I have a field in a webmap called 'deviceId' that displays a unique string for each device that pushes data into it.
Ideally, I want a widget in an Operations Dashboard that displays a count of the number of unique devices.
I can see how to display a count of features, but can't see how to create a query that filters by unique value.
In a round-a-bout way, a bar graph achieves something similar, by displaying a unique bar for each deviceId with counts of the number of features for that deviceId, but it's not the effect I want. I just need a single count figure.
You could start by using the Query widget to help identify any unique devices and then create a counter that takes the query results and displays them according to count per unique device in a summary widget . I hope it works for you.
My suggestion is the as follows:
First Create a query widget and insert a query by atribute.
Then create a resumen widget. In the source dataset shoose the results of the query widget.
When you execute a query, the resume widget shows the count given the query.
Thanks for replying.
I might not be explaining myself properly though. Take the following sample table data:
objectid | deviceId
1 | ABCDEFG
2 | ABCDEFG
3 | ABCDEFG
4 | ZYXWVUT
You can see that there are four records, but three have the same deviceid. I want the summary count to report the count as '2', because there are two unique deviceid's in the table.
I understand the 'summary' (resume in Spanish?? ) widget, but cannot see any way, using the standard query tools that are available, to create a query that returns unique values.
The equivalent SQL query would be something like: 'SELECT DISTINCT deviceId from.....' .
I don't think it can be done using the standard tools, but still hoping someone might suggest a way so we don't have to custom write something...!
Just to check did you find the solution to the above ? I am also stuck on the same issues, and any help from you will be appreciated.
Ok , thanks for the information.
Thanks and Regards,
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