diff --git a/docs/sources/logql/_index.md b/docs/sources/logql/_index.md index 4f1659f69df2..b4bf7fd3802d 100644 --- a/docs/sources/logql/_index.md +++ b/docs/sources/logql/_index.md @@ -2,7 +2,7 @@ title: LogQL weight: 700 --- -# LogQL: Log Query Language +# LogQL: Log query language LogQL is Loki's PromQL-inspired query language. Queries act as if they are a distributed `grep` to aggregate log sources. @@ -10,751 +10,13 @@ LogQL uses labels and operators for filtering. There are two types of LogQL queries: -- *Log queries* return the contents of log lines. -- *Metric queries* extend log queries to calculate values +- [Log queries](log_queries/) return the contents of log lines. +- [Metric queries](metric_queries/) extend log queries to calculate values based on query results. -## Log Queries +## Binary operators -All LogQL queries contain a **log stream selector**. - -![parts of a query](query_components.png) - -The log stream selector determines how many log streams (unique sources of log content, such as files) will be searched. -A more granular log stream selector then reduces the number of searched streams to a manageable volume. -This means that the labels passed to the log stream selector will affect the relative performance of the query's execution. - -Optionally, the log stream selector can be followed by a **log pipeline**. A log pipeline is a set of stage expressions that are chained together and applied to the selected log streams. Each expression can filter out, parse, or mutate log lines and their respective labels. - -The following example shows a full log query in action: - -```logql -{container="query-frontend",namespace="loki-dev"} |= "metrics.go" | logfmt | duration > 10s and throughput_mb < 500 -``` - -The query is composed of: - -- a log stream selector `{container="query-frontend",namespace="loki-dev"}` which targets the `query-frontend` container in the `loki-dev` namespace. -- a log pipeline `|= "metrics.go" | logfmt | duration > 10s and throughput_mb < 500` which will filter out log that contains the word `metrics.go`, then parses each log line to extract more labels and filter with them. - -> To avoid escaping special characters you can use the `` ` ``(backtick) instead of `"` when quoting strings. -For example `` `\w+` `` is the same as `"\\w+"`. -This is specially useful when writing a regular expression which contains multiple backslashes that require escaping. - -### Log Stream Selector - -The stream selector determines which log streams to include in a query's results. -The stream selector is specified by one or more comma-separated key-value pairs. Each key is a log label and each value is that label's value. -Curly braces (`{` and `}`) delimit the stream selector. - -Consider this stream selector: - -```logql -{app="mysql",name="mysql-backup"} -``` - -All log streams that have both a label of `app` whose value is `mysql` -and a label of `name` whose value is `mysql-backup` will be included in -the query results. -A stream may contain other pairs of labels and values, -but only the specified pairs within the stream selector are used to determine -which streams will be included within the query results. - -The same rules that apply for [Prometheus Label Selectors](https://prometheus.io/docs/prometheus/latest/querying/basics/#instant-vector-selectors) apply for Loki log stream selectors. - -The `=` operator after the label name is a **label matching operator**. -The following label matching operators are supported: - -- `=`: exactly equal -- `!=`: not equal -- `=~`: regex matches -- `!~`: regex does not match - -Regex log stream examples: - -- `{name =~ "mysql.+"}` -- `{name !~ "mysql.+"}` -- `` {name !~ `mysql-\d+`} `` - -**Note:** The `=~` regex operator is fully anchored, meaning regex must match against the *entire* string, including newlines. The regex `.` character does not match newlines by default. If you want the regex dot character to match newlines you can use the single-line flag, like so: `(?s)search_term.