Re: Row pattern recognition

> On Fri, Sep 22, 2023, 3:13 AM Tatsuo Ishii <ishii(at)sraoss(dot)co(dot)jp> wrote:
>
>> > Op 9/22/23 om 07:16 schreef Tatsuo Ishii:
>> >>> Attached is the fix against v6 patch. I will include this in upcoming
>> >>> v7 patch.
>> >> Attached is the v7 patch. It includes the fix mentioned above. Also
>> > (Champion's address bounced; removed)
>>
>> On my side his adress bounced too:-<
>>
>
> Yep. I'm still here, just lurking for now. It'll take a little time for me
> to get back to this thread, as my schedule has changed significantly. :D

Hope you get back soon...

By the way, I was thinking about eliminating recusrive calls in
pattern matching. Attached is the first cut of the implementation. In
the attached v8 patch:

- No recursive calls anymore. search_str_set_recurse was removed.

- Instead it generates all possible pattern variable name initial
strings before pattern matching. Suppose we have "ab" (row 0) and
"ac" (row 1). "a" and "b" represents the pattern variable names
which are evaluated to true. In this case it will generate "aa",
"ac", "ba" and "bc" and they are examined by do_pattern_match one by
one, which performs pattern matching.

- To implement this, an infrastructure string_set* are created. They
take care of set of StringInfo.

I found that the previous implementation did not search all possible
cases. I believe the bug is fixed in v8.

Best reagards,
--
Tatsuo Ishii
SRA OSS LLC
English: http://www.sraoss.co.jp/index_en/
Japanese:http://www.sraoss.co.jp