[sqlite] xBestIndex() implementation question

2015-05-15 Thread Hick Gunter
Kuang [mailto:jilong.kuang at samsung.com] Gesendet: Donnerstag, 14. Mai 2015 04:05 An: sqlite-users at mailinglists.sqlite.org Betreff: [sqlite] xBestIndex() implementation question Hello, I'm working on a project using SQLite virtual table. Now I have a problem about the implementatio

[sqlite] xBestIndex() implementation question

2015-05-14 Thread Jilong Kuang
...@mailinglists.sqlite.org] On Behalf Of Eric Hill Sent: Wednesday, May 13, 2015 7:46 PM To: General Discussion of SQLite Database Subject: Re: [sqlite] xBestIndex() implementation question I'm just a few days into an xBestIndex/xFilter implementation myself, but my approach is, if I can create

[sqlite] xBestIndex() implementation question

2015-05-14 Thread Eric Hill
I'm just a few days into an xBestIndex/xFilter implementation myself, but my approach is, if I can create the requested index, I set the cost to log(number of rows) of the table, and if I am choosing not to create the requested index, I set the cost to number of rows. I suspect that gives

[sqlite] xBestIndex() implementation question

2015-05-14 Thread Jilong Kuang
Hello, I'm working on a project using SQLite virtual table. Now I have a problem about the implementation of xBestIndex() function, in particular, the estimatedRow and estimatedCost variables. As the aConstraint array does not contain the RHS expression value for each constraint (only iColumn

[sqlite] xBestIndex() implementation question

2015-05-13 Thread Roger Binns
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 05/13/2015 08:06 PM, Jilong Kuang wrote: > Sure, that is one option. But I'm just wondering if inside the > xBestIndex() we can get the value field, we can do a much better > job to give the cardinality info. Note that the value could be something