The purpose of extra filters ( https://docs.victoriametrics.com/victorialogs/querying/#extra-filters )
is to limit the subset of logs, which can be queried. For example, it is expected that all the queries
with `extra_filters={tenant=123}` can access only logs, which contain `123` value for the `tenant` field.
Previously this wasn't the case, since the provided extra filters weren't applied to subqueries.
For example, the following query could be used to select all the logs outside `tenant=123`, for any `extra_filters` arg:
* | union({tenant!=123})
This commit fixes this by propagating extra filters to all the subqueries.
While at it, this commit also properly propagates [start, end] time range filter from HTTP querying APIs
into all the subqueries, since this is what most users expect. This behaviour can be overriden on per-subquery
basis with the `options(ignore_global_time_filter=true)` option - see https://docs.victoriametrics.com/victorialogs/logsql/#query-options
Also properly apply apply optimizations across all the subqueries. Previously the optimizations at Query.optimize()
function were applied only to the top-level query.
While at it, reduce memory allocations at Storage.getFieldValuesNoHits and make it more scalable on multi-CPU systems.
This improves performance of in(<query>) filter when the <query> returns big number of values.
This is useful for detecting patterns across log messages, which differ by various numeric fields,
with the following query:
_time:1h | collapse_nums | top 10 by (_msg)
The `first N by (field)` pipe is a shorthand to `sort by (field) limit N`,
while the `last N by (field)` pipe is a shorthand to `sort by (field) desc limit N`.
While at it, add support for partitioning sort results by log groups and applying
individual limit per each group.
For example, the following query returns up to 3 logs per each host with the biggest value
for the `request_duration` field:
_time:5m | last 3 by (request_duration) partition by (host)
This query is equivalent to the following one:
_time:5m | sort by (request_duration) desc limit 3 partition by (host)
Automatically add the 'partition by (_time)` into `sort`, `first` and `last` pipes
used in the query to `/select/logsql/stats_query_range` API.
This is needed for https://github.com/VictoriaMetrics/VictoriaMetrics/issues/7699
This eliminates possible bugs related to forgotten Query.Optimize() calls.
This also allows removing optimize() function from pipe interface.
While at it, drop filterNoop inside filterAnd.
Now the following queries are equivalents:
_time:5s | sort by (_time)
_time:5s | order by (_time)
This is needed for convenience, since `order by` is commonly used in other query languages such as SQL.
This pipe is useful for debugging purposes when the number of processed blocks must be calculated for the given query:
<query> | blocks_count
This helps detecting the root cause of query performance slowdown in cases like https://github.com/VictoriaMetrics/VictoriaMetrics/issues/7070
