Re: Support new path pattern: 0 or more layers

[Eric Pai]

I think we may meet the requirements of matching 0-1 level in the future, then 
*** may be not a good design.
As a single * stands for exactly 1 level now, we can define *{start, end} to 
[start, end) levels, {x} to exactly x levels and {*} to arbitrary levels, where 
** is just a short representation of *{*}.
So it's easy to represent 0 or more layers using *{0, *}.

在 2022/6/21 14:44，“Xiangdong Huang”<saint...@gmail.com> 写入:

    Hi,

    - if only for 0 or more layers, I opt for ***
    - if we want to define a clear range of layers, I opt for *{start, end} or
    **{start, end}

    -----------------------------------
    Xiangdong Huang
    School of Software, Tsinghua University

     黄向东
    清华大学 软件学院


    guoguan...@qq.com.INVALID <guoguan...@qq.com.invalid> 于2022年6月21日周二 10:14写道：

    > Hi guys!
    >      Now IoTDB supports the following path patterns:
    > * (1 asterisk) - one layer
    > ** (2 asterisks) - one or more layers
    >
    >    We need to support a new path pattern: 0 or one or more layers, there
    > are some optional schemes:
    >        Scheme 1, support it directly with a specific syntax:
    >           *** (3 asterisks) -  0 or one or more layers
    >
    >        Scheme 2, use more common syntax:
    >  a special symbol (such as $, or someone else) - 0 or 1 layer
    > $* - 0 or 1 or more layers
    >
    >      JIRA:   
https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fissues.apache.org%2Fjira%2Fbrowse%2FIOTDB-3450&amp;data=05%7C01%7C%7Ccbc22404c72843af731208da53518d0d%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637913906992358086%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=aiZyCx7gbDsIaiVP37%2BB6vc3s6kymBDiw%2FqmdB3igLQ%3D&amp;reserved=0
    >
    >     Any ideas?
    >
    >
    >
    > guoguan...@qq.com
    >