On Mon, May 19, 2025 at 10:38:19AM -0500, Nico Williams wrote: > On Mon, May 19, 2025 at 01:25:00PM +0300, Aleksander Alekseev wrote: > > I agree this would be most convenient for the user. Unfortunately this > > will require us to check every SELECT query: "oh, isn't it by any > > chance ORDER BY random() LIMIT x?". I don't think we can't afford such > > a performance degradation, even a small one, for an arguably rare > > case. > > Can the detection of such queries be done by the yacc/bison parser > grammar?
Maybe the `sortby` rule could check if the expression is `random()`, then `sort_clause` could check if `$3` is a one-item `sortby_list` of just `random()` and mark `$$` as special -- this should be cheap, yes? We'd still need to check for `LIMIT` somewhere else.
