deleting keys
i use get_range_slice to get the list of keys, then i call client.remove(keyspace, key, columnFamily, timestamp, ConsistencyLevel.ALL); to delete the record but i still have the keys. why? can i do it otherwise?
Re : Re : Re : get_range_slices result
what i want is that i get the records in the same order wich they were inserted. how can i get this using any type of comparator type if there is a code java for this it can be useful. De : aaron morton aa...@thelastpickle.com À : user@cassandra.apache.org Envoyé le : Mardi 28 Juin 2011 12h40 Objet : Re: Re : Re : get_range_slices result First thing is you really should upgrade from 0.6, the current release is 0.8. Info on time uuid's http://wiki.apache.org/cassandra/FAQ#working_with_timeuuid_in_java If you are using a higher level client like Hector or Pelops it will take care of encoding for you. Cheers - Aaron Morton Freelance Cassandra Developer @aaronmorton http://www.thelastpickle.com On 28 Jun 2011, at 22:20, karim abbouh wrote: can i have an example for using TimeUUIDType as comparator in a client java code. De : karim abbouh karim_...@yahoo.fr À : user@cassandra.apache.org user@cassandra.apache.org Envoyé le : Lundi 27 Juin 2011 17h59 Objet : Re : Re : get_range_slices result i used TimeUUIDType as type in storage-conf.xml file ColumnFamily Name=table CompareWith=TimeUUIDType / and i used it as comparator in my java code, but in the execution i get exception : Erreur --java.io.UnsupportedEncodingException: TimeUUIDType how can i write it? BR De : David Boxenhorn da...@citypath.com À : user@cassandra.apache.org Cc : karim abbouh karim_...@yahoo.fr Envoyé le : Vendredi 24 Juin 2011 11h25 Objet : Re: Re : get_range_slices result You can get the best of both worlds by repeating the key in a column, and creating a secondary index on that column. On Fri, Jun 24, 2011 at 1:16 PM, Sylvain Lebresne sylv...@datastax.com wrote: On Fri, Jun 24, 2011 at 10:21 AM, karim abbouh karim_...@yahoo.fr wrote: i want get_range_slices() function returns records sorted(orded) by the key(rowId) used during the insertion. is it possible? You will have to use the OrderPreservingPartitioner. This is no without inconvenience however. See for instance http://wiki.apache.org/cassandra/StorageConfiguration#line-100 or http://ria101.wordpress.com/2010/02/22/cassandra-randompartitioner-vs-orderpreservingpartitioner/ that give more details on the pros and cons (the short version being that the main advantage of OrderPreservingPartitioner is what you're asking for, but it's main drawback is that load-balancing the cluster will likely be very very hard). In general the advice is to stick with RandomPartitioner and design a data model that avoids needing range slices (or at least needing that the result is sorted). This is very often not too hard and more efficient, and much more simpler than to deal with the load balancing problems of OrderPreservingPartitioner. -- Sylvain De : aaron morton aa...@thelastpickle.com À : user@cassandra.apache.org Envoyé le : Jeudi 23 Juin 2011 20h30 Objet : Re: get_range_slices result Not sure what your question is. Does this help ? http://wiki.apache.org/cassandra/FAQ#range_rp Cheers - Aaron Morton Freelance Cassandra Developer @aaronmorton http://www.thelastpickle.com On 23 Jun 2011, at 21:59, karim abbouh wrote: how can get_range_slices() function returns sorting key ? BR
Re : Re : get_range_slices result
can i have an example for using TimeUUIDType as comparator in a client java code. De : karim abbouh karim_...@yahoo.fr À : user@cassandra.apache.org user@cassandra.apache.org Envoyé le : Lundi 27 Juin 2011 17h59 Objet : Re : Re : get_range_slices result i used TimeUUIDType as type in storage-conf.xml file ColumnFamily Name=table CompareWith=TimeUUIDType / and i used it as comparator in my java code, but in the execution i get exception : Erreur --java.io.UnsupportedEncodingException: TimeUUIDType how can i write it? BR De : David Boxenhorn da...@citypath.com À : user@cassandra.apache.org Cc : karim abbouh karim_...@yahoo.fr Envoyé le : Vendredi 24 Juin 2011 11h25 Objet : Re: Re : get_range_slices result You can get the best of both worlds by repeating the key in a column, and creating a secondary index on that column. On Fri, Jun 24, 2011 at 1:16 PM, Sylvain Lebresne sylv...@datastax.com wrote: On Fri, Jun 24, 2011 at 10:21 AM, karim abbouh karim_...@yahoo.fr wrote: i want get_range_slices() function returns records sorted(orded) by the key(rowId) used during the insertion. is it possible? You will have to use the OrderPreservingPartitioner. This is no without inconvenience however. See for instance http://wiki.apache.org/cassandra/StorageConfiguration#line-100 or http://ria101.wordpress.com/2010/02/22/cassandra-randompartitioner-vs-orderpreservingpartitioner/ that give more details on the pros and cons (the short version being that the main advantage of OrderPreservingPartitioner is what you're asking for, but it's main drawback is that load-balancing the cluster will likely be very very hard). In general the advice is to stick with RandomPartitioner and design a data model that avoids needing range slices (or at least needing that the result is sorted). This is very often not too hard and more efficient, and much more simpler than to deal with the load balancing problems of OrderPreservingPartitioner. -- Sylvain De : aaron morton aa...