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List:       cassandra-dev
Subject:    Re: Fw: Fwd: CQL & Thrift
From:       Vivek Mishra <vivek.mishra () yahoo ! com>
Date:       2013-08-30 18:32:00
Message-ID: 1377887520.32593.YahooMailNeo () web162405 ! mail ! bf1 ! yahoo ! com
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True. but in my example i did not drop any column:

update column family user with key_validation_class='UTF8Type' and \
column_metadata=[{column_name:last_name, validation_class:'UTF8Type', \
index_type:KEYS},{column_name:first_name, validation_class:'UTF8Type', \
index_type:KEYS}];



And surprisingly:

alter table user add first_name text;
alter table user add last_name text;


It gives me back column with values(on cqlsh), but still no indexes.  


They have two different schema systems, two different access languages, there is some \
compatibility between the two, but working out which feature sets mix and match is \
more effort then just picking one. <Vivek> If two different schema systems and two \
different languages. But why can't they differently rather than a random behavior. I \
haven't looked into the code, so not sure if my question is valid or not </Vivek>


Thanks for your reply.

-Vivek

________________________________
 From: Edward Capriolo <edlinuxguru@gmail.com>
To: "dev@cassandra.apache.org" <dev@cassandra.apache.org>; Vivek Mishra \
                <vivek.mishra@yahoo.com> 
Sent: Friday, August 30, 2013 11:53 PM
Subject: Re: Fw: Fwd: CQL & Thrift
 


This is always so hard to explain but

http://www.datastax.com/dev/blog/thrift-to-cql3


Get to the part that looks like this:

update column family user_profiles
with key_validation_class = UTF8Type
and comparator = UTF8Type
and column_metadata=[]

"Since the static column values validation types have been dropped, they are not \
available to your client library anymore. In particular, as can be seen in the output \
above, cqlsh display some value in a non human-readable format. And unless the client \
library exposes an easy way to force the deserialization format for a value, such \
deserialization will have to be done manually in client code."

This I think the above is largest reason. Due to the way 'CQL'  wants to present \
'thrift' column familes, you have to lose your 'thrift' notion of schema, because it \
is not compatible with the 'cql' notion of schema. I am wrapping 'thrift' and 'cql' \
in quotes because 'CQL' is an access language, but when you define tables as \
non-compact storage they gain 'features' that make them not understandable by non-cql \
clients.

They have two different schema systems, two different access languages, there is some \
compatibility between the two, but working out which feature sets mix and match is \
more effort then just picking one.



On Fri, Aug 30, 2013 at 2:05 PM, Vivek Mishra <vivek.mishra@yahoo.com> wrote:

fyi. Just curious to know the real reason behind "not to mix thrift and CQL3".
> 
> Any pointers?
> 
> -Vivek
> 
> 
> 
> ---------- Forwarded message ----------
> From: Vivek Mishra <mishra.vivs@gmail.com>
> Date: Fri, Aug 30, 2013 at 11:21 PM
> Subject: Re: CQL & Thrift
> To: user@cassandra.apache.org
> 
> 
> 
> Hi,
> I understand that, but i want to understand the reason behind such behavior?  Is it \
> because of maintaining different metadata objects for CQL3 and thrift? 
> Any suggestion?
> 
> -Vivek
> 
> 
> 
> On Fri, Aug 30, 2013 at 11:15 PM, Jon Haddad <jon@jonhaddad.com> wrote:
> 
> If you're going to work with CQL, work with CQL.  If you're going to work with \
> Thrift, work with Thrift.  Don't mix.
> > 
> > 
> > On Aug 30, 2013, at 10:38 AM, Vivek Mishra <mishra.vivs@gmail.com> wrote:
> > 
> > Hi,
> > > If i a create a table with CQL3 as 
> > > 
> > > 
> > > create table user(user_id text PRIMARY KEY, first_name text, last_name text, \
> > > emailid text); 
> > > 
> > > and create index as:
> > > create index on user(first_name);
> > > 
> > > 
> > > then inserted some data as:
> > > insert into user(user_id,first_name,last_name,"emailId") \
> > > values('@mevivs','vivek','mishra','vivek.mishra@impetus.co.in'); 
> > > 
> > > 
> > > 
> > > 
> > > Then if update same column family using Cassandra-cli as:
> > > 
> > > 
> > > update column family user with key_validation_class='UTF8Type' and \
> > > column_metadata=[{column_name:last_name, validation_class:'UTF8Type', \
> > > index_type:KEYS},{column_name:first_name, validation_class:'UTF8Type', \
> > > index_type:KEYS}]; 
> > > 
> > > 
> > > 
> > > 
> > > Now if i connect via cqlsh and explore user table, i can see column \
> > > first_name,last_name are not part of table structure anymore. Here is the \
> > > output: 
> > > 
> > > CREATE TABLE user (
> > > key text PRIMARY KEY
> > > ) WITH
> > > bloom_filter_fp_chance=0.010000 AND
> > > caching='KEYS_ONLY' AND
> > > comment='' AND
> > > dclocal_read_repair_chance=0.000000 AND
> > > gc_grace_seconds=864000 AND
> > > read_repair_chance=0.100000 AND
> > > replicate_on_write='true' AND
> > > populate_io_cache_on_flush='false' AND
> > > compaction={'class': 'SizeTieredCompactionStrategy'} AND
> > > compression={'sstable_compression': 'SnappyCompressor'};
> > > 
> > > 
> > > cqlsh:cql3usage> select * from user;
> > > 
> > > 
> > > user_id
> > > ---------
> > > @mevivs
> > > 
> > > 
> > > 
> > > 
> > > 
> > > 
> > > 
> > > 
> > > 
> > > 
> > > I understand that, CQL3 and thrift interoperability is an issue. But this looks \
> > > to me a very basic scenario. 
> > > 
> > > 
> > > 
> > > 
> > > 
> > > Any suggestions? Or If anybody can explain a reason behind this?
> > > 
> > > 
> > > -Vivek
> > > 
> > > 
> > > 
> > > 
> > > 
> > > 
> > > 
> > > 
> > 



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