/api/query/exp

/api/query/exp

This endpoint allows for querying data using expressions. The query is broken up into different sections.

Two set operations (or Joins) are allowed. The union of all time series ore the intersection.

For example we can compute "a + b" with a group by on the host field. Both metrics queried alone would emit a time series per host, e.g. maybe one for "web01", "web02" and "web03". Lets say metric "a" has values for all 3 hosts but metric "b" is missing "web03".

With the intersection operator, the expression will effectively add "a.web01 + b.web01" and "a.web02 + b.web02" but will skip emitting anything for "web03". Be aware of this if you see fewer outputs that you expected or you see errors about no series available after intersection.

With the union operator the expression will add the web01 and web02