I think I get the basics of what you want to achieve. Side note, the sample
insert seems to have a typo for the transaction time
For the first query, I would store the data using weatherstation _id as the
key. The create table statement might look like this.
CREATE TABLE weatherstation (
weathers
Thanks for the response Peter. I used the temperature table because its the
most common example on CQL timeseries and I thought I would reuse it. From
some of the responses, looks like I was wrong.
event_time is the time the event happened. So yes it is valid time. I was
trying to see if I can get
I've built several different bi-temporal databases over the year for a
variety of applications, so I have to ask "why are you modeling it this
way?"
Having a temperatures table doesn't make sense to me. Normally a
bi-temporal database has transaction time and valid time. The transaction
time is th
I had forgotten, but there is a new tuple notation to iterate over more
than one clustering column in C* 2.0.6:
https://issues.apache.org/jira/browse/CASSANDRA-4851
For example,
SELECT ... WHERE (c1, c2) > (1, 0)
There's an example in the CQL spec:
https://cassandra.apache.org/doc/cql3/CQL.html
The simple, easy way to look at this is that you can use a range when the
data will be contiguous.Only by allowing only the last clustering column to
use a range can Cassandra be assured that the rows selected by the range
will be contiguous (a "slice.") The point is that Cassandra is designed for
As you point out, there's not really a node-based problem with your
query from a performance point of view. This is a limitation of CQL in
that, cql wants to slice one section of a partition's row (no matter how
big the section is). In your case, you are asking to slice multiple
sections of a p
Perhaps you should learn more about Cassandra before you ask such questions.
It's easy if you just look at the readily accessible docs.
ml
On Sat, Feb 14, 2015 at 6:05 PM, Raj N wrote:
> I don't think thats solves my problem. The question really is why can't we
> use ranges for both time colum
I don't think thats solves my problem. The question really is why can't we
use ranges for both time columns when they are part of the primary key.
They are on 1 row after all. Is this just a CQL limitation?
-Raj
On Sat, Feb 14, 2015 at 3:35 AM, DuyHai Doan wrote:
> "I am trying to get the state
"I am trying to get the state as of a particular transaction_time"
--> In that case you should probably define your primary key in another
order for clustering columns
PRIMARY KEY (weatherstation_id,transaction_time,event_time)
Then, select * from temperatures where weatherstation_id = 'foo' an
Has anyone designed a bi-temporal table in Cassandra? Doesn't look like I
can do this using CQL for now. Taking the time series example from well
known modeling tutorials in Cassandra -
CREATE TABLE temperatures (
weatherstation_id text,
event_time timestamp,
temperature text,
PRIMARY KEY (weather
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