Skip to Content

Hana SQL Query on composite provider ends with OOM


Our BW team reported issue on following query which results in OOM.

Select top 1000 * from "ZSALES_MART_5642"."SWEDEN::C_SORD_INT99";

From the OOM file we can see allocator "Pool/JoinEvaluator/JERequestedAttributes/Results" is taking almost 100GB of memory. Though underlying tables for above query are very small like 25MB and 7MB.

So I'm not sure why joins on those 2 tables and few other can consume 100GB and still fails.

Please bear with me my little knowledge on sql side.

Attached screenshot of Visualiser Planvisplan.png

.. couldn't upload the full plan as it's not allowed.

Looking forward to gain some ideas from your expertise!!


visplan.png (44.6 kB)
Add a comment
10|10000 characters needed characters exceeded

Assigned Tags

Related questions

1 Answer

  • Posted on Jul 27, 2020 at 12:17 PM

    - Take a look at how this view/cp is created and if there are any performance bottlenecks in them which is why its causing this issue

    - How many columns are you querying and why select *? this to me dosent look like an ideal query. You could try to query only those columns that you need and check if its still bad

    - Do backtracking to identify the exact performance bottleneck, do this either bottom to top or vice versa by running the query on the supporting tables/views projection nodes from top/bottom


    Abhishek Shanbhogue

    Add a comment
    10|10000 characters needed characters exceeded

Before answering

You should only submit an answer when you are proposing a solution to the poster's problem. If you want the poster to clarify the question or provide more information, please leave a comment instead, requesting additional details. When answering, please include specifics, such as step-by-step instructions, context for the solution, and links to useful resources. Also, please make sure that you answer complies with our Rules of Engagement.
You must be Logged in to submit an answer.

Up to 10 attachments (including images) can be used with a maximum of 1.0 MB each and 10.5 MB total.