On Fri, Sep 21, 2018 at 10:09 AM Pavel Stehule <pavel.stehule@gmail.com> wrote:Hican we implement prefix function for fast test if substr is prefix of some string?create or replace function prefix(str text, substr text)returns boolean as $$ select substr(str, 1, length(substr)) = substr$$ language sql;This function can be very effective in C language. Now it should be implemented with like or regexp, what is significantly more expensive.These would just be wrappers around already existing internal functions, right?
Hican we implement prefix function for fast test if substr is prefix of some string?create or replace function prefix(str text, substr text)returns boolean as $$ select substr(str, 1, length(substr)) = substr$$ language sql;This function can be very effective in C language. Now it should be implemented with like or regexp, what is significantly more expensive.
RegardsPavel-- Best Regards,Chris TraversHead of DatabaseTel: +49 162 9037 210 | Skype: einhverfr | www.adjust.com Saarbrücker Straße 37a, 10405 Berlin
RegardsPavel
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