+` matches `search_term\n`. - -### Log Pipeline - -A log pipeline can be appended to a log stream selector to further process and filter log streams. It usually is composed of one or multiple expressions, each expressions is executed in sequence for each log line. If an expression filters out a log line, the pipeline will stop at this point and start processing the next line. - -Some expressions can mutate the log content and respective labels. -For example, - -``` -| line_format "{{.status_code}}"`) -``` - -will be available for further filtering and processing following expressions or metric queries. - -A log pipeline can be composed of: - -- [Line Filter Expression](#line-filter-expression) -- [Parser Expression](#parser-expression) -- [Label Filter Expression](#label-filter-expression) -- [Line Format Expression](#line-format-expression) -- [Labels Format Expression](#labels-format-expression) -- [Unwrap Expression](#unwrapped-range-aggregations). An unwrapped expression is only used within metric queries. - -#### Line Filter Expression - -The line filter expression does a distributed `grep` -over the aggregated logs from the matching log streams. -It searches the contents of the log line, -discarding those lines that do not match the case sensitive expression. - -Each line filter expression has a **filter operator** -followed by text or a regular expression. -These filter operators are supported: - -- `|=`: Log line contains string -- `!=`: Log line does not contain string -- `|~`: Log line contains a match to the regular expression -- `!~`: Log line does not contain a match to the regular expression - -Line filter expression examples: - -- Keep log lines that have the substring "error": - - ``` - |= "error" - ``` - - A complete query using this example: - - ``` - {job="mysql"} |= "error" - ``` - -- Discard log lines that have the substring "kafka.server:type=ReplicaManager": - - ``` - != "kafka.server:type=ReplicaManager" - ``` - - A complete query using this example: - - ``` - {instance=~"kafka-[23]",name="kafka"} != "kafka.server:type=ReplicaManager" - ``` - -- Keep log lines that contain a substring that starts with `tsdb-ops` and ends with `io:2003`. A complete query with a regular expression: - - ``` - {name="kafka"} |~ "tsdb-ops.*io:2003" - ``` - -- Keep log lines that contain a substring that starts with `error=`, -and is followed by 1 or more word characters. A complete query with a regular expression: - - ``` - {name="cassandra"} |~ `error=\w+` - ``` - -Filter operators can be chained. -Filters are applied sequentially. -Query results will have satisfied every filter. -This complete query example will give results that include the string `error`, -and do not include the string `timeout`. - -```logql -{job="mysql"} |= "error" != "timeout" -``` - -When using `|~` and `!~`, Go (as in [Golang](https://golang.org/)) [RE2 syntax](https://github.com/google/re2/wiki/Syntax) regex may be used. -The matching is case-sensitive by default. -Switch to case-insensitive matching by prefixing the regular expression -with `(?i)`. - -While line filter expressions could be placed anywhere within a log pipeline, -it is almost always better to have them at the beginning. -Placing them at the beginning improves the performance of the query, -as it only does further processing when a line matches. -For example, - while the results will be the same, -the query specified with - -``` -{job="mysql"} |= "error" | json | line_format "{{.err}}" -``` - -will always run faster than - -``` -{job="mysql"} | json | line_format "{{.message}}" |= "error" -``` - -Line filter expressions are the fastest way to filter logs once the -log stream selectors have been applied. - -Line filter expressions have support matching IP addresses. See [Matching IP addresses](ip/) for details. - -#### Parser Expression - -Parser expression can parse and extract labels from the log content. Those extracted labels can then be used for filtering using [label filter expressions](#label-filter-expression) or for [metric aggregations](#metric-queries). - -Extracted label keys are automatically sanitized by all parsers, to follow Prometheus metric name convention.