> Many of those collation problems seem to relate to unicode_ci and > unicode_ci_ai, > and this relates to the usage of ICU functions. > > FB seems to set collation strength properly only where it relates to unique > index. > Otherwise the strength is left default, i.e. equivalent of collate unicode, > for unicode_ci and unicode_ci_ai. > This is my guess after tested and observed many cases. > > If a sorting was ordered by a single column with collate UNICODE, > the result could be shared with collate UNICODE_CI or UNICODE_CI_AI. > But when it comes to ordering by multiple columns, it should be a different > story. > > Is there anyone who can check the relating source code? > ICU's collation strength must be set as follows to make sort key according to > the field's collate property: > default(unicode), primary(unicode_ci_ai) or secondary(unicode_ci)
Feel free to discuss it at fb-devel mailing list (https://sourceforge.net/projects/firebird/lists/firebird-devel) Regards, Vlad
