Shulou(Shulou.com)06/02 Report--

Overview:

The expressions in triggers are very flexible, and we can create a complex logical test monitor in the form of trigger expressions:

{:. ()} {Host: key. Function (parameter)} constant

Functions function: the trigger functions can refer to the retrieved value, current time, or other elements. For a complete list of function supported by trigger expressions, click the official website address supported functions

Function parameter-most numeric functions can use seconds as a parameter. You can use the prefix "#" to indicate that it has a different meaning

FUNCTION CALL describes the sum of sum (600) 600s and the sum of the last five values of sum (# 5)

The last function will get different values with different parameters, and # 2 represents the second-to-last new data. From the old to the latest, the value is 1, 2, 3, 4, 5, 6, 7, 8, 8, 9, 10, last (# 2), the value is 9, and the value is 2. The last function must contain parameters.

The AVG,count,last,min and max functions also support additional parameters, the parameter time_shift (time offset) in seconds. For example, avg (1 hour and 1 day), then you will get the average data within 1 hour yesterday.

[warning] Note: trigger expressions need to be evaluated using history historical data. If history is not available (the time_shift time offset parameter cannot be used), history records must be kept for a long time, at least the records needed. [/ warning]

Trigger expressions can use unit symbols instead of large numbers, such as 5m instead of 300m, or 1d instead of 864001k instead of 1024 bytes, and so on. Operator:

Priority operation definition 1 / divided by 2 * multiplied by 3-minus 4 + plus 5=B+0.000001) does not equal. The usage is as follows:

Axib ⇔ (A=B+0.000001) 8 = equals. The usage of T is as follows:

Amib ⇔ (A > Bink 0.000001) & (A

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