(They can only contain ASCII letters and digits, as well as underscores and colons. They cannot start with a digit.) - -For instance, the pipeline `| json` will produce the following mapping: -```json -{ "a.b": {c: "d"}, e: "f" } -``` --> -``` -{a_b_c="d", e="f"} -``` - -In case of errors, for instance if the line is not in the expected format, the log line won't be filtered but instead will get a new `__error__` label added. - -If an extracted label key name already exists in the original log stream, the extracted label key will be suffixed with the `_extracted` keyword to make the distinction between the two labels. You can forcefully override the original label using a [label formatter expression](#labels-format-expression). However if an extracted key appears twice, only the latest label value will be kept. - -Loki supports [JSON](#json), [logfmt](#logfmt), [pattern](#pattern), [regexp](#regexp) and [unpack](#unpack) parsers. - -It's easier to use the predefined parsers `json` and `logfmt` when you can. If you can't, the `pattern` and `regexp` parsers can be used for log lines with an unusual structure. The `pattern` parser is easier and faster to write; it also outperforms the `regexp` parser. -Multiple parsers can be used by a single log pipeline. This is useful for parsing complex logs. There are examples in [Multiple parsers](#multiple-parsers). - -##### JSON - -The **json** parser operates in two modes: - -1. **without** parameters: - - Adding `| json` to your pipeline will extract all json properties as labels if the log line is a valid json document. - Nested properties are flattened into label keys using the `_` separator. - - Note: **Arrays are skipped**. - - For example the json parsers will extract from the following document: - - ```json - { - "protocol": "HTTP/2.0", - "servers": ["129.0.1.1","10.2.1.3"], - "request": { - "time": "6.032", - "method": "GET", - "host": "foo.grafana.net", - "size": "55", - "headers": { - "Accept": "*/*", - "User-Agent": "curl/7.68.0" - } - }, - "response": { - "status": 401, - "size": "228", - "latency_seconds": "6.031" - } - } - ``` - - The following list of labels: - - ```kv - "protocol" => "HTTP/2.0" - "request_time" => "6.032" - "request_method" => "GET" - "request_host" => "foo.grafana.net" - "request_size" => "55" - "response_status" => "401" - "response_size" => "228" - "response_size" => "228" - ``` - -2. **with** parameters: - - Using `| json label="expression", another="expression"` in your pipeline will extract only the - specified json fields to labels. You can specify one or more expressions in this way, the same - as [`label_format`](#labels-format-expression); all expressions must be quoted. - - Currently, we only support field access (`my.field`, `my["field"]`) and array access (`list[0]`), and any combination - of these in any level of nesting (`my.list[0]["field"]`). - - For example, `| json first_server="servers[0]", ua="request.headers[\"User-Agent\"]` will extract from the following document: - - ```json - { - "protocol": "HTTP/2.0", - "servers": ["129.0.1.1","10.2.1.3"], - "request": { - "time": "6.032", - "method": "GET", - "host": "foo.grafana.net", - "size": "55", - "headers": { - "Accept": "*/*", - "User-Agent": "curl/7.68.0" - } - }, - "response": { - "status": 401, - "size": "228", - "latency_seconds": "6.031" - } - } - ``` - - The following list of labels: - - ```kv - "first_server" => "129.0.1.1" - "ua" => "curl/7.68.0" - ``` - - If an array or an object returned by an expression, it will be assigned to the label in json format. - - For example, `| json server_list="servers", headers="request.headers` will extract: - - ```kv - "server_list" => `["129.0.1.1","10.2.1.3"]` - "headers" => `{"Accept": "*/*", "User-Agent": "curl/7.68.0"}` - ``` - -##### logfmt - -The **logfmt** parser can be added using the `| logfmt` and will extract all keys and values from the [logfmt](https://brandur.org/logfmt) formatted log line. - -For example the following log line: - -```logfmt -at=info method=GET path=/ host=grafana.net fwd="124.133.124.161" service=8ms status=200 -``` - -will get those labels extracted: - -```kv -"at" => "info" -"method" => "GET" -"path" => "/" -"host" => "grafana.net" -"fwd" => "124.133.124.161" -"service" => "8ms" -"status" => "200" -``` - -##### Pattern - -The pattern parser is a beta feature. - -The pattern parser allows the explicit extraction of fields from log lines by defining a pattern expression (`| pattern ""`). The expression matches the structure of a log line. - -Consider this