Take a look at the get_indexed_slices method in the 0.7.0-beta Thrift interface.
-----Original Message----- From: "Christian Decker" <decker.christ...@gmail.com> Sent: Thursday, September 30, 2010 4:38am To: user@cassandra.apache.org Subject: Re: LongType from user input I just read through the tickets on Jira, and it appears that indices are implemented in the 0.7 source tree, but I cannot find any pointer on how to use them. I'll be trying to create a custom CassandraStorage that loads data through the indices, anyone else interested? Regards, Chris On Thu, Sep 30, 2010 at 10:56 AM, Aaron Morton <aa...@thelastpickle.com>wrote: > AFAIK indexes are still in dev. The only example is in the system_tests.py > in the source tree. > > Aaron > > > On 30 Sep 2010, at 20:10, Christian Decker <decker.christ...@gmail.com> > wrote: > > Apparently I have blanked the 0.7 completely out of my memory. I was trying > to implement application layer indices and ignored the fact that Cassandra > 0.7 is implementing them by default. I found ticket CASSANDRA-749 about the > indices and am reading through the code right now, but is there a higher > level overview and a tutorial on how to get things started with these > indices (and maybe some inner workings)? This might actually solve all of my > problems I'm having right now :-) > > Regards, > Chris > > > On Mon, Sep 27, 2010 at 3:45 AM, Aaron Morton < <aa...@thelastpickle.com> > aa...@thelastpickle.com> wrote: > >> The only thing I can think of is that values need to be in the correct >> byte format when used in indexes in 0.7. Take a look at the types.py module >> in the pycassa client <http://github.com/pycassa/pycassa> >> http://github.com/pycassa/pycassa for an example of which values need to >> be byte packed. >> >> How is your pig function working against cassandra? Is it using the >> ColumnFamilyRecordReader? . The code in the internal RowIterator for that >> class has an example calling the cluster to get to the comparators. >> >> Aaron >> >> >> On 27 Sep, 2010,at 03:11 AM, Christian Decker <<decker.christ...@gmail.com> >> decker.christ...@gmail.com> wrote: >> >> Hi Aaron, >> >> what changes can I expect in the 0.7 release regarding Comparison and >> Parameters? My problem is mainly that I want to take Strings from stdin (or >> Pig Scripts for that matter) and convert them in such a way that they are >> interpreted correctly and converted to the corresponding byte representation >> to use them in column names and keys. >> >> Regards, >> Chris >> >> On Sun, Sep 26, 2010 at 5:20 AM, Aaron Morton < <aa...@thelastpickle.com> >> aa...@thelastpickle.com> wrote: >> >>> Things a changing in v0.7, the row keys are byte arrays. >>> >>> Not sure I understand your other concerns. >>> >>> Aaron >>> >>> >>> On 25 Sep 2010, at 08:10, Christian Decker <<decker.christ...@gmail.com> >>> decker.christ...@gmail.com> wrote: >>> >>> >>> Thanks for your quick answer, I think I'll use an affix to sort of cast >>> the keys, ranges and others from their textual representation (from Pig) to >>> the desired byte representation, since I just noticed that the keys for the >>> rows themselfs are always UTF8 interpreted, and since I want to make >>> key-range as well as slice queries, I'll be better off this way I think. >>> I'll just add a 'L' for Long and 'U' for UUID (of any kind). >>> Or is there a better way that I just can't see from my beginners angle? >>> :-)thing >>> >>> Regards, >>> Chris >>> >>> >>> On Fri, Sep 24, 2010 at 6:35 PM, Tyler Hobbs < >>> <ty...@riptano.com><ty...@riptano.com> >>> ty...@riptano.com> wrote: >>> >>>> Yes, you can use describe_keyspace() and then look through the results. >>>> It's a little ugly in 0.6, but it works >>>> >>>> - Tyler >>>> >>>> >>>> >>>> On Fri, Sep 24, 2010 at 11:25 AM, Christian Decker >>>> <<decker.christ...@gmail.com><decker.christ...@gmail.com> >>>> decker.christ...@gmail.com> wrote: >>>> >>>>> Well I'm writing a loading function for Pig, and as it happens I want >>>>> to be able to load slices from cassandra which are specified in the pig >>>>> script (thus the input from stdin) but the ColumnFamily from which to read >>>>> the data is another parameter and some of the CFs have UTF8, UUID, >>>>> TimeUUID >>>>> or Long types for their keys and columns, so simply converting everything >>>>> I >>>>> get to an 8byte long would break compatibility with the others. >>>>> Now thinking about it I attacked the whole problem in a weird way, >>>>> since UUID types won't work either. >>>>> So let me change my question slightly, is there a way in 0.6 to detect >>>>> the compareWith type on a running cluster? That way I could convert it to >>>>> the right type :D >>>>> >>>>> Regards, >>>>> Chris >>>>> >>>>> >>>>> On Fri, Sep 24, 2010 at 6:09 PM, Tyler Hobbs < >>>>> <ty...@riptano.com><ty...@riptano.com> >>>>> ty...@riptano.com> wrote: >>>>> >>>>>> I'm not sure I understand why using this with multiple column families >>>>>> prevents you from converting it. Could you clarify this? >>>>>> >>>>>> >>>>>> >>>>>> On Fri, Sep 24, 2010 at 10:56 AM, Christian Decker >>>>>> <<decker.christ...@gmail.com><decker.christ...@gmail.com> >>>>>> decker.christ...@gmail.com> wrote: >>>>>> >>>>>>> Hi all, >>>>>>> >>>>>>> I'm having quite a dilemma with the CompareWith attribute. The >>>>>>> Problem is that I have numeric IDs that I'd like to use as row keys, >>>>>>> only >>>>>>> that I also have to offer a possibility to let users input them from std >>>>>>> input. Since I cannot ask my users to input an 8byte sequence >>>>>>> representing >>>>>>> the ID they'd like, I was about to turn to UTF8, when I remembered that >>>>>>> they >>>>>>> are compared lexicographically, so that 100 actually comes before 2, >>>>>>> which >>>>>>> kills key slices. Also I cannot just code a converter in since this is >>>>>>> supposed to be a used with multiple columnfamilies, so just converting >>>>>>> an >>>>>>> integer read into 8bytes isn't going to work either. >>>>>>> Any tricks for this one? >>>>>>> >>>>>>> Regards, >>>>>>> Chris >>>>>>> >>>>>> >>>>>> >>>>> >>>> >>> >> >
