Parent-Child Filters allow a filter's options depend on the values selected in another filter. For example, a "Device" filter could only show the devices that match the selected platforms in a "Platform" filter.
To start, a parent filter is needed. Let us call it "Platform." The parent filter can be created like a regular filter.
In the filter SQL box, we use:
Once the parent filter has been made, a child filter can be created! Let us call it "Device."
In the child filter we use:
The child filter needs three values to be select in the following order: child filter value, child display value, and parent matching value. In this case, the child filter values and the child display value are the same, thus device is selected twice.
With this child filter query, it it ready to be linked to the parent filter!
Expanding out "More Options," click the "Make this filter a child of" checkbox and select "Device" in the dropdown.
To use dependent filters in charts, one or both filters can be used in the query the same way regular filters are used: "where [my_column_name=FilterName]".
Now when a specific platform is selected, only devices on that platform will be populated in the Device filter.