@thelastpickle.com À : user@cassandra.apache.org Envoyé le : Jeudi 23 Juin 2011 20h30 Objet : Re: get_range_slices result Not sure what your question is. Does this help ? http://wiki.apache.org/cassandra/FAQ#range_rp Cheers - Aaron Morton Freelance Cassandra Developer @aaronmorton http://www.thelastpickle.com On 23 Jun 2011, at 21:59, karim abbouh wrote: how can get_range_slices() function returns sorting key ? BR
Re : Re : get_range_slices result
i used TimeUUIDType as type in storage-conf.xml file ColumnFamily Name=table CompareWith=TimeUUIDType / and i used it as comparator in my java code, but in the execution i get exception : Erreur --java.io.UnsupportedEncodingException: TimeUUIDType how can i write it? BR De : David Boxenhorn da...@citypath.com À : user@cassandra.apache.org Cc : karim abbouh karim_...@yahoo.fr Envoyé le : Vendredi 24 Juin 2011 11h25 Objet : Re: Re : get_range_slices result You can get the best of both worlds by repeating the key in a column, and creating a secondary index on that column. On Fri, Jun 24, 2011 at 1:16 PM, Sylvain Lebresne sylv...@datastax.com wrote: On Fri, Jun 24, 2011 at 10:21 AM, karim abbouh karim_...@yahoo.fr wrote: i want get_range_slices() function returns records sorted(orded) by the key(rowId) used during the insertion. is it possible? You will have to use the OrderPreservingPartitioner. This is no without inconvenience however. See for instance http://wiki.apache.org/cassandra/StorageConfiguration#line-100 or http://ria101.wordpress.com/2010/02/22/cassandra-randompartitioner-vs-orderpreservingpartitioner/ that give more details on the pros and cons (the short version being that the main advantage of OrderPreservingPartitioner is what you're asking for, but it's main drawback is that load-balancing the cluster will likely be very very hard). In general the advice is to stick with RandomPartitioner and design a data model that avoids needing range slices (or at least needing that the result is sorted). This is very often not too hard and more efficient, and much more simpler than to deal with the load balancing problems of OrderPreservingPartitioner. -- Sylvain De : aaron morton aa...@thelastpickle.com À : user@cassandra.apache.org Envoyé le : Jeudi 23 Juin 2011 20h30 Objet : Re: get_range_slices result Not sure what your question is. Does this help ? http://wiki.apache.org/cassandra/FAQ#range_rp Cheers - Aaron Morton Freelance Cassandra Developer @aaronmorton http://www.thelastpickle.com On 23 Jun 2011, at 21:59, karim abbouh wrote: how can get_range_slices() function returns sorting key ? BR
Re : get_range_slices result
i want get_range_slices() function returns records sorted(orded) by the key(rowId) used during the insertion. is it possible? De : aaron morton aa...@thelastpickle.com À : user@cassandra.apache.org Envoyé le : Jeudi 23 Juin 2011 20h30 Objet : Re: get_range_slices result Not sure what your question is. Does this help ? http://wiki.apache.org/cassandra/FAQ#range_rp Cheers - Aaron Morton Freelance Cassandra Developer @aaronmorton http://www.thelastpickle.com On 23 Jun 2011, at 21:59, karim abbouh wrote: how can get_range_slices() function returns sorting key ? BR
get_range_slices result
how can get_range_slices() function returns sorting key ? BR
Re : last record rowId
is there any way to remember the keys (rowId) inserted in cassandra database? B.R De : Jonathan Ellis jbel...@gmail.com À : user@cassandra.apache.org Cc : karim abbouh karim_...@yahoo.fr Envoyé le : Mercredi 15 Juin 2011 18h05 Objet : Re: last record rowId You're better served using UUIDs than numeric row IDs for surrogate keys. (Of course natural keys work fine too.) On Wed, Jun 15, 2011 at 9:16 AM, Utku Can Topçu u...@topcu.gen.tr wrote: As far as I can tell, this functionality doesn't exist. However you can use such a method to insert the rowId into another column within a seperate row, and request the latest column. I think this would work for you. However every insert would need a get request, which I think would be performance issue somehow. Regards, Utku On Wed, Jun 15, 2011 at 11:14 AM, karim abbouh karim_...@yahoo.fr wrote: in my java application,when we try to insert we should all the time know the last rowId in order the insert the new record in rowId+1,so for that we should save this rowId in a file is there other way to know the last record rowId? thanks B.R -- Jonathan Ellis Project Chair, Apache Cassandra co-founder of DataStax, the source for professional Cassandra support http://www.datastax.com
client API
i use jdk1.6 to install and launch cassandra in a linux platform,but can i use jdk1.5 for my cassandra Client ?
