created_at is stored differently in mysql then in sqlite.
sqlite stores the dates like: 2011-04-14 22:52:52.758612
and mysql stores the date like: 2011-04-14 22:52:52 (possible rounded)
When I output the date with json formatting, it’s returned as 2011-04-14T22:52:52Z regardless of the underlaying db. But in another part of my application I request all items with a date newer then the above. However since “2011-04-14 22:52:52.758612” is bigger then “2011-04-14 22:52:52” I get the same item again when I query against sqlite (or postgresql actually).
In my model I have the following scope defined: scope :since, lambda {|time| where(“updated_at > ?”, time) }
which I’m using for getting all news items since a current date.
Are you saying that if you fetch a record and then ask for records
where created_at is greater than that records created_at (so no
messing with json in between) that you get the same record again. Or
using your scope
record1 = Model.find( some conditions )
records = Model.since( record1.created_at )
that you get record1 again?
created_at is stored differently in mysql then in sqlite.
sqlite stores the dates like: 2011-04-14 22:52:52.758612
and mysql stores the date like: 2011-04-14 22:52:52 (possible rounded)
When I output the date with json formatting, it's returned as
2011-04-14T22:52:52Z regardless of the underlaying db. But in another part
of my application I request all items with a date newer then the above.
However since "2011-04-14 22:52:52.758612" is bigger then "2011-04-14
22:52:52" I get the same item again when I query against sqlite (or
postgresql actually).
In my model I have the following scope defined: scope :since, lambda {|time|
where("updated_at > ?", time) }
which I'm using for getting all news items since a current date.
Are you saying that if you fetch a record and then ask for records
where created_at is greater than that records created_at (so no
messing with json in between) that you get the same record again. Or
using your scope
record1 = Model.find( some conditions )
records = Model.since( record1.created_at )
that you get record1 again?
Yes, since record1.created_at returns the seconds without decimals.
created_at is stored differently in mysql then in sqlite.
sqlite stores the dates like: 2011-04-14 22:52:52.758612
and mysql stores the date like: 2011-04-14 22:52:52 (possible rounded)
When I output the date with json formatting, it's returned as
2011-04-14T22:52:52Z regardless of the underlaying db. But in another part
of my application I request all items with a date newer then the above.
However since "2011-04-14 22:52:52.758612" is bigger then "2011-04-14
22:52:52" I get the same item again when I query against sqlite (or
postgresql actually).
In my model I have the following scope defined: scope :since, lambda {|time|
where("updated_at > ?", time) }
which I'm using for getting all news items since a current date.
Are you saying that if you fetch a record and then ask for records
where created_at is greater than that records created_at (so no
messing with json in between) that you get the same record again. Or
using your scope
record1 = Model.find( some conditions )
records = Model.since( record1.created_at )
that you get record1 again?
Yes, since record1.created_at returns the seconds without decimals.
Can you confirm that you have you tried exactly what I have suggested?
Note that the Time class does allow for fractions of a second.
In sqlite:
> select * from news;
1|shalala|sss|2011-04-14 22:52:52.758612|2011-04-14 22:52:52.758612||||1
But in rails the same record is returned as:
irb(main):001:0> News.first.created_at
=> Thu, 14 Apr 2011 22:52:52 UTC +00:00
All that shows is that it is displayed without fractions when using
the default format. It does not prove that created_at does not
include seconds.
So if I query for records created after 2011-04-14 22:52:52 I get the
same record again.
Querying for records after 2011-04-14 22:52:52 is not necessarily the
same as querying for records after record.created_at. I am not saying
you are wrong, as I am unable to test it myself easily. Just making
sure that what is happening is clear. If Rails writes fractions of a
second to the mysql db but does not read them back into created_at
then I would say that this is a bug.
According the docs for Time.strftime one should be able to display the
milliseconds of a time using %L, [1], however in the console I get
ruby-1.8.7-p302 > Time.now.strftime("%S.%L")
=> "02.%L"
Is %L a Ruby 1.9 enhancement?
Answering my own question, yes this appears to be a Ruby 1.9
enhancement. If you are using 1.9 then what happens if in the console
you do
record.created_at.strftime(%H:%M:%S.%L")