NGINX log line. - -```log -0.191.12.2 - - [10/Jun/2021:09:14:29 +0000] "GET /api/plugins/versioncheck HTTP/1.1" 200 2 "-" "Go-http-client/2.0" "13.76.247.102, 34.120.177.193" "TLSv1.2" "US" "" -``` - -This log line can be parsed with the expression - -` - - <_> " <_>" <_> "" <_>` - -to extract these fields: - -```kv -"ip" => "0.191.12.2" -"method" => "GET" -"uri" => "/api/plugins/versioncheck" -"status" => "200" -"size" => "2" -"agent" => "Go-http-client/2.0" -``` - -A pattern expression is composed of captures and literals. - -A capture is a field name delimited by the `<` and `>` characters. `` defines the field name `example`. -An unnamed capture appears as `<_>`. The unnamed capture skips matched content. - -Captures are matched from the line beginning or the previous set of literals, to the line end or the next set of literals. -If a capture is not matched, the pattern parser will stop. - -Literals can be any sequence of UTF-8 characters, including whitespace characters. - -By default, a pattern expression is anchored at the start of the log line. If the expression start with literals, then the log line must also start with the same set of literals. Use `<_>` at the beginning of the expression to anchor the expression at the start. - -Consider the log line - -```log -level=debug ts=2021-06-10T09:24:13.472094048Z caller=logging.go:66 traceID=0568b66ad2d9294c msg="POST /loki/api/v1/push (204) 16.652862ms" -``` - -To match `msg="`, use the expression: - -```pattern -<_> msg=" () " -``` - -A pattern expression is invalid if - -- It does not contain any named capture. -- It contains two consecutive captures not separated by whitespace characters. - -##### regexp - -Unlike the logfmt and json, which extract implicitly all values and takes no parameters, the **regexp** parser takes a single parameter `| regexp ""` which is the regular expression using the [Golang](https://golang.org/) [RE2 syntax](https://github.com/google/re2/wiki/Syntax). - -The regular expression must contain a least one named sub-match (e.g `(?Pre)`), each sub-match will extract a different label. - -For example the parser `| regexp "(?P\\w+) (?P[\\w|/]+) \\((?P\\d+?)\\) (?P.*)"` will extract from the following line: - -```log -POST /api/prom/api/v1/query_range (200) 1.5s -``` - -those labels: - -```kv -"method" => "POST" -"path" => "/api/prom/api/v1/query_range" -"status" => "200" -"duration" => "1.5s" -``` - -##### unpack - -The `unpack` parser parses a JSON log line, unpacking all embedded labels in the [`pack`](../clients/promtail/stages/pack/) stage. -**A special property `_entry` will also be used to replace the original log line**. - -For example, using `| unpack` with the log line: - -```json -{ - "container": "myapp", - "pod": "pod-3223f", - "_entry": "original log message" -} -``` - -extracts the `container` and `pod` labels; it sets `original log message` as the new log line. - -You can combine the `unpack` and `json` parsers (or any other parsers) if the original embedded log line is of a specific format. - -#### Label Filter Expression - -Label filter expression allows filtering log line using their original and extracted labels. It can contain multiple predicates. - -A predicate contains a **label identifier**, an **operation** and a **value** to compare the label with. - -For example with `cluster="namespace"` the cluster is the label identifier, the operation is `=` and the value is "namespace". The label identifier is always on the right side of the operation. - -We support multiple **value** types which are automatically inferred from the query input. - -- **String** is double quoted or backticked such as `"200"` or \``us-central1`\`. -- **[Duration](https://golang.org/pkg/time/#ParseDuration)** is a sequence of decimal numbers, each with optional fraction and a unit suffix, such as "300ms", "1.5h" or "2h45m". Valid time units are "ns", "us" (or "µs"), "ms", "s", "m", "h". -- **Number** are floating-point number (64bits), such as`250`, `89.923`. -- **Bytes** is a sequence of decimal numbers, each with optional fraction and a unit suffix, such as "42MB", "1.5Kib" or "20b". Valid bytes units are "b", "kib", "kb", "mib", "mb", "gib", "gb", "tib", "tb", "pib", "pb", "eib", "eb". - -String type work exactly like Prometheus label matchers use in [log stream selector](#log-stream-selector). This means you can use the same operations (`=`,`!