topic Re: How to refernce a $Variable if the returned output is a Table in Dashboarding

How to refernce a $Variable if the returned output is a Table

AlanFoley — Wed, 18 Feb 2026 07:41:18 GMT

Hi Guys

These are a couple of Visuals I have in an Availability Dashboard (refer to attached image)

Description of visuals referenced by numbers

1 – DQL query – Host availability per Application and Host - Visual = Table

2 – Same DQL query as in (1) with the addition of a summarize/ avg calculation (by Application)

| summarize {avg(Availability_BH),avg(Availability_NBH)}, by:{$Application}

3 – Hosts - Same DQL query as in (1) with the addition of a summarize / count (by Host)

| summarize Hosts = countDistinct(host.entity.name)

3 – Applications - Same DQL query as in (1) with the addition of a summarize / count (by Applications)

| summarize Applications = countDistinct(Application)

This scenario works fine but it is not efficient from a DQL query perspective as it needs to be run 5 times, once for the Detail (1) and then again for the remaining visuals(2,3) based on what summarization needs to take place depending on the Visual used

What I want to be able to do is perform the DQL query only once and then reference it in the other visual and then perform the required summarization

This could be possible by defining a hidden Variable called “HostDetail” and running the detail DQL query here which will contain the output in Table format as per (1) – I could then reference it and do the summarization

If the $HostDetail was JSON referencing it will be quite straightforward as it would be done as follows:

data json:$HostDetail

However because it is a Table I am not sure how to reference $HostDetail, I have referred to the DQL reference and tried a number of DQL functions but have been unsuccessful as I am not sure which function to use

Basically i am looking for this kind of syntax

data ??????($HostDetail)

Is it possible? Looking for help with DQL syntax to use in this scenario

Why I want to get this working:

A single DQL query to maintain
Cost saving as the DQL query only needs to run once and then referenced in a $Variable based on summarization preference
More efficient

Appreciate the assistance
Thanks

Alan

Re: How to refernce a $Variable if the returned output is a Table

AlanFoley — Thu, 19 Feb 2026 09:33:30 GMT

Just an update

I have made some progress on this - what I do at the end of the DQL now is to convert the Table into a JSON array as follows:

| fieldsAdd row = record(Field1=Field1,Field2=Field2 ,Field3=Field3)

| summarize all_rows = collectArray(row)

The data is returned in JSON format (Validated by an online JSON validator) - see sample data below

However referencing the variable as follows does still not work

data json:$HostDetail

I get this error msg so it does seem as if the format may not be seen as JSON but it is
The command `data` parameter `json` value is invalid: the value needs to be a JSON object or JSON array of JSON objects. Please specify a valid parameter and try again.

Here is a sample of the returned JSON

[{"MonthId":"202602","host.id":"HOST-318A276BB0F116E1","host.entity.name":"Server1","Cloud_or_OnPremises":"Cloud","osArchitecture":"X86","osType":"WINDOWS","Hypervisor":"HYPER_V","Environment":"QA","Hours_BH":"59","Availability_BH":98.44632768361582,"Availability_BH_w10":9.844632768361583,"Hours_NBH":"79","Availability_NBH":95.61181434599156,"Availability_NBH_w5":4.780590717299578,"HoursInMonth":"138","Hours_Check_MustBeZero":"0","Application":"Application 1"},{"MonthId":"202602","host.id":"HOST-45D773ABF8B98F74","host.entity.name":"Server2","Cloud_or_OnPremises":"OnPremises","osArchitecture":"X86","osType":"WINDOWS","Hypervisor":"VMWARE","Environment":"PROD","Hours_BH":"61","Availability_BH":98.87978142076503,"Availability_BH_w10":9.887978142076504,"Hours_NBH":"108","Availability_NBH":100,"Availability_NBH_w5":5,"HoursInMonth":"169","Hours_Check_MustBeZero":"0","Application":"Application 1"}]

I would appreciate any insights

Thanks

Alan

Re: How to refernce a $Variable if the returned output is a Table

AlanFoley — Thu, 19 Feb 2026 09:41:05 GMT

I forgot to add that i also tested in notebook as follows and data was returened sucessfully

data json:"""
[{"MonthId":"202602","host.id":"HOST-318A276BB0F116E1","host.entity.name":"Server1","Cloud_or_OnPremises":"Cloud","osArchitecture":"X86","osType":"WINDOWS","Hypervisor":"HYPER_V","Environment":"QA","Hours_BH":"59","Availability_BH":98.44632768361582,"Availability_BH_w10":9.844632768361583,"Hours_NBH":"79","Availability_NBH":95.61181434599156,"Availability_NBH_w5":4.780590717299578,"HoursInMonth":"138","Hours_Check_MustBeZero":"0","Application":"Application 1"},{"MonthId":"202602","host.id":"HOST-45D773ABF8B98F74","host.entity.name":"Server2","Cloud_or_OnPremises":"OnPremises","osArchitecture":"X86","osType":"WINDOWS","Hypervisor":"VMWARE","Environment":"PROD","Hours_BH":"61","Availability_BH":98.87978142076503,"Availability_BH_w10":9.887978142076504,"Hours_NBH":"108","Availability_NBH":100,"Availability_NBH_w5":5,"HoursInMonth":"169","Hours_Check_MustBeZero":"0","Application":"Application 1"}]
"""

So looks more like an issue accessing the $Variable in Dashboards