When a self-reference appears within the FROM clause of the recursive subquery, the reference to the recursive table cannot appear on the null-supplying side of an outer join.是什么意思_When a self-reference appears within the FROM clause of the recursive subquery, the reference to the recursive table cannot appear on the null-supplying side of an outer join.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句