=`,`=~`,`!~`). - -> The string type is the only one that can filter out a log line with a label `__error__`. - -Using Duration, Number and Bytes will convert the label value prior to comparision and support the following comparators: - -- `==` or `=` for equality. -- `!=` for inequality. -- `>` and `>=` for greater than and greater than or equal. -- `<` and `<=` for lesser than and lesser than or equal. - -For instance, `logfmt | duration > 1m and bytes_consumed > 20MB` - -If the conversion of the label value fails, the log line is not filtered and an `__error__` label is added. To filters those errors see the [pipeline errors](#pipeline-errors) section. - -You can chain multiple predicates using `and` and `or` which respectively express the `and` and `or` binary operations. `and` can be equivalently expressed by a comma, a space or another pipe. Label filters can be place anywhere in a log pipeline. - -This means that all the following expressions are equivalent: - -```logql -| duration >= 20ms or size == 20kb and method!~"2.." -| duration >= 20ms or size == 20kb | method!~"2.." -| duration >= 20ms or size == 20kb , method!~"2.." -| duration >= 20ms or size == 20kb method!~"2.." - -``` - -By default the precedence of multiple predicates is right to left. You can wrap predicates with parenthesis to force a different precedence left to right. - -For example the following are equivalent. - -```logql -| duration >= 20ms or method="GET" and size <= 20KB -| ((duration >= 20ms or method="GET") and size <= 20KB) -``` - -It will evaluate first `duration >= 20ms or method="GET"`. To evaluate first `method="GET" and size <= 20KB`, make sure to use proper parenthesis as shown below. - -```logql -| duration >= 20ms or (method="GET" and size <= 20KB) -``` - -> Label filter expressions are the only expression allowed after the [unwrap expression](#unwrapped-range-aggregations). This is mainly to allow filtering errors from the metric extraction (see [errors](#pipeline-errors)). - -Label filter expressions have support matching IP addresses. See [Matching IP addresses](ip/) for details. - -#### Line Format Expression - -The line format expression can rewrite the log line content by using the [text/template](https://golang.org/pkg/text/template/) format. -It takes a single string parameter `| line_format "{{.label_name}}"`, which is the template format. All labels are injected variables into the template and are available to use with the `{{.label_name}}` notation. - -For example the following expression: - -```logql -{container="frontend"} | logfmt | line_format "{{.query}} {{.duration}}" -``` - -Will extract and rewrite the log line to only contains the query and the duration of a request. - -You can use double quoted string for the template or backticks `` `{{.label_name}}` `` to avoid the need to escape special characters. - -`line_format` also supports `math` functions. Example: - -If we have the following labels `ip=1.1.1.1`, `status=200` and `duration=3000`(ms), we can divide the duration by `1000` to get the value in seconds. - -```logql -{container="frontend"} | logfmt | line_format "{{.ip}} {{.status}} {{div .duration 1000}}" -``` - -The above query will give us the `line` as `1.1.1.1 200 3` - -See [template functions](template_functions/) to learn about available functions in the template format. - -#### Labels Format Expression - -The `| label_format` expression can rename, modify or add labels. It takes as parameter a comma separated list of equality operations, enabling multiple operations at once. - -When both side are label identifiers, for example `dst=src`, the operation will rename the `src` label into `dst`. - -The left side can alternatively be a template string (double quoted or backtick), for example `dst="{{.status}} {{.query}}"`, in which case the `dst` label value is replaced by the result of the [text/template](https://golang.org/pkg/text/template/) evaluation. This is the same template engine as the `| line_format` expression, which means labels are available as variables and you can use the same list of [functions](functions/). - -In