Обсуждение: Locale vs LIKE

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Locale vs LIKE

От
"Stephen Denne"
Дата:
Given the improvements in 8.3 listed in the release notes:
- Improve efficiency of LIKE/ILIKE, especially for multi-byte character sets like UTF-8 (Andrew, Itagaki Takahiro)

Does this still hold:
http://www.postgresql.org/docs/8.3/interactive/locale.html

"The drawback of using locales other than C or POSIX in PostgreSQL is its performance impact. It slows character
handlingand prevents ordinary indexes from being used by LIKE. For this reason use locales only if you actually need
them."

i.e. Do I still have to either initdb --locale=C or explicitly use text_pattern_ops?

(Queries include predicates of the form [indexed text expression] like "ABC%")

Stephen Denne

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Re: Locale vs LIKE

От
Gregory Stark
Дата:
"Stephen Denne" <Stephen.Denne@datamail.co.nz> writes:

> i.e. Do I still have to either initdb --locale=C or explicitly use
> text_pattern_ops?

yes, if you want an index to be used

--  Gregory Stark EnterpriseDB          http://www.enterprisedb.com Ask me about EnterpriseDB's PostGIS support!