^@ operator for text
The following documentation comment has been logged on the website:
Page: https://www.postgresql.org/docs/14/functions-string.html
Description:
In the new documentation
https://www.postgresql.org/docs/14/functions-string.html
you again lost information about ^@ operator for text and keep information
about only function starts_with on which this operator is based. But ^@ is
very important, because it can be accelerated by special index SP-GIST
index.
https://www.postgresql.org/docs/14/spgist-builtin-opclasses.html
The task to filter text strings by prefix is rather common and using ^@ and
SP-GIST is the best solution for this (rather options is to use starts_with
without index acceleration or use LIKE construction with SP-GIST, which more
complex (need to mention C locales), overengeniered and may be more slow).
As I say the filtering text by prefix is very common task, but information
about the best method is absent now.
PG Doc comments form <noreply@postgresql.org> writes:
In the new documentation
https://www.postgresql.org/docs/14/functions-string.html
you again lost information about ^@ operator for text and keep information
about only function starts_with on which this operator is based.
"Again"? It was never there before, cf
https://git.postgresql.org/gitweb/?p=postgresql.git&a=commitdiff&h=710d90da1
I did do something about this recently, though:
https://git.postgresql.org/gitweb/?p=postgresql.git&a=commitdiff&h=2ae5d72f0
regards, tom lane
23 дек. 2021 г., в 18:18, Tom Lane <tgl@sss.pgh.pa.us> написал(а):
PG Doc comments form <noreply@postgresql.org> writes:
In the new documentation
https://www.postgresql.org/docs/14/functions-string.html
you again lost information about ^@ operator for text and keep information
about only function starts_with on which this operator is based."Again"? It was never there before, cf
https://git.postgresql.org/gitweb/?p=postgresql.git&a=commitdiff&h=710d90da1
I did do something about this recently, though:
https://git.postgresql.org/gitweb/?p=postgresql.git&a=commitdiff&h=2ae5d72f0
regards, tom lane
I think need to mention that the main benefits of this operator (vs function starts_with) is the using with special SP-GIST index. So searching and filtering can be indexed.
=?utf-8?B?0J7Qu9C10LMg0KHQsNC80L7QudC70L7Qsg==?= <splarv@ya.ru> writes:
23 дек. 2021 г., в 18:18, Tom Lane <tgl@sss.pgh.pa.us> написал(а):
I did do something about this recently, though:
https://git.postgresql.org/gitweb/?p=postgresql.git&a=commitdiff&h=2ae5d72f0
I think need to mention that the main benefits of this operator (vs function starts_with) is the using with special SP-GIST index. So searching and filtering can be indexed.
Not really true anymore, see a148f8bc0.
regards, tom lane