TaskQuery: custom orderBy

[Torsten Geise]

Hi,

Is it possible to perform a TaskQuery.listPage with custom "orderBy"?

We want to order the resulting tasklist by followUpDate (if present) or taskCreateTime (if followUpDate is null).

Thanks,

Torsten

[Matthijs Burke]

Hi Torsten,

Have you seen the TaskQuery javadoc page[1]? There are methods for orderByFollowUpDate [2] and OrderByTaskCreateTime [3].

Does this help you?

Cheers,
Mat

[1]: https://docs.camunda.org/javadoc/camunda-bpm-platform/7.3/org/camunda/bpm/engine/task/TaskQuery.html
[2]: https://docs.camunda.org/javadoc/camunda-bpm-platform/7.3/org/camunda/bpm/engine/task/TaskQuery.html#orderByFollowUpDate%28%29
[3]: https://docs.camunda.org/javadoc/camunda-bpm-platform/7.3/org/camunda/bpm/engine/task/TaskQuery.html#orderByTaskCreateTime%28%29

[Torsten Geise]

Hi Mat,

thanks for the response. I know that I can use these methods in a task query. But I want to make a custom task query and order by followUpDate OR createTime. Something like this:

if followUpDate is not null

  use followUpDate for sorting

else 

  use createTime for sorting

I could imagine writing a custom comparator and set this comparator as orderBy clause in the TaskQuery, e.g. TaskQuery.createTaskQuery().orderBy(myComparator).list.

Best regards,

Torsten

[thorben....@camunda.com]

Hi Torsten,

You could write a native task query [1]. Sorting is implemented in the SQL query, not in Java. Sorting the query results on the application-side is not practicable when result pagination is used. Combining two orderings in the way you describe could be solved in the query by generating a temporary column with the desired dates and ordering over that. However, this is not doable with API.

Cheers,
Thorben

[1] https://docs.camunda.org/manual/7.3/guides/user-guide/#process-engine-process-engine-api-native-queries