cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Jeremiah Jordan" <JEREMIAH.JOR...@morningstar.com>
Subject RE: one question about cassandra write
Date Fri, 06 Aug 2010 21:52:44 GMT
If you want to be able to get the data over time, you need to store it
in multiple columns.  You can use TimeUUID columns if you need to be
able to get ranges of times through queries.

-----Original Message-----
From: Maifi Khan [mailto:maifi.khan@gmail.com] 
Sent: Friday, August 06, 2010 2:51 PM
To: user@cassandra.apache.org
Subject: one question about cassandra write

Hi
I have a question about the internal of cassandra write.
Say, I already have the following in the database -
(row_x,col_y,val1)

Now if I try to insert
(row_x,col_y,val100), what will happen?
Will it overwrite the old data?
I mean, will it overwrite the data physically or will it keep both the
old version and the new version of the data?
If the later is the case, can I retrieve the old version of the data?

One sample example where I may need this is as follows -
say I want to log the stock price of a particular company over time.
Say company name is the row key and stock price is the column. Then
the stock price column needs to be written repeatedly.
HTH

thanks
Maifi

Mime
View raw message