Hi, Dominique and Steve,

If your long list of ORs are most related to a single column (or a
small number of columns), then it is possible to convert them into an
expression of the form

column_name IN (list_of_strings_or_numbers )

The list in the parentheses has to be either a list of numbers of a
list of strings (a mixture will be treated as a list of strings).

Hope this helps.

John

PS: more information about expressions of a where clause is available at

http://lbl.gov/~kwu/fastbit/doc/html/classibis_1_1whereClause.html


On 9/5/13 3:39 PM, Prunier, Dominique wrote:
> Steve,
> 
>  
> 
> We faced the same issue and we worked around that by carefully
> balancing the big OR with parenthesis so that you don’t go deeper that
> log2(OR count).
> 
>  
> 
> Hope this helps !
> 
>  
> 
> Thanks,
> 
>  
> 
> *From:*[email protected]
> [mailto:[email protected]] *On Behalf Of *Enns, Steven
> *Sent:* Thursday, September 05, 2013 6:16 PM
> *To:* FastBit Users
> *Subject:* [FastBit-users] stack overflow on large queries
> 
>  
> 
> Hi John,
> 
>  
> 
> I am running a query of 2140 OR clauses and observing segmentation
> fault in ibis::qExpr::simplify(ibis::qExpr*&) at recursive depth of
> 1087.  Could you help us debug this?
> 
>  
> 
> Thanks!
> 
> Steve
> 
>  
> 
>  
> 
>  
> 
> 
> 
> _______________________________________________
> FastBit-users mailing list
> [email protected]
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> 
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