Commit Graph

211 Commits

Author SHA1 Message Date
frankgrimes97 2f98675285
Tuple sketch SQL support (#13887)
This PR is a follow-up to #13819 so that the Tuple sketch functionality can be used in SQL for both ingestion using Multi-Stage Queries (MSQ) and also for analytic queries against Tuple sketch columns.
2023-03-28 18:47:12 +05:30
Jill Osborne 4f95285406
Correct nested columns JSON example (#13953) 2023-03-21 09:17:26 -07:00
317brian 65a663adbb
docs: clarify Java precision (#13671)
Co-authored-by: Katya Macedo  <38017980+ektravel@users.noreply.github.com>
Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>
2023-03-15 11:43:41 -07:00
somu-imply a7ba361666
Refactoring and bug fixes on top of unnest. The allowList now is not passed … (#13922)
* Refactoring and bug fixes on top of unnest. The filter now is passed inside the unnest cursors. Added tests for scenarios such as
1. filter on unnested column which involves a left filter rewrite
2. filter on unnested virtual column which pushes the filter to the right only and involves no rewrite
3. not filters
4. SQL functions applied on top of unnested column
5. null present in first row of the column to be unnested
2023-03-14 16:05:56 -07:00
Gian Merlino 4b1ffbc452
Various changes and fixes to UNNEST. (#13892)
* Various changes and fixes to UNNEST.

Native changes:

1) UnnestDataSource: Replace "column" and "outputName" with "virtualColumn".
   This enables pushing expressions into the datasource. This in turn
   allows us to do the next thing...

2) UnnestStorageAdapter: Logically apply query-level filters and virtual
   columns after the unnest operation. (Physically, filters are pulled up,
   when possible.) This is beneficial because it allows filters and
   virtual columns to reference the unnested column, and because it is
   consistent with how the join datasource works.

3) Various documentation updates, including declaring "unnest" as an
   experimental feature for now.

SQL changes:

1) Rename DruidUnnestRel (& Rule) to DruidUnnestRel (& Rule). The rel
   is simplified: it only handles the UNNEST part of a correlated join.
   Constant UNNESTs are handled with regular inline rels.

2) Rework DruidCorrelateUnnestRule to focus on pulling Projects from
   the left side up above the Correlate. New test testUnnestTwice verifies
   that this works even when two UNNESTs are stacked on the same table.

3) Include ProjectCorrelateTransposeRule from Calcite to encourage
   pushing mappings down below the left-hand side of the Correlate.

4) Add a new CorrelateFilterLTransposeRule and CorrelateFilterRTransposeRule
   to handle pulling Filters up above the Correlate. New tests
   testUnnestWithFiltersOutside and testUnnestTwiceWithFilters verify
   this behavior.

5) Require a context feature flag for SQL UNNEST, since it's undocumented.
   As part of this, also cleaned up how we handle feature flags in SQL.
   They're now hooked into EngineFeatures, which is useful because not
   all engines support all features.
2023-03-10 16:42:08 +05:30
Gian Merlino fe9d0c46d5
Improve memory efficiency of WrappedRoaringBitmap. (#13889)
* Improve memory efficiency of WrappedRoaringBitmap.

Two changes:

1) Use an int[] for sizes 4 or below.
2) Remove the boolean compressRunOnSerialization. Doesn't save much
   space, but it does save a little, and it isn't adding a ton of value
   to have it be configurable. It was originally configurable in case
   anything broke when enabling it, but it's been a while and nothing
   has broken.

* Slight adjustment.

* Adjust for inspection.

* Updates.

* Update snaps.

* Update test.

* Adjust test.

* Fix snaps.
2023-03-09 15:48:02 -08:00
Gian Merlino 82f7a56475
Sort-merge join and hash shuffles for MSQ. (#13506)
* Sort-merge join and hash shuffles for MSQ.

The main changes are in the processing, multi-stage-query, and sql modules.

processing module:

1) Rename SortColumn to KeyColumn, replace boolean descending with KeyOrder.
   This makes it nicer to model hash keys, which use KeyOrder.NONE.

2) Add nullability checkers to the FieldReader interface, and an
   "isPartiallyNullKey" method to FrameComparisonWidget. The join
   processor uses this to detect null keys.

3) Add WritableFrameChannel.isClosed and OutputChannel.isReadableChannelReady
   so callers can tell which OutputChannels are ready for reading and which
   aren't.

4) Specialize FrameProcessors.makeCursor to return FrameCursor, a random-access
   implementation. The join processor uses this to rewind when it needs to
   replay a set of rows with a particular key.