last record rowId
in my java application,when we try to insert we should all the time know the last rowId in order the insert the new record in rowId+1,so for that we should save this rowId in a file is there other way to know the last record rowId? thanks B.R
Re : pb deletion
i see that the problem happens when i try to remove records from my application but these records were created before from CLI. is there a explication for this? De : Peter Schuller peter.schul...@infidyne.com À : user@cassandra.apache.org Envoyé le : Vendredi 27 Mai 2011 19h05 Objet : Re: pb deletion i use cassandra database replicated in two servers,when want to delete a record using this line : client.remove(keyspace, sKey, new ColumnPath(columnFamily), timestamp, ConsistencyLevel.ONE); but when i check,i see that the record still exist! Are you using a real timestamp such that the deletion is stamped higher than the insertion? -- / Peter Schuller
pb deletion
i use cassandra database replicated in two servers,when want to delete a record using this line : client.remove(keyspace, sKey, new ColumnPath(columnFamily), timestamp, ConsistencyLevel.ONE); but when i check,i see that the record still exist! any idea BR
Re : selecting data
is there a way to set for a column of the same key a set of value ? De : Watanabe Maki watanabe.m...@gmail.com À : user@cassandra.apache.org user@cassandra.apache.org Envoyé le : Jeu 19 mai 2011, 17h 38min 39s Objet : Re: selecting data Cassandra is not a RDBMS. Only you can do is search on a key, or you need full scan. You need to design your schema carefully as your application needs. On 2011/05/20, at 1:11, karim abbouh karim_...@yahoo.fr wrote: i'm new using cassandra database, i want to get data as in relationnel database: select * from table where field=value; i see using CLI we have just the followings commands : get ksp.cf['key'] Get a slice of columns. get ksp.cf['key']['super'] Get a slice of sub columns. get ksp.cf['key']['col'] Get a column value. get ksp.cf['key']['super']['col'] Get a sub column value. is there a way for that. i think using java API is possible. cassandra version : 6.0.12 thanks for help
Re : Re : selecting data
a storage-conf.xml is read just at the starting of cassandra? is there a way to add a column family dynamically? BR De : karim abbouh karim_...@yahoo.fr À : user@cassandra.apache.org Envoyé le : Ven 20 mai 2011, 12h 48min 54s Objet : Re : selecting data is there a way to set for a column of the same key a set of value ? De : Watanabe Maki watanabe.m...@gmail.com À : user@cassandra.apache.org user@cassandra.apache.org Envoyé le : Jeu 19 mai 2011, 17h 38min 39s Objet : Re: selecting data Cassandra is not a RDBMS. Only you can do is search on a key, or you need full scan. You need to design your schema carefully as your application needs. On 2011/05/20, at 1:11, karim abbouh karim_...@yahoo.fr wrote: i'm new using cassandra database, i want to get data as in relationnel database: select * from table where field=value; i see using CLI we have just the followings commands : get ksp.cf['key'] Get a slice of columns. get ksp.cf['key']['super'] Get a slice of sub columns. get ksp.cf['key']['col'] Get a column value. get ksp.cf['key']['super']['col'] Get a sub column value. is there a way for that. i think using java API is possible. cassandra version : 6.0.12 thanks for help
