[Pgbigm-hackers] Adding similarity() and similarity_op(), '%' to pg_bigm

Back to archive index

Fujii Masao masao****@gmail*****
2013年 10月 3日 (木) 19:55:30 JST


On Thu, Oct 3, 2013 at 7:34 PM, Amit Langote <amitl****@gmail*****> wrote:
> On Thu, Oct 3, 2013 at 7:28 PM, Fujii Masao <masao****@gmail*****> wrote:
>> On Thu, Oct 3, 2013 at 5:52 PM, Amit Langote <amitl****@gmail*****> wrote:
>>> On Thu, Oct 3, 2013 at 5:41 PM, Fujii Masao <masao****@gmail*****> wrote:
>>>
>>>>> So the way to make similarity function case-insensitive would be to change
>>>>> generate_bigm and not the similarity code itself. Also, the change will make
>>>>> the show_bigm function behave differently.
>>>>
>>>> Yes, generate_bigm would need to be updated to make bigm_similarity
>>>> case-sensitive.
>>>>
>>>> *From a user point of view*, bigm_similarity() and upcoming similarity
>>>> search should be case-sensitive? If yes, we should change generate_bigm,
>>>> but its change must not affect the behavior of the full-text search at all.
>>>>
>>>> Or we should just implement both case-sensitive and -insensitive
>>>> bigm_similarity() and similarity search?
>>>>
>>>> Thought?
>>>
>>> Could we say that case-sensitivity applies more to the comparison
>>> functions as in strcmp() vs strcmpi() than similarity() function? What
>>> do you think?
>>
>> It depends the whole design of the full-text (similarity) search, I think.
>> For example, pg_trgm's comparison function is case-*sensitive*.
>> Its generate_trgm function is case-*insensitive*.
>>
>
> How about make generate_bigm() accept a case sensitivity parameter?

Yep, I had the same idea.

> We could make some parts case-sensitive (text matching) while other
> parts case-insensitive (similarity())?

On the second thought, I'm afraid that this means that we need to build
two kinds (case-sensitive and -insensitive) of GIN indexes when we'd
like to use both text-matching and similarity search.

Regards,

-- 
Fujii Masao




Pgbigm-hackers メーリングリストの案内
Back to archive index