I'm not doing schema migration, but I suspect my lack of experience
and understanding of column-based data is clouding the issue. What I
have is 2 pieces of information, let's call them LH and RH and a
single long value representing the link between them, S. The data
needs to be ordered by S, so the data I have in mind looks like this:
CF {
LH1 {
S1 {
RH1
RH2
RH3
}
S2 {
RH2
RH3
}
}
LH2 {
S1 {
RH1
RH2
}
S2 {
RH3
RH4
}
}
}
At some point in the application lifecycle an event is received to
indicate the S value needs updating for the LH,RH pair. Initially I
was thinking of using a second column family as an index, and would
look like:
LH1 {
RH1 : S1
RH2 : S1
.....
}
And using that to key into the structure above, but then was trying to
figure out if I could bypass the second index completely.
For other operations I need to extract the Top X entries for each row
key (LH)- does this sound sane or am I still stuck in RDBMS land?
On Wed, Mar 24, 2010 at 12:56 PM, Jeremy Dunck <jdu...@gmail.com> wrote:
> On Wed, Mar 24, 2010 at 4:57 AM, Colin Vipurs <zodiac...@gmail.com> wrote:
> ...
>> ColumnFamily {
>> 'key1' {
>> 'SuperColumn1' {
>> 'Column1' : <somevalue>
>> 'Column2' : <somevalue>
>> }
>> 'SuperColumn2' {
>> 'Column3' : <somevalue>
>> }
>> }
>> 'key2' {
>> 'SuperColumn1' {
>> 'Column1' : <somevalue>
>> }
>> }
>> }
>>
>> Could I get all keys/supercolumns where 'Column1' exists? fyi I'm
>> using the Hector Java client for my work.
>
> I think maybe you're asking because you want to perform schema migration.
>
> If so, one option is to have client-side code that mutates to the
> later schema upon encountering the old schema.
> Another option is to have a schema-versioning column, and have a job
> that fetches and mutates records w/ the old schema.
>
> If there are other ways of handling schema migration, I'm curious?
>
--
Maybe she awoke to see the roommate's boyfriend swinging from the
chandelier wearing a boar's head.
Something which you, I, and everyone else would call "Tuesday", of course.
