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From Leonid Ilyevsky <lilyev...@mooncapital.com>
Subject RE: Dynamic CF
Date Fri, 06 Jul 2012 20:49:47 GMT
Indeed the cql 3.0 reference in cassandra11.pdf does not mention the dynamic tables whatsoever.
Now I found the following posting:

http://www.datastax.com/support-forums/topic/flexible-schema-in-cql-3

where the moderator said " Yes, CQL 3 expects all columns to be defined in the metadata".

At this point I am really confused about what direction Cassandra is going. CQL 3 has the
benefit of composite keys, but no dynamic columns.
I thought, the whole point of Cassandra was to provide dynamic tables.

I need to have a huge table to store market quotes, and be able to query it by name and timestamp
(t1 <= t <= t2), therefore I wanted the composite key.
Loading data to such table using prepared statements (CQL 3-based) was very slow, because
it makes a server call for each row.
So I looked at the API way of doing it, using batch_mutate. Unfortunately, it seems that batch_mutate
would not support composite key.

Then I thought of making wide rows, so I store many quotes in one row (few thousand). For
this I really need dynamic table.

I would appreciate any useful suggestion.

-----Original Message-----
From: Leonid Ilyevsky [mailto:lilyevsky@mooncapital.com]
Sent: Friday, July 06, 2012 4:16 PM
To: user@cassandra.apache.org
Subject: RE: Dynamic CF

Thanks Jeremy, but this doesn't work for me. I am using cql3, because I need new features
like composite keys. The manual you pointed to is for 2.0.
I have suspicion that cql3 does not support dynamic tables at all. Is there a manual for cql3?

-----Original Message-----
From: Jeremy Hanna [mailto:jeremy.hanna1234@gmail.com]
Sent: Friday, July 06, 2012 4:06 PM
To: user@cassandra.apache.org
Subject: Re: Dynamic CF

you can use the cqlsh help but it will eventually refer you to a cql reference such as this
one that says what the options are.  Looks like you need just 'default_validation'.

http://www.datastax.com/docs/1.0/references/cql/index#cql-column-family-storage-parameters

On Jul 6, 2012, at 2:13 PM, Leonid Ilyevsky wrote:

> Can I create a dynamic Cf using cql3? What is the syntax?
>
> Here is what I tried:
>
>
> cqlsh:test> create table mytest (
>         ... asset ascii, datetime int, count int, primary key(asset, datetime) )
>         ...  with default_validation_class = double;
> Bad Request: default_validation_class is not a valid keyword argument for CREATE TABLE
>
> This email, along with any attachments, is confidential and may be legally privileged
or otherwise protected from disclosure. Any unauthorized dissemination, copying or use of
the contents of this email is strictly prohibited and may be in violation of law. If you are
not the intended recipient, any disclosure, copying, forwarding or distribution of this email
is strictly prohibited and this email and any attachments should be deleted immediately. This
email and any attachments do not constitute an offer to sell or a solicitation of an offer
to purchase any interest in any investment vehicle sponsored by Moon Capital Management LP
("Moon Capital"). Moon Capital does not provide legal, accounting or tax advice. Any statement
regarding legal, accounting or tax matters was not intended or written to be relied upon by
any person as advice. Moon Capital does not waive confidentiality or privilege as a result
of this email.


This email, along with any attachments, is confidential and may be legally privileged or otherwise
protected from disclosure. Any unauthorized dissemination, copying or use of the contents
of this email is strictly prohibited and may be in violation of law. If you are not the intended
recipient, any disclosure, copying, forwarding or distribution of this email is strictly prohibited
and this email and any attachments should be deleted immediately.  This email and any attachments
do not constitute an offer to sell or a solicitation of an offer to purchase any interest
in any investment vehicle sponsored by Moon Capital Management LP ("Moon Capital"). Moon Capital
does not provide legal, accounting or tax advice. Any statement regarding legal, accounting
or tax matters was not intended or written to be relied upon by any person as advice. Moon
Capital does not waive confidentiality or privilege as a result of this email.

This email, along with any attachments, is confidential and may be legally privileged or otherwise
protected from disclosure. Any unauthorized dissemination, copying or use of the contents
of this email is strictly prohibited and may be in violation of law. If you are not the intended
recipient, any disclosure, copying, forwarding or distribution of this email is strictly prohibited
and this email and any attachments should be deleted immediately.  This email and any attachments
do not constitute an offer to sell or a solicitation of an offer to purchase any interest
in any investment vehicle sponsored by Moon Capital Management LP ("Moon Capital"). Moon Capital
does not provide legal, accounting or tax advice. Any statement regarding legal, accounting
or tax matters was not intended or written to be relied upon by any person as advice. Moon
Capital does not waive confidentiality or privilege as a result of this email.

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