You are viewing a plain text version of this content. The canonical link for it is here.
Posted to commits@cassandra.apache.org by "Adam Holmberg (Jira)" <ji...@apache.org> on 2020/08/13 18:44:00 UTC
[jira] [Commented] (CASSANDRA-14853) Change default timestamp
format to output only milliseconds, not microseconds
[ https://issues.apache.org/jira/browse/CASSANDRA-14853?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17177249#comment-17177249 ]
Adam Holmberg commented on CASSANDRA-14853:
-------------------------------------------
I looked at the code for this briefly and there's not a great way to do it with the way that formatting is parameterized right now.
By default it will use [this format|https://github.com/apache/cassandra/blob/54ebb19720225e176bc93e6dbc9e8943fa5e3bfc/pylib/cqlshlib/formatting.py#L115] to format `datetime`.
[strptime|https://docs.python.org/3/library/datetime.html#strftime-and-strptime-format-codes] does not provide a way of specifying precision in the pattern.
Because of the way the [format function|https://github.com/apache/cassandra/blob/54ebb19720225e176bc93e6dbc9e8943fa5e3bfc/pylib/cqlshlib/formatting.py#L115] is parameterized, we can't simply pick the returned string apart and remove digits.
Separately from this, the parsing I've introduced in CASSANDRA-15976 actually does parse the format output by cqlsh, so wrapping a value back works.
I suggest we leave this formatting alone for now and let the better parsing on the server take care of this problem.
{noformat}
cqlsh:test> create table t1(tm timestamp primary key, t text);
cqlsh:test> insert into t1(tm, t) values(toTimestamp(now()), 't');
cqlsh:test> insert into t1(tm, t) values(toTimestamp(now()), 't2');
cqlsh:test> select * from t1;
tm | t
-----------------------------+----
2020-08-13 18:38:34.3f+0000 | t2
2020-08-13 18:38:27.3f+0000 | t
(2 rows)
cqlsh:test> select * from t1 where tm = '2020-08-13 18:38:34.598000+0000';
tm | t
---------------------------------+----
2020-08-13 18:38:34.598000+0000 | t2
(1 rows)
cqlsh:test>
{noformat}
wdyt?
> Change default timestamp format to output only milliseconds, not microseconds
> -----------------------------------------------------------------------------
>
> Key: CASSANDRA-14853
> URL: https://issues.apache.org/jira/browse/CASSANDRA-14853
> Project: Cassandra
> Issue Type: Improvement
> Components: Tool/cqlsh
> Environment: Reproduced in trunk
> Reporter: Alex Ott
> Priority: Normal
> Labels: cqlsh
>
> By default cqlsh outputs the timestamp column with microseconds precision, like this:
> {noformat}
> cqlsh:test> create table t1(tm timestamp primary key, t text);
> cqlsh:test> insert into t1(tm, t) values(toTimestamp(now()), 't');
> cqlsh:test> insert into t1(tm, t) values(toTimestamp(now()), 't2');
> cqlsh:test> SELECT * from t1;
> tm | t
> ---------------------------------+----
> 2018-10-27 18:01:54.738000+0000 | t2
> 2018-10-27 18:01:52.599000+0000 | t
> (2 rows)
> {noformat}
> But if I want to use the value that is output on the screen in my query, I get an error:
> {noformat}
> cqlsh:test> select * from t1 where tm = '2018-10-27 18:01:54.738000+0000';
> InvalidRequest: Error from server: code=2200 [Invalid query] message="Unable to coerce '2018-10-27 18:01:54.738000+0000' to a formatted date (long)"
> {noformat}
> But if I manually round it to milliseconds, then everything works:
> {noformat}
> cqlsh:test> select * from t1 where tm = '2018-10-27 18:01:54.738+0000';
> tm | t
> ---------------------------------+----
> 2018-10-27 18:01:54.738000+0000 | t2
> (1 rows)
> {noformat}
> It would be much easier user's experience if we use the same format for output & input data, because right now this leads to errors, that often not really understandable by novice users.
> P.S. I know about cqlshrc, but not every user has it configured.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: commits-unsubscribe@cassandra.apache.org
For additional commands, e-mail: commits-help@cassandra.apache.org