bug: SQLOpenStatement is subclass of SQLStatement, so hiding.

[XenoAmess]

No description provided.

[zrlw]

这个PR有问题吧，

        else if ((parent instanceof SQLStatement
                && !(parent instanceof OracleForStatement))
                || (parent instanceof SQLSelectItem
                && (parent.getParent() instanceof SQLPivot || parent.getParent() instanceof SQLUnpivot))
        ) {
             《== 这个分支处理非OracleForStatement、SQLPivot 、SQLUnpivot，应当在SQLOpenStatement分支前执行
        } else if (parent instanceof SQLOpenStatement) {
            visit(subQuery);
        }