postgresql - Do text_pattern_ops comparators understand UTF-8? -


according postgresql 9.2 documentation, if using locale other c locale (en_us.utf-8 in case), btree indexes on text columns supporting queries 

select * my_table text_col 'abcd%'

need created using text_pattern_ops so

create index my_idx on my_table (text_col text_pattern_ops)

now section 11.9 of documentation states results in "character character" comparison. these (non-wide) c characters or comparison understand utf-8?

good question, i'm not totally sure tentative understanding is:

here postgresql means "real characters" (eventually multibyte), not bytes. comparison "understands utf-8" always, or without special index.

the point that, locales have special (non c) collation rules, want follow rules (and call respective locale libraries) when doing comparisons ( <, >...) , sorting. don't want use collations posix regular matching , patterns. hence existence of 2 different types of indexes text.


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