Re: No Row Chaining "Bug" ?

Not for sure where the 999 comes from but take a look at bug #9373758 and the following parameter added in 11.2.0.4.4 and 12???? This appears to work for inserts, although subsequent updates seem to still become multiple row pieces.

"_rowlen_for_chaining_threshold"

I posted the below to this list in Jan.

"
I can’t believe I’ve put this off since April, although not a coincidence that my company was acquired in May.

I was finally able to test the hidden parameter and it works ( mostly ). I used imp, trying to keep it simple, to load 100k rows that were plagued with populated column ID’s > 255. With the parameter set to 0, simulating pre-parameter, the data loaded with 3,420 chained rows. After setting the parameter to 8000, with a 8k block size database, I reloaded the data and although I expected the chained rows to be 0 it left 29. I have yet to explain the 29 since they are not too large to fit in a block, average row size of 852, and were less than the 8000 I set the parameter to. After a CTAS of the previously loaded table the new resulting table with the same 100k rows returned 0 chained rows. I ran the load process a number of times consistently with the same results.

Nonetheless, although not perfect it seems to make a significant dent in the number of inter block chained rows and after some additional testing we will be excited to get this into production. If I can find some time to dig deeper in this I’ll try to dump the block and see what is going on.

In case you were wondering, here is the parameter. _rowlen_for_chaining_threshold

Thanks again Gaja for pointing out the bug ( way back in April ) "

> On May 20, 2015, at 4:57 AM, Chitale, Hemant K <Hemant-K.Chitale_at_sc.com> wrote:
>
> Anyone know what this Bug is :
> Bug 20901134 : A ROW WITH 999 COLUMNS WILL NOT CAUSE 'ROW CHAINED' IN 12C
>
> There’s no text in the bug.
>
> Hemant K Chitale
> Senior Product Specialist
> Finance&Risk Product Engineering
>
> Standard Chartered Bank
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> Singapore 486028
>
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> Email : Hemant-K.Chitale_at_sc.com <mailto:Hemant-K.Chitale_at_sc.com>
> Fonenet : 652-63127
>
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>
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