I should have asked where your coordinator node is located. Check its time
zone, relative to GMT.
cqlsh is simply formatting the time stamp for your local display. That is
separate from the actual query execution on the server coordinator node.
cqlsh is merely a "client", not the "server". And separate from the actual
data, which is stored in GMT.
-- Jack Krupansky
-----Original Message-----
From: Subodh Nijsure
Sent: Sunday, August 17, 2014 10:04 AM
To: user@cassandra.apache.org
Subject: Re: Strange select result when using date grater than query
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 <j...@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
