Re: Fuzzy substring searching with the pg_trgm extension

On 29.01.2016 17:15, Teodor Sigaev wrote:
>> The behavior of this function is surprising to me.
>>
>> select substring_similarity('dog' ,  'hotdogpound') ;
>>
>>   substring_similarity
>> ----------------------
>>                   0.25
>>
> Substring search was desined to search similar word in string:
> contrib_regression=# select substring_similarity('dog' ,  'hot dogpound') ;
>   substring_similarity
> ----------------------
>                   0.75
>
> contrib_regression=# select substring_similarity('dog' ,  'hot dog
> pound') ;
>   substring_similarity
> ----------------------
>                      1
> It seems to me that users search words in long string. But I'm agree
> that more detailed explanation needed and, may be, we need to change
> feature name to fuzzywordsearch or something else, I can't imagine how.
>

Thank you for the review. I will rename the function name. Maybe to 
subword_similarity()?

>
>>
>> Also, should we have a function which indicates the position in the
>> 2nd string at which the most similar match to the 1st argument occurs?
>>
>> select substring_similarity_pos('dog' ,  'hotdogpound') ;
>>
>> answering: 4
> Interesting, I think, it will be useful in some cases.
>
>>
>> We could call them <<-> and <->> , where the first corresponds to <%
>> and the second to %>
> Agree

I will add them.

-- 
Artur Zakirov
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