evalc

Evaluates the expression on the right, and then assigns a new query parameter or replaces the value of an old query parameter.

Syntax

evalc VAR_NAME=EXPR
Required Parameters
VAR=EXPR
Query parameter. Assign the parameter name on the left side and any combination of expressions that can be evaluated as a value to the right. The value obtained by evaluating the expression is assigned to the query parameter. Unlike the set command, it evaluates all the data at the time the query is executed.

Usage

Set the alert query parameter to true if count exceeds the threshold

evalc alert = if(count > 100000, true, $("alert"))

All input data are assigned after being evaluated with the right side expression, so if its count does not exceed the threshold, use the $() function to re-assign the existing variable value as it is.