update wiki pages

Vika 2019-12-10 23:01:14 +00:00
parent 99ffa727e8
commit 14e855b553

@ -9,10 +9,11 @@ Try these extensions on [an editable Grafana dashboard](http://play-grafana.vict
- Metric names and metric labels may contain escaped chars. For instance, `foo\-bar{baz\=aa="b"}` is valid expression. It returns time series with name `foo-bar` containing label `baz=aa` with value `b`. Additionally, `\xXX` escape sequence is supported, where `XX` is hexadecimal representation of escaped char.
- `offset`, range duration and step value for range vector may refer to the current step aka `$__interval` value from Grafana.
For instance, `rate(metric[10i] offset 5i)` would return per-second rate over a range covering 10 previous steps with the offset of 5 steps.
- `offset` may be put anywere in the query. For instance, `sum(foo) offset 24h`.
- `offset` may be negative. For example, `q offset -1h`.
- `default` binary operator. `q1 default q2` substitutes `NaN` values from `q1` with the corresponding values from `q2`.
- `if` binary operator. `q1 if q2` removes values from `q1` for `NaN` values from `q2`.
- `ifnot` binary operator. `q1 ifnot q2` removes values from `q1` for non-`NaN` values from `q2`.
- `offset` may be put anywere in the query. For instance, `sum(foo) offset 24h`.
- Trailing commas on all the lists are allowed - label filters, function args and with expressions. For instance, the following queries are valid: `m{foo="bar",}`, `f(a, b,)`, `WITH (x=y,) x`. This simplifies maintenance of multi-line queries.
- String literals may be concatenated. This is useful with `WITH` templates: `WITH (commonPrefix="long_metric_prefix_") {__name__=commonPrefix+"suffix1"} / {__name__=commonPrefix+"suffix2"}`.
- Range duration in functions such as [rate](https://prometheus.io/docs/prometheus/latest/querying/functions/#rate()) may be omitted. VictoriaMetrics automatically selects range duration depending on the current step used for building the graph. For instance, the following query is valid in VictoriaMetrics: `rate(node_network_receive_bytes_total)`.