Aleksey Karyakin wrote:

>"
>
>
>If all
>
>
>>indexes are based on UTF-8, the character set used by the client
>>
>>
>doesn't
>
>
>>come into the equation at all.
>>
>>
>
>I'm afraid no. What about case-insensitive, accent-insensitive, etc
>comparisons which are all language-specific?
>
>

Of course they're language specific. But the the collations can be
written to operator on UTF-8 as well (or better) than a language
specific character set.

>There actually are case-insensitive collations in current codebase
>but I would prefer the other way to handle this. Let a collation
>defines multi-level key strings to use in indexes and comparisons and
>an operation itself specifies if it wish to skip any of secondary
>weights. So CASE-INSENSITIVE, etc would be an attribute of
>index/operation not of a collation. Thus we end up with significatnt
>less number of collations preserving vide range of comparison options.
>
>

I think the question of case-insensitivity is an interesting case. In
general, collation is only necessary for a high/low test -- sorting and
range retrievals, while equality can be based on raw byte comparison.
To support case insensitivity, collation is required to determine even
equality.

Are there other collations where equality is collation specific?


--

Jim Starkey
Netfrastructure, Inc.
978 526-1376