Finding the intersection results of column sets of two rows

Hi all, I want to procure the intersection of columns set of two rows (from 2 different column families). To achieve the intersection results, Can I, first retrieve all columns(around 300) from first row and just query by those column names in the second row(which contains maximum 100 000 columns

Re: Do supercolumns have a purpose?

"My main point was to say that it's think it is better to create tickets for what you want, rather than for something else completely different that would, as a by-product, give you what you want." Then let me say what I want: I want supercolumn families to have any feature that regular column fam

Re: Finding the intersection results of column sets of two rows

Hello, If the amount of data is _that_ small, you'll have a much easier life with MySQL, which supports the "join" procedure -- because that's exactly what you want to achieve. asil klin wrote: > > Hi all, > > I want to procure the intersection of columns set of two rows (from 2 > different c

Re: Finding the intersection results of column sets of two rows

On Sun, Feb 6, 2011 at 10:15 AM, buddhasystem wrote: > > Hello, > > If the amount of data is _that_ small, you'll have a much easier life with > MySQL, which supports the "join" procedure -- because that's exactly what > you want to achieve. > > > asil klin wrote: >> >> Hi all, >> >> I want to pro

Re: order of index expressions

Ok, So I understand now. You choose the index with the smallest number of matches per key on the average. Unfortunately this doesn't work out so well for me. I am doing a query in the "edges" columnfamily of a graph database, which should return edges with source and target labels equal to give

Re: Finding the intersection results of column sets of two rows

Hi, @buddhasystem : yes that's well known solution. But obviously when mysql couldnt satisfy my needs, I am here. My question is in context of Cassandra, if it possible to achieve intersection result set of columns in two rows, by the way I spoke about. @Edward: yes that I know but how does that

Re: Using a synchronized counter that keeps track of no of users on the application & using it to allot UserIds/ keys to the new users after sign up

If you mix mysql and Cassandra you risk creating a single point of failure around the mysql system. If you have use data that changes infrequently, a row cache in cassandra will give you fast reads. Aaron On 5/02/2011, at 8:13 AM, Aklin_81 wrote: > Thanks so much Ryan for the links; I'll def

Re: postgis > cassandra?

Here is a recent presentation from simplegeo.com that may provide some inspiration http://strangeloop2010.com/system/talks/presentations/000/014/495/Malone-DimensionalDataDHT.pdf Can you provide some more details on the data you want to store and queries you want to run ? Aaron On 6/02/2011,

Re: Finding the intersection results of column sets of two rows

Is it possible for you to dernormalise and write all the intersection values? Will depend on how many I guess. The other alternative is to pull back more data that you need and the intersection in code in the client. Hope that helps. Aaron On 7/02/2011, at 7:11 AM, Aklin_81 wrote: > Hi, >

Re: Ruby thrift is trying to write Time as string

Is there something missing from the error stack? I'm not sure what the actual error is, I also am not really a ruby coder :)Can you provide your schema definition and the data you are trying to insert? Aaron On 06 Feb, 2011,at 07:12 PM, Joshua Partogi wrote:Hi,I don't know whether my assumption is

Re: Finding the intersection results of column sets of two rows

In theory, you should be able to do joins by creating an extra column in one column family, holding the "foreign key" of the matching row in the other family. This assumes that the info you are joining on is available in both CFs (is not some sort of functional transformation). I have just fo

Cassandra Thrift calls block indefinitely

Hi All, This is the first time I see this. I am using Hector for a bulk load into a 3 node Cassandra 0.7.0 cluster. I have been doing this for a while now but this time the load was more intense compared to the ones before and it was running from a single client machine because I was afraid to ove

Re: Finding the intersection results of column sets of two rows

Thanks Aaron & Shaun, ** I think my question might have been unclear to some of you. So I would again explain my problem(& solution which I thought of) for the sake of clarity:- Consider I have 2 rows. 1st row contains 60-70 columns and 2nd row contains like in hundre

Re: Finding the intersection results of column sets of two rows

I think my question might have been unclear to some of you. So I would again explain my problem(& solution which I thought of) for the sake of clarity:- Consider I have 2 rows. 1st row contains 60-70 columns and 2nd row contains like in hundreds of thousands columns. Both the columns sets are al

Does variation in no of columns in rows over the column family has any performance impact ?

Does huge variation in no. of columns in rows, over the column family has *any* impact on the performance ? Can I have like just 100 columns in some rows and like hundred thousands of columns in another set of rows, without any downsides ?

Re: Finding the intersection results of column sets of two rows

Ah -- ok. So (I'm also pretty new to Cassandra, but) I believe that your solution works... just as far as I know you might have to query for those 60-70 columns individually. If you wanted to optimize, you could create a bloom filter for the columns in row 2, and first get it, and then only que

seed node failure crash the whole cluster

cassandra version: 0.7 client library: scale7-pelops / 1.0-RC1-0.7.0-SNAPSHOT cluster: 3 machines (A, B, C) details: it works perfectly when all 3 machines are up and running but if the seed machine is down, the problems happen: 1) new client connection cannot be established 2) if a client ke