topic Set analysis Question in QlikView

Set analysis Question

Sun, 17 Jun 2012 08:54:52 GMT

Hello everyone,

I have a table like this:

DateTime	Status	Tap_Id
01/01/2012 14:00	open	1
01/01/2012 15:00	close	1
02/01/2012 14:00	open	1
02/01/2012 4:30	close	1
02/01/2012 4:45	open	1
03/01/2012 20:00	close	1
03/01/2012 20:00	open	1

I want to build a simple chart that will present for each day and tap the last status - open or close (the biggest datetime for each day)

Thanks in advance.

Re: Set analysis Question

Sun, 17 Jun 2012 15:18:18 GMT

Hi Matan,

Presuming you don't wish to edit the script (which would be the easiest and most efficient way to do this) this is how I would construct my chart:

Dimension: Add calculated dimension of

=date(floor(Datetime))

this will remove the time from the timestamp and group your items as just a date (Date() on it's own migiht work, but I haven't tested it as a dimension)

Expression "latest Status" : =firstsortedvalue(Status, -DateTime)

Firstsorted value takes the first status when you order by "-Datetime" IE the "last" in the day.

Regards,

Erica

Re: Set analysis Question

Mon, 18 Jun 2012 05:19:51 GMT

Thanks....i didnt think about using this function.....

just for the knowledge - can it been done by using set analysis ?

Re: Set analysis Question

Mon, 18 Jun 2012 16:54:59 GMT

yes, but it would be more complicated. Something like

=only( {$<Datetime= {$(=Datetime) } >} Status)

This will search for the "only" value of status where the datetime is the same as the max datetime.

Regards,

Erica

Re: Set analysis Question

Tue, 19 Jun 2012 11:52:19 GMT

Thanks again,

Somehow the set analysis expression isnt working for me.

I would appreciate if you could look in this qvw.

Re: Set analysis Question

perumal_41 — Tue, 19 Jun 2012 12:17:51 GMT

Hi,

I have attached one Application .This Application helpful to u.

Reegards

perumal

Re: Set analysis Question

Tue, 19 Jun 2012 12:22:55 GMT

I was also thinking...

Perumal A: your solution isn't setAnalysis, is it?

A problem in that solution (as well as in the solution with firstSortedValue) is the date 3-1-2012. In this QVW it doesn't appear, while it should. The cause is that the datetime is exactly the same (and the firstSortedValue has >1 record and will be null...) Perhaps this is more a data-cleaning thing?

In SetAnalysis I'm afraid it will be hard, So I wonder what the reaction of Erica Whally is. I think in the load-script then first the max-date must be calculated and available per column, so that then the setanalysis will work...

Re: Set analysis Question

azimabadi — Tue, 19 Jun 2012 12:38:40 GMT

Hi Matan,

first change dimension in your QVW from "Tap_ID" to "date". This make things to look a few better. But problem is your Expression where you have used : DateTime={"=max(DateTime)"}. It's not the way you can use functions in an Expression defination. ofcurse you can define a variable like this :

='only({$<DateTime={"' & =max(DateTime) & '"}>}Status)'

and then write $(varName) as Expression,but max() will be called only one time when QV wants to refresh the chart, not for every row with a different value of max(DateTime).

I think the best way is what Erica has mentioned in first post.

Best Regards

Peyman

Re: Set analysis Question

Tue, 19 Jun 2012 12:40:34 GMT

So that would mean that this is not possible with SetAnalysis, right?

Re: Set analysis Question

azimabadi — Tue, 19 Jun 2012 15:17:03 GMT

I think so, Generaly set analys is for filtering on an expression, for all values. I don't know any way that can be used in the way that you mean.

Re: Set analysis Question

Tue, 19 Jun 2012 17:50:59 GMT

Thank you all for helping me.

I didnt give up.... i will find a way to solve this with set analysis....

Re: Set analysis Question

azimabadi — Thu, 21 Jun 2012 12:39:17 GMT

Pleas write the answer here when you find a way to do this with SA. I'm really interested to see that is this posible with use of SA or not.

Best Regards

Peyman

Re: Set analysis Question

Thu, 21 Jun 2012 17:48:39 GMT

Hi, I've come to the conclusion that you cant achieve this with set analysis, the reason is below:

The reason is, that when you define a set in set analysis it defines the set as if you were making selections in all the data. It doesn''t take into account the dimension or divide up the data by dimension.

So if you include an expression in the set analysis, this is performed first over the full set of data before being applied to each element in the dimension.

so in the example above if you were to reference $(=max([chosen_field]) in the set analysis this would work out the max(chosen_field) for all the data before applying that static max to the dimension. So there is no immediately easy way to use set analysis differently dependant on what was in the dimension.

Hope this helps clarify things!

Erica

Re: Set analysis Question

sebastiandperei — Thu, 23 Aug 2012 00:52:51 GMT

Dear Matan, I like the people that never gives up!!

In first place, with a table with "date" as dimention (if you don't have the "date" field, you could create with a calculated dimention like =Left(date(DateTime),10)), the expression that gives to you the last state is:

=FirstSortedValue(State, -DateTime)

But, for make this with SA, you need to tell to the expression witch values are available. These available values will be only the max for each day. The expression would be:

Only({<DateTime={$(vMaxTime)}>}Status)

Because of sintaxis of SA, you cant use search query inside another search query, and to make that you need to make a variable. In this case, it would be:

='"*'&Concat(left(Timestamp(Aggr(max(DateTime),date)),16),'","*')&'"'

This variable creates a search string, with the values of the max for each day. From inside to outside, Aggr(Max(DateTime), date) gives you the max values aggregated by date. Then, with TimeStamp, you transform it to a timestamp string. I used Left to pick out the seconds, because if you use the [Format] parameter of TimeStamp, you could give round problems, and have a difference of minutes, creating invalid timestamps. Note that if you have hours less than 10, you should use left(...., 15). I recomend that you format these field to HH:MM:SS, or HH:MM and don't use Left.

Then, the Concat creates the complete string with all the max values.

Im agree with you, IT IS POSSIBLE!!

Re: Set analysis Question

sebastiandperei — Sat, 25 Aug 2012 14:28:07 GMT

matan... I taked time in response your question, and also explain you the solution, and you not even mark as answered?

Re: Set analysis Question

Sun, 26 Aug 2012 17:50:15 GMT

Thanks a lot !!!

Somehow i knew it can be done.

Sorry for not comment earlier- i've been on vacation.

Did you know if this solution is easier to calculate then the firstsortedvalue formula ?

Thanks again for your effort

Re: Set analysis Question

sebastiandperei — Sun, 26 Aug 2012 21:02:59 GMT

Its Ok Matan!! Did you went to any vacation place?

The solution with firstsortedvalue is most simply, but i don't know if it's faster to calculate...

You can try both and comment to us!