Re: Documentation on the use of triggers

[Steve Yurong Su]

Hi Ning,

Thanks for your contribution! The PR looks good to me, I have merged it.

Steve Su

苏志 <273670...@qq.com.invalid> 于2022年5月1日周日 23:23写道：
>
> The following shows the SQL syntax of registering a trigger.
>
> CREATE TRIGGER <TRIGGER-NAME&gt;
> (BEFORE | AFTER) INSERT ON <FULL-PATH&gt; AS <CLASSNAME&gt; WITH (   
> <KEY-1&gt;=<VALUE-1&gt;,    <KEY-2&gt;=<VALUE-2&gt;,    ... )TRIGGER-NAME is 
> a globally unique ID of the trigger, which is case sensitive. At present, the 
> trigger can listen to all data insertion operations on the time series. The 
> hook can be called BEFORE or AFTER the data is inserted. FULL-PATH can be a 
> time-series (measurement) path such as root.sg1.d1.s1, a device path such as 
> root.sg1.d1, a storage group path such as root.sg1, or even a non-measurement 
> path with business semantic such as root.sg1.x. CLASSNAME is the full class 
> name of the trigger. Note
> CLASSNAME, KEY and VALUE in the attributes need to be quoted in single or 
> double quotes.
>
> Only one trigger can be registered per full-path.
>
> When multiple prefix paths of a path are registered with triggers, for 
> example, trigger trigger-sg1d1s1 is registed on root.sg1.d1, trigger 
> trigger-sg1d1 is registed on root.sg1.d1, and trigger trigger-sg1 is registed 
> on root.sg1. When inserting data to root.sg1.d1.s1, triggers will be 
> triggered in the following order: trigger-sg1d1s1 -&gt; trigger-sg1d1 -&gt; 
> trigger-sg1.
>
> Best,
> ------------------------------------
> gongning