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From Subodh Nijsure <subodh.nijs...@gmail.com>
Subject Re: Strange select result when using date grater than query
Date Sun, 17 Aug 2014 14:04:44 GMT
I am in PST ( Oakland ).

I am storing the timestamp in UTC in my insert code, and I see that
cqlsh converts the timestamp to local timezone? i.e.  if I set TZ=EST
cqlsh shows me time stamps in EST like this for the same data set.

SELECT asset_id,event_time,sensor_type, temperature,humidity from
temp_humidity_data where asset_id='2';
 asset_id | event_time               | sensor_type | temperature | humidity
----------+--------------------------+-------------+-------------+----------
        2 | 2014-08-17 05:33:16-0500 |           1 |      74.768 |   65.768
        2 | 2014-08-17 05:33:17-0500 |           1 |      67.228 |   91.228
        2 | 2014-08-17 05:33:19-0500 |           1 |       61.97 |    73.97


So for query i though I should be giving time strings in local timezone too, no?

-Subodh

On Sun, Aug 17, 2014 at 5:17 AM, Jack Krupansky <jack@basetechnology.com> wrote:
> Are you more than 7 time zones behind GMT? If so, that would make 03:33 your
> query less than 03:33-0700  Your query is using the default time zone, which
> will be the time zone configured for the coordinator node executing the
> query.
>
> IOW, where are you?
>
> -- Jack Krupansky
>
> -----Original Message----- From: Subodh Nijsure
> Sent: Sunday, August 17, 2014 6:45 AM
> To: user@cassandra.apache.org
> Subject: Strange select result when using date grater than query
>
>
> Hello,
>
> I am fairly new to cassandra so this might be naieve question:
>
> I have table that currently has following entries:
>
> SELECT asset_id,event_time,sensor_type, temperature,humidity from
> temp_humidity_data where asset_id='2';
>
> asset_id | event_time               | sensor_type | temperature | humidity
> ----------+--------------------------+-------------+-------------+----------
>        2 | 2014-08-17 03:33:16-0700 |           1 |      74.768 |   65.768
>        2 | 2014-08-17 03:33:17-0700 |           1 |      67.228 |   91.228
>        2 | 2014-08-17 03:33:19-0700 |           1 |       61.97 |    73.97
>
> Now if I execute a query :
>
> SELECT asset_id,event_time,sensor_type, temperature,humidity from
> temp_humidity_data where asset_id='2' and event_time > '2014-08-17
> 03:33:20'  ALLOW FILTERING;
>
> it gives me back same results (!), I expected it to give me 0 results.
>
> asset_id | event_time               | sensor_type | temperature | humidity
> ----------+--------------------------+-------------+-------------+----------
>        2 | 2014-08-17 03:33:16-0700 |           1 |      74.768 |   65.768
>        2 | 2014-08-17 03:33:17-0700 |           1 |      67.228 |   91.228
>        2 | 2014-08-17 03:33:19-0700 |           1 |       61.97 |    73.97
>
> am I doing something wrong?
>
> Note I have created table   with following options.
>
>            CREATE TABLE temp_humidity_data (
>                asset_id text,
>                event_time timestamp,
>                sensor_serial_number text,
>                sensor_type int,
>                temperature float,
>                humidity float,
>                polling_freq int,
>                PRIMARY KEY(asset_id ,event_time)
>            ) WITH CLUSTERING ORDER BY (event_time ASC)
>            AND caching = '{"keys":"ALL", "rows_per_partition":"ALL"}'
>
> I have also created following indexes:
>
> CREATE INDEX event_time_index ON temp_humidity_data (event_time);
>
> Also of note is, since actual installation I will be running against
> large time series data I have configured  'row_cache_size_in_mb: 20'
>
> I am running cqlsh 5.0.1 , and cassandra version 2.1.0-rc3
>
> Would appreciate any suggestion on why the date grater-than query is
> returning all the results?
>
> -Subodh

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