Re: Create duplicate of existing operator
От | Tom Lane |
---|---|
Тема | Re: Create duplicate of existing operator |
Дата | |
Msg-id | 11505.1329449735@sss.pgh.pa.us обсуждение исходный текст |
Ответ на | Create duplicate of existing operator (Andy Chambers <achambers@mcna.net>) |
Список | pgsql-general |
Andy Chambers <achambers@mcna.net> writes: > Is it possible to use CREATE OPERATOR to make "&&" behave like "and"? Hmm ... AND is not really an operator, but a primitive expression construct. So I was about to say "no", but then it occurred to me you could do something like (untested): create function nonstandard_and(bool,bool) returns bool as 'select $1 and $2' language sql; create operator && (procedure = nonstandard_and, leftarg = bool, rightarg = bool); This would be completely unworkable unless the implementation function is an inline-able SQL function, because otherwise the planner will not recognize that your && means AND, resulting in spectacularly bad optimization. But with that, maybe you could get away with it. I would not recommend it though, because you'll be paying through the nose (inlining isn't a remarkably cheap operation) for what fundamentally is gratuitously nonstandard, unportable SQL syntax with no obvious redeeming value. The above hack is a cute hack, but it's just a hack not something I'd recommend for production. regards, tom lane
В списке pgsql-general по дате отправления: