Unable to use other aggregation than 'count'

[pueffl]

As I got now answer in the forums, I announce this as a possible bug:

I want to create a View which shows an average request time in Kibana (which worked in Kibana 3). I have configured the conversion of the according Integer-String in Logstash as follows:

mutate {
convert => ["request_time", "integer"]
}

In Kibana, I see 'request_time' marked with an exclamation mark in a triangle (no idea what that means exactly, I found no information about this).
The I try to create a Visualization: When I want to do an Y-Axis Aggregation and select 'Average' as the Addregation, I get an empty Field-DDLB where I would expet at least 'request_time' to select as the base to build the calculation.

[pueffl]

Find out some additional information:
-) Every field in the kibana Discover tab has something like a type indicator on the left (some additional information would be very helpful here when you hover over the icon or when you click on it.)
-) It is even not possible to create the view when you create a query where the field to calculate is definitely set -> So this must be a bug.

[rashidkpc]

Its likely that your request_time field is mapped as a string in some of you indices and a number in others. When this happens Kibana will refuse to aggregate on this field as it will cause Elasticsearch to throw exceptions. Thus, Kibana 4 requires that the field be mapped consistently across indices in the pattern and will display the warning triangle when it isn't.

If you need more help troubleshooting this please join us in #kibana on freenode.