both cases, if the destination label doesn't exist, then a new one is created. - -The renaming form `dst=src` will _drop_ the `src` label after remapping it to the `dst` label. However, the _template_ form will preserve the referenced labels, such that `dst="{{.src}}"` results in both `dst` and `src` having the same value. - -> A single label name can only appear once per expression. This means `| label_format foo=bar,foo="new"` is not allowed but you can use two expressions for the desired effect: `| label_format foo=bar | label_format foo="new"` - -### Log Queries Examples - -#### Multiple filtering - -Filtering should be done first using label matchers, then line filters (when possible) and finally using label filters. The following query demonstrate this. - -```logql -{cluster="ops-tools1", namespace="loki-dev", job="loki-dev/query-frontend"} |= "metrics.go" !="out of order" | logfmt | duration > 30s or status_code!="200" -``` - -#### Multiple parsers - -To extract the method and the path of the following logfmt log line: - -```log -level=debug ts=2020-10-02T10:10:42.092268913Z caller=logging.go:66 traceID=a9d4d8a928d8db1 msg="POST /api/prom/api/v1/query_range (200) 1.5s" -``` - -You can use multiple parsers (logfmt and regexp) like this. - -```logql -{job="cortex-ops/query-frontend"} | logfmt | line_format "{{.msg}}" | regexp "(?P\\w+) (?P[\\w|/]+) \\((?P\\d+?)\\) (?P.*)" -``` - -This is possible because the `| line_format` reformats the log line to become `POST /api/prom/api/v1/query_range (200) 1.5s` which can then be parsed with the `| regexp ...` parser. - -#### Formatting - -The following query shows how you can reformat a log line to make it easier to read on screen. - -```logql -{cluster="ops-tools1", name="querier", namespace="loki-dev"} - |= "metrics.go" != "loki-canary" - | logfmt - | query != "" - | label_format query="{{ Replace .query \"\\n\" \"\" -1 }}" - | line_format "{{ .ts}}\t{{.duration}}\ttraceID = {{.traceID}}\t{{ printf \"%-100.100s\" .query }} " -``` - -Label formatting is used to sanitize the query while the line format reduce the amount of information and creates a tabular output. - -For those given log line: - -```log -level=info ts=2020-10-23T20:32:18.094668233Z caller=metrics.go:81 org_id=29 traceID=1980d41501b57b68 latency=fast query="{cluster=\"ops-tools1\", job=\"cortex-ops/query-frontend\"} |= \"query_range\"" query_type=filter range_type=range length=15m0s step=7s duration=650.22401ms status=200 throughput_mb=1.529717 total_bytes_mb=0.994659 -level=info ts=2020-10-23T20:32:18.068866235Z caller=metrics.go:81 org_id=29 traceID=1980d41501b57b68 latency=fast query="{cluster=\"ops-tools1\", job=\"cortex-ops/query-frontend\"} |= \"query_range\"" query_type=filter range_type=range length=15m0s step=7s duration=624.008132ms status=200 throughput_mb=0.693449 total_bytes_mb=0.432718 -``` - -The result would be: - -```log -2020-10-23T20:32:18.094668233Z 650.22401ms traceID = 1980d41501b57b68 {cluster="ops-tools1", job="cortex-ops/query-frontend"} |= "query_range" -2020-10-23T20:32:18.068866235Z 624.008132ms traceID = 1980d41501b57b68 {cluster="ops-tools1", job="cortex-ops/query-frontend"} |= "query_range" -``` - -## Metric Queries - -LogQL supports applying a function to log query results. -This powerful feature creates metrics from logs. - -Metric queries can be used to calculate things such as the rate of error messages, or the top N log sources with the most amount of logs over the last 3 hours. - -Combined with log parsers, metrics queries can also be used to calculate metrics from a sample value within the log line, such as latency or request size. -All labels, including extracted ones, will be available for aggregations and generation of new series. - -### Range Vector aggregation - -LogQL shares the [range vector](https://prometheus.io/docs/prometheus/latest/querying/basics/#range-vector-selectors) concept of Prometheus. -In Loki, the selected range of samples is a range of selected log or label values. - -The aggregation is applied over a time duration. -Loki defines [Time Durations](https://prometheus.io/docs/prometheus/latest/querying/basics/#time-durations) with the same syntax as Prometheus. - -Loki supports two types of range vector