Re: PATCH: CITEXT 2.0

On Jul 7, 2008, at 12:46, Zdenek Kotala wrote:

>> So, the upshot is that the = and <> operators are not locale-aware,  
>> yes? They just do byte comparisons. Is that really the way it  
>> should be? I mean, could there not be strings that are equivalent  
>> but have different bytes?
>
> Correct. The problem is complex. It works fine only for normalized  
> string. But postgres now assume that all utf8 strings are normalized.

I see. So binary equivalence is okay, in that case.

> If you need to implement < <= >= > operators you need to use strcol  
> which take care of locale collation.

Which varstr_cmp() does, I guess. It's what textlt uses, for example.

> See unicode collation algorithm http://www.unicode.org/reports/tr10/

Wow, that looks like a fun read.

Best,

David