I have a few dashboards that use expressions like
...which assigns "true" or "false" to var depending on x being NULL
Those dashboards still work, but I notice that ifnull() does not show up in any of the current documentation, and it seems the current way to get the same result would be
Did I miss some kind of deprecation of that syntax ages ago (must have been before 6.3.0), and it just happens to still be parsed?
I can't say I've ever seen ifnull documented, but system/default/searchbnf.conf says it's an alias for coalesce.
View solution in original post
Huh. Reading the documentation for coalesce, I can see how this happens to work for specific cases where you want to keep the original value of x if it's not NULL, and fill in something else if it is.
...which is not what I showed in my example above, but exactly what happens in the dashboard I'm looking at, and where the third parameter is just bogus. Ouch.