* motivation: remove recursive procession of AND/OR list (hangs with 10062 and more subexpressions)
* patch is short, clean and respect postgresql source code requirements * patch was applied cleanly without warnings * all regression tests was passed * I successfully evaluated expression with 100000 subexpressions * there is no significant slowdown
possible improvements
a = (A_Expr*) list_nth(pending, 0);
a = (A_Expr*) linitial(pending);
not well comment
should be -- "If the right branch is also an SAME condition, append it to the"
+ /* + * If the right branch is also an AND condition, append it to the + * pending list, to be processed later. This allows us to walk even + * bushy trees, not just left-deep trees. + */ + if (IsA(a->rexpr, A_Expr) && ((A_Expr*)a->rexpr)->kind == root_kind) + { + pending = lappend(pending, a->rexpr); + } + else + { + expr = transformExprRecurse(pstate, a->rexpr); + expr = coerce_to_boolean(pstate, expr, root_kind == AEXPR_AND ? "AND" : "OR"); + exprs = lcons(expr, exprs); + }
I don't see any other issues, so after fixing comments this patch is ready for commit
