Hi Sávio, There is no definitive response: it depends on your business model ;-) I just guess here it should be something like the id of some data root.
Take also a look at http://www.datastax.com/dev/blog/schema-in-cassandra-1-1 and look for "partition key", if you want to go through CQL. De : Sávio Teles [mailto:[email protected]] Envoyé : jeudi 3 janvier 2013 14:58 À : [email protected] Objet : Re: Force data to a specific node Hi Dominique, I have the same problem! I would like to place an object in a specific node because I'm working in a spatial application. How should I choose the K1 part to forcing a given object to go to a node? 2013/1/3 DE VITO Dominique <[email protected]<mailto:[email protected]>> Hi Everton, AFAIK, the pb is not forcing data to a specific node, but forcing some kind of data locality. There is things into cql to do it: you define a composite key (K1, K2), and K1 part is used as a rowkey and K2 is used within column name. So, all rows with same K1 are on the same node. See also https://issues.apache.org/jira/browse/CASSANDRA-5054 Dominique De : Everton Lima [mailto:[email protected]<mailto:[email protected]>] Envoyé : mercredi 2 janvier 2013 19:20 À : [email protected]<mailto:[email protected]> Objet : Re: Force data to a specific node We need to do this to minimize the network I/O. We have our own load data balance algorithm. We have some data that is best to process in a local machine. Is it possible? How? 2013/1/2 Edward Sargisson <[email protected]<mailto:[email protected]>> Why would you want to? ________________________________ From: Everton Lima <[email protected]<mailto:[email protected]>> To: Cassandra-User <[email protected]<mailto:[email protected]>> Sent: Wed Jan 02 18:03:49 2013 Subject: Force data to a specific node It is possible to force a data to stay in a specific node? -- Everton Lima Aleixo Bacharel em Ciência da Computação pela UFG Mestrando em Ciência da Computação pela UFG Programador no LUPA -- Everton Lima Aleixo Bacharel em Ciência da Computação pela UFG Mestrando em Ciência da Computação pela UFG Programador no LUPA -- Atenciosamente, Sávio S. Teles de Oliveira voice: +55 62 9136 6996 http://br.linkedin.com/in/savioteles Mestrando em Ciências da Computação - UFG Arquiteto de Software Laboratory for Ubiquitous and Pervasive Applications (LUPA) - UFG
