Text operators "~<=~ ~<~ ~>=~ ~>~" not documented

Hello,

While reading [1] I notice $subject operators lacks of explanation in
documentation.


They where introduced in this commit :

commit 2c0556068fc308ed9cce06c85de7e42305d34b86
Author: Peter Eisentraut <peter_e@gmx.net>
Date:   Thu May 15 15:50:21 2003 +0000

    Indexing support for pattern matching operations via separate operator
    class when lc_collate is not C

Comment from this commit :

/*
 * The following operators support character-by-character comparison
 * of text data types, to allow building indexes suitable for LIKE
 * clauses.
 */



So if I understand correctly :


~<~     less than
~>~     greater than
~<=~     less than or equal to
~>=~     greater than or equal to

For all, it is a character-by-character comparison regardless of collation. We
encounter them when we use text_pattern_ops for example :

create index ON users  ( location text_pattern_ops);
explain select * from users where location like 'test%';
                                     QUERY PLAN
------------------------------------------------------------------------------------
 Index Scan using users_location_idx1 on users  (cost=0.43..2.46 rows=54 width=201)
   Index Cond: ((location ~>=~ 'test'::text) AND (location ~<~ 'tesu'::text))
   Filter: (location ~~ 'test%'::text)
(3 lignes)


Should we add them on this page?
https://www.postgresql.org/docs/devel/static/functions-string.html

Thanks!


1: https://www.postgresql.org/docs/current/static/spgist-builtin-opclasses.html


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Adrien NAYRAT

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