topic Re: Conditional DQL statements based on value of input variable in DQL

Conditional DQL statements based on value of input variable

HeadScratcher — Fri, 20 Sep 2024 07:45:36 GMT

I have some DQL that presents a table of data of web service calls. The data can be examined in different ways e.g. by consumer_id or application_name etc. To achieve this I either have to edit query each time or create multiple tables on a dashboard.

How can I avoid this? Can I create an input variable called Choice (holding different DQL text) and then use that to visualise the data from different views?

// Summarise the output... | summarize hit_count = count(),by:{ $Choice, response_out_http_code }

When I used the above the $Choice resolves to the string "consumer_id" but the DQL is treating it as a string literal and not actually using it in the query.

What am I doing wrong?

Re: Conditional DQL statements based on value of input variable

krzysztof_hoja — Fri, 20 Sep 2024 09:59:06 GMT

variables are always strings and are treated as literals in DQL query. They cannot be used as a field names, commands or function names. The workaround is possible using this trick:

data record(a=1, b="a"), record(a=1, b="a"), record(a=2, b="b"), record(a=2, b="b"), record(a=2, b="b"), record(a=3, b="c"), record(a=3, b="d"), record(a=3, b="e"), record(a=3, b="e"), record(a=4, b="e") | fieldsAdd split=coalesce( if($splitField=="a", a), if($splitField=="b", b) ) | summarize cnt=count(), by: { split }

depending on variable value, proper field value will be kept under added filed of the same name independent from the choice. Now it can be directly used in a query (in by: {}).

Kris

Re: Conditional DQL statements based on value of input variable

HeadScratcher — Fri, 20 Sep 2024 13:20:06 GMT

I thought there must be a way. That is a pretty neat solution and actually helps tidy up my DQL a little bit too.

Re: Conditional DQL statements based on value of input variable

almog42 — Sun, 04 May 2025 15:31:30 GMT

Heyy

now you can use variables not as a string literal by adding the :noquote to the variable name for example:

// for refrence writing the variable value $Problam_Columns = "event.kind" fetch dt.davis.problems | limit 1 | fields $Problam_Columns:noquote // the "code" that will be used fetch dt.davis.problems | limit 1 | fields event.kind

also here is the link for the docs for that:

https://docs.dynatrace.com/docs/analyze-explore-automate/dashboards-and-notebooks/dashboards-new/components/dashboard-component-variable#dollarvarname-noquote