18 Apr 2010 07:34:28 +0000

@hc let me look into that, but in the mean time, do you mind taking the discussion to hector-users@googlegroups.com for the benefit of all?

By: tc

tc — Sat, 17 Apr 2010 20:29:33 +0000

thanx Ran .. The problem is, even though I can browse the src on your website to find CassandraHostConfigurator, it is missing in the download for 0.6.0-10. Also the CassandraClientPoolFactory only has a createNew() method instead of a createNew(CassandraHostConfigurator config).

I guess the modification wasn’t made at the time of building the jar for download. Could you please update the download?