aggregations: log range aggregations and unwrapped range aggregations. - -#### Log Range Aggregations - -A log range aggregation is a query followed by a duration. -A function is applied to aggregate the query over the duration. -The duration can be placed -after the log stream selector or at end of the log pipeline. - -The functions: - -- `rate(log-range)`: calculates the number of entries per second -- `count_over_time(log-range)`: counts the entries for each log stream within the given range. -- `bytes_rate(log-range)`: calculates the number of bytes per second for each stream. -- `bytes_over_time(log-range)`: counts the amount of bytes used by each log stream for a given range. -- `absent_over_time(log-range)`: returns an empty vector if the range vector passed to it has any elements and a 1-element vector with the value 1 if the range vector passed to it has no elements. (`absent_over_time` is useful for alerting on when no time series and logs stream exist for label combination for a certain amount of time.) - -Examples: - -- Count all the log lines within the last five minutes for the MySQL job. - - ```logql - count_over_time({job="mysql"}[5m]) - ``` - -- This aggregation includes filters and parsers. - It returns the per-second rate of all non-timeout errors within the last minutes per host for the MySQL job and only includes errors whose duration is above ten seconds. - - ```logql - sum by (host) (rate({job="mysql"} |= "error" != "timeout" | json | duration > 10s [1m])) - ``` - -#### Unwrapped Range Aggregations - -Unwrapped ranges uses extracted labels as sample values instead of log lines. However to select which label will be used within the aggregation, the log query must end with an unwrap expression and optionally a label filter expression to discard [errors](#pipeline-errors). - -The unwrap expression is noted `| unwrap label_identifier` where the label identifier is the label name to use for extracting sample values. - -Since label values are string, by default a conversion into a float (64bits) will be attempted, in case of failure the `__error__` label is added to the sample. -Optionally the label identifier can be wrapped by a conversion function `| unwrap (label_identifier)`, which will attempt to convert the label value from a specific format. - -We currently support the functions: -- `duration_seconds(label_identifier)` (or its short equivalent `duration`) which will convert the label value in seconds from the [go duration format](https://golang.org/pkg/time/#ParseDuration) (e.g `5m`, `24s30ms`). -- `bytes(label_identifier)` which will convert the label value to raw bytes applying the bytes unit (e.g. `5 MiB`, `3k`, `1G`). - -Supported function for operating over unwrapped ranges are: - -- `rate(unwrapped-range)`: calculates per second rate of all values in the specified interval. -- `sum_over_time(unwrapped-range)`: the sum of all values in the specified interval. -- `avg_over_time(unwrapped-range)`: the average value of all points in the specified interval. -- `max_over_time(unwrapped-range)`: the maximum value of all points in the specified interval. -- `min_over_time(unwrapped-range)`: the minimum value of all points in the specified interval -- `first_over_time(unwrapped-range)`: the first value of all points in the specified interval -- `last_over_time(unwrapped-range)`: the last value of all points in the specified interval -- `stdvar_over_time(unwrapped-range)`: the population standard variance of the values in the specified interval. -- `stddev_over_time(unwrapped-range)`: the population standard deviation of the values in the specified interval. -- `quantile_over_time(scalar,unwrapped-range)`: the φ-quantile (0 ≤ φ ≤ 1) of the values in the specified interval. -- `absent_over_time(unwrapped-range)`: returns an empty vector if the range vector passed to it has any elements and a 1-element vector with the value 1 if the range vector passed to it has no elements. (`absent_over_time` is useful for alerting on when no time series and logs stream exist for label combination for a certain amount of time.) - -Except for `sum_over_time`,`absent_over_time` and `rate`, unwrapped range aggregations support grouping. - -```logql -([parameter,] ) [without|by (