HANA Memory Consumption JOIN_SIMPLIFICATION

[arshad_maac]

Hello Experts,

I am observing tremendous reduction in memory consumption in one of my sales report build using HANA SQL. When I use the HINT NO_JOIN_SIMPLIFICATION, I observed the execution plan and I found the the inner join which we do at final step is performed at lower level itself.

As there is a higher reduction in number of records at lower level because of this Inner join, memory consumption is going down as there are lesser number of records for the subsequent operations.

Any Idea how can we achieve this without HINTs, why actually this scenario is occurring ? SAP HANA should be considering best execution plan by itself.

[markmumy]

What does the query execution time look like with and without the hint? It is possible that we are sacrificing memory for better performance.

Mark

[arshad_maac]

Thanks for your response Mark

With Hint it is consuming 1.4 Min only and without it consumes 4 Min. We are more worried about the memory as the memory consumption is going beyond the threshold and getting failed due to expensive query.