Incorrect Syntax for Custom Property in IF Statement
why this syntax is incorrect for a custom property? IF( “utm_source=” NOT in Current URL,UNDEFINED,utm_source)
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There are several issues with your custom property formula syntax in Mixpanel: 1. The
inoperator is being used incorrectly. In Mixpanel's custom property formulas, theinoperator checks if a value is contained within another value or list, but your syntax has it reversed. The correct syntax would be to check if a value is in a string, not if a string contains a value.2. TheNOTkeyword is incorrectly placed. In Mixpanel, you should use thenotfunction or simply use thenot inoperator.3. "Current URL" is not a valid reference in Mixpanel custom properties. You would need to use an actual property that contains the URL, such as$current_url.4. "UNDEFINED" should be lowercaseundefinedor you can simply omit the value to get an undefined result.Based on the Mixpanel documentation on custom properties, a correct formula might look like:LBKSif(not defined(utm_source) or utm_source == "", undefined, utm_source)LBKSOr if you're trying to check if a URL contains a UTM parameter:LBKSif(not regex_match($current_url, "utm_source="), undefined, utm_source)LBKSMixpanel's custom property formulas support various functions likeif,not,defined, andregex_matchthat you can use to create conditional logic Custom Properties Functions.kapa.ai is still learning and improving, please let me know how I did by reacting below.
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