incremental planning and execution (IPE)

Database
Senior Supporter

incremental planning and execution (IPE)

Hi all,

I am exploring the new IPE feature on 14.10. Very nice!

But sometimes the explain is showing

"This request is eligible for incremental planning and execution (IPE)

 but does not meet cost thresholds."

I scaned the documentation but didn't find any further mentioning on this. 

Can someone explain these cost thresholds?

Ulrich 

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3 REPLIES
Junior Contributor

Re: incremental planning and execution (IPE)

Hu Ulrich,

IPE should kick in if it reduces the overall runtime, so this query probably accessed too small tables.

I usually get the same when I try it on a VM :-)

Senior Supporter

Re: incremental planning and execution (IPE)

yes, I used "only" 1 Mio rows on the PPI table.

But the SSI queries also contained a UPI access so should be pretty fast. I was wondering where to draw the line and was therefor asking for more details on these thresholds. 

Once I tried with "big" tables I saw that it was used. Took me some time to find the dynamic explain option - there might be some room for improvement in the documentation - or I was just not able to find a good introduction into this...

Enthusiast

Re: incremental planning and execution (IPE)

Hi,

IPE applies to queries using:

1. Single-row relation

2. Non-correlated scalar sub-queries

Single-row relation points to query condition based on USI or UPI. Which are most likely to be a Tactical queries.

Under limitations, IPE do not process Tactical queries especially if the query has caching plan.

In this scenario, I am trying to understand what type of queries fall into "Single-row relation" which gets benefit out of IPE process.

Thanks!!