topic Data timestamp in QlikView

Data timestamp

Wed, 28 Apr 2010 18:36:23 GMT

I have seen reports with a box showing the data load time and date. Can someone tell me how this is done ?

Thank you.

Data timestamp

johnw — Wed, 28 Apr 2010 18:40:17 GMT

Now(0) is the time of the reload.

Data timestamp

boorgura — Wed, 28 Apr 2010 18:41:54 GMT

You can have a list box with the following expression:

= 'Reloaded at ' & ReloadTime()

Data timestamp

boorgura — Wed, 28 Apr 2010 18:46:45 GMT

John,

I would assume both now(0) and reloadTime() are return the same.

Correct me if I'm wrong.

Data timestamp

Wed, 28 Apr 2010 18:47:24 GMT

Thank you, worked well

Data timestamp

Wed, 28 Apr 2010 18:48:50 GMT

This returned the current date and time, I was looking for the data time and date which I got from another post. Thanks for your input.

Data timestamp

johnw — Wed, 28 Apr 2010 19:21:45 GMT

Neither now(0) nor reloadtime() return the current date and time. They return the time of the reload. So I don't know what you're talking about.

Rocky, I believe they return the same timestamp, yes. In at least my current application, now(0) obeys my default timestamp formatting, and reloadtime() does not, but I'm not sure that means anything. Reloadtime() is probably better simply because what it does is more obvious, and also because QlikView has, in the past, changed what the now() parameters do, thus messing up a lot of our existing applications.

Data timestamp

Wed, 28 Apr 2010 20:09:14 GMT

You are correct, apologies for my error.

Data timestamp

rwunderlich — Wed, 28 Apr 2010 20:42:09 GMT

A note on now(0). When used in the UI, now(0) and ReloadTime() both return the End TIme of the last reload. When used in script, now(0) and ReloadTime() returns the end time of the previous reload. So either will return the End Time of the reload if used in the UI.

If you want to display the Start Time of the reload, which can be more meaningful on a long reload, you have to set your own value in the script. I usuually use:

LET SCRIPT_START = now(1);

as the first line of the script.

(I reliaze the OP was asking about data time, but I wanted to add this clarification about now(0) because I've made the script vs UI mistake in the past.

-Rob

Data timestamp

Thu, 29 Apr 2010 04:32:27 GMT

Inserting the time of the reload may not neccessarily reflect when the data itself was updated. If you are using QVD files, you may want to use a timestamp/ combination of timestamps on the QVD files instead of the time the application was reloaded.

Data timestamp

johnw — Thu, 29 Apr 2010 17:08:34 GMT

I agree with and use the last two suggestions (start of reload, time of QVD). My typical application has an "About" page that includes the start of the reload, and the timestamps of all QVDs (and sometimes other data sources) that were used in the application. It's probably mostly for my own benefit - I doubt users check the about page. So when knowing the currency of the data is more important, I sometimes put the most relevant date or timestamp on every page, and change the font color to red if it is older than would normally be acceptable. Other applications (not my own) even have a pop up to warn users that the data is stale, so that you're CERTAIN they're aware that they shouldn't completely trust the data. We also have procedures in place to alert the QlikView administrators (of which I am one) when reloads fail, and when applications have not been reloaded in a given period of time.

Here's an example of my usual display of the reload information on the About tab:

Data timestamp

Wed, 11 Aug 2010 10:54:53 GMT

How would you build up the table shown above in your QV application ? Do you upload it using variables or is there a way to store the QVDcreatetimes in a table by means of a load command ?

Reason for my asking is that I a have a QV application that consists of aggregated data tah can be reloaded at any time by means of an external event, but also detail data that is only refreshed once a day (because of performance reasons on the operational server on which the data resides).

As we are always reloading our Qlikview applications from QVD files (optimized loads), I want to add a tab in the application where I can actually see for each QVD file what it's last reload time / creation time has been. The Now() or Lastreloadtime() function doesn't mean anything if you are reloading from QVD files, as the timestamp of the QVD file will tell you the timestamp of data shown in the application.

The same applies for the end user using the application. Reloadtime doesn't mean a single thing when using QVD files.

Data timestamp

johnw — Wed, 11 Aug 2010 19:04:25 GMT

You can load the qvdcreatetimes without variables. I've recently started doing it like the script below. Most of our QVDs are in the same place and have usable names, so it can be done pretty simply. If you had QVDs in several different places, and wanted your display names to differ from the QVD names, you could probably do a two-field load, one for the name you wanted to see, and one for the location and name of the QVD.

[Data Source Load Times]:
LOAD
"Data Source"
,evaluate('qvdcreatetime(' & chr(39) & '..\..\server\MasterData\QVD\'
& replace("Data Source",' ','_') & '.qvd' & chr(39) & ')') as "Last Loaded"
INLINE [
Data Source
Address
Bill Of Lading
Catalog
Coil
Customer
Order Acknowledgement Captions
Order Item
Product Type
Tally
Tally Coil
Truck Control
];

Data timestamp

Mon, 03 Oct 2011 16:06:04 GMT

John,

My case is similar to that of Xavier has mentioned. I reload different data tables at different time periods(hourly, daily and monthly). So I have classified my sheets to daily, hourly & monthly catageries(based on tables they use and created qvds for each sheet) and scheduled reload for QVDs.

My master QVW reloads everytime there is a hourly/monthly/daily reload is succesful in server. I have all QVDs sorted into different folders.

Now I want to present the reload time of data on each sheet based on reload time of their QVDs, instead of reload time of master QVW. How do I do that?

please help me with the coding part.

Krishna

Data timestamp

rwunderlich — Tue, 04 Oct 2011 20:30:02 GMT

You can get the "reload time" for any qvd with the function:

QvdCreateTime('path\myfile.qvd')

-Rob