Обсуждение: Does LC_CTYPE affect performance, index use?
I've read that setting LC_COLLATE to something other than "C" / "POSIX" negatively affects performance, and disables use of indexes for LIKE, etc...
Does the same apply to LC_CTYPE?
I am considering setting LC_COLLATE = "C", and LC_CTYPE = "en_US.UTF-8", and using LOWER() to case-fold strings for sorting, and equality. The motivation for setting LC_CTYPE = "en_US.UTF-8", instead of "C", is to gain at least some degree of case-folding for international characters.
Does this sound like a reasonable plan?
Thanks,
Steven Dodd | Software Developer | Street Contxt
416-596-9011 | 19 Mercer St, Suite 301, Toronto, ON, M5V 1H2
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On Wed, 2013-11-20 at 14:57 -0500, Steven Dodd wrote: > I've read that setting LC_COLLATE to something other than "C" / > "POSIX" negatively affects performance, and disables use of indexes > for LIKE, etc... It doesn't disable the use of indexes, you just need to create different indexes. > Does the same apply to LC_CTYPE? Yes. > I am considering setting LC_COLLATE = "C", and LC_CTYPE = > "en_US.UTF-8", and using LOWER() to case-fold strings for sorting, and > equality. The motivation for setting LC_CTYPE = "en_US.UTF-8", instead > of "C", is to gain at least some degree of case-folding for > international characters. > Does this sound like a reasonable plan? No, if you need internalized behavior, then set both LC_COLLATE and LC_CTYPE to en_US.UTF-8 (or some other suitable locale) and check the relevant documentation sections about how to create the right indexes.