5) Add MemoryAllocatorFactory, which is embedded inside FrameWriterFactory
   instead of a particular MemoryAllocator. This allows FrameWriterFactory
   to be shared in more scenarios.

multi-stage-query module:

1) ShuffleSpec: Add hash-based shuffles. New enum ShuffleKind helps callers
   figure out what kind of shuffle is happening. The change from SortColumn
   to KeyColumn allows ClusterBy to be used for both hash-based and sort-based
   shuffling.

2) WorkerImpl: Add ability to handle hash-based shuffles. Refactor the logic
   to be more readable by moving the work-order-running code to the inner
   class RunWorkOrder, and the shuffle-pipeline-building code to the inner
   class ShufflePipelineBuilder.

3) Add SortMergeJoinFrameProcessor and factory.

4) WorkerMemoryParameters: Adjust logic to reserve space for output frames
   for hash partitioning. (We need one frame per partition.)

sql module:

1) Add sqlJoinAlgorithm context parameter; can be "broadcast" or
   "sortMerge". With native, it must always be "broadcast", or it's a
   validation error. MSQ supports both. Default is "broadcast" in
   both engines.

2) Validate that MSQs do not use broadcast join with RIGHT or FULL join,
   as results are not correct for broadcast join with those types. Allow
   this in native for two reasons: legacy (the docs caution against it,
   but it's always been allowed), and the fact that it actually *does*
   generate correct results in native when the join is processed on the
   Broker. It is much less likely that MSQ will plan in such a way that
   generates correct results.

3) Remove subquery penalty in DruidJoinQueryRel when using sort-merge
   join, because subqueries are always required, so there's no reason
   to penalize them.

4) Move previously-disabled join reordering and manipulation rules to
   FANCY_JOIN_RULES, and enable them when using sort-merge join. Helps
   get to better plans where projections and filters are pushed down.

* Work around compiler problem.

* Updates from static analysis.

* Fix @param tag.

* Fix declared exception.

* Fix spelling.

* Minor adjustments.

* wip

* Merge fixups

* fixes

* Fix CalciteSelectQueryMSQTest

* Empty keys are sortable.

* Address comments from code review. Rename mux -> mix.

* Restore inspection config.

* Restore original doc.

* Reorder imports.

* Adjustments

* Fix.

* Fix imports.

* Adjustments from review.

* Update header.

* Adjust docs.
2023-03-08 14:19:39 -08:00
Adarsh Sanjeev ef82756176
Add validation for aggregations on __time (#13793)
* Add validation for aggregations on __time
2023-03-07 17:16:36 -08:00
317brian b4b354b658
docs: fix html nits (#13835) 2023-03-02 11:19:32 -08:00
Apoorv Gupta b26f1b4a5d
Update datasources.md: Fix Documentation. (#13865)
Fixed documentation to clarify that union query cant be run over query datasources.
2023-03-01 20:29:15 +05:30
benkrug 66034dd8bc
Update default for finalize in query-context.md (#13763)
Co-authored-by: Katya Macedo  <38017980+ektravel@users.noreply.github.com>

---------

Co-authored-by: Charles Smith <techdocsmith@gmail.com>
Co-authored-by: Katya Macedo  <38017980+ektravel@users.noreply.github.com>
2023-02-22 12:35:36 -08:00
Paul Rogers 85d36be085
Information schema now uses numeric column types (#13777)
Change to use SQL schemas to allow null numeric columns

* Updated docs
2023-02-17 14:39:31 -08:00
Kashif Faraz f629643c50
Fix value of lookup sync period in docs (#13695)
* Fix lookup docs

* Fix spelling

* Apply suggestions from code review

Co-authored-by: Charles Smith <techdocsmith@gmail.com>

---------

Co-authored-by: Charles Smith <techdocsmith@gmail.com>
2023-02-01 18:12:00 -08:00
Tijo Thomas 1beef30bb2
Support postaggregation function as in Math.pow() (#13703) (#13704)
Support postaggregation function as in Math.pow()
2023-01-31 22:55:04 +05:30
Vadim Ogievetsky 93dc01b6c5
fix broken table missing new line (#13666) 2023-01-12 15:29:51 -08:00
Victoria Lim a800dae87a
doc: List Protobuf as a supported format (#13640) 2023-01-06 15:09:37 -08:00
317brian 6bbf4266b2
docs: documentation for unnest datasource (#13479)
Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>
2023-01-06 11:41:11 -08:00
Gian Merlino 7f3c117e3a
SQL: Improve docs around casts. (#13466)
Main change: clarify that the "default value" for casts only applies if
druid.generic.useDefaultValueForNull = true.

Secondary change: adjust a bunch of wording from future to present tense.
2022-12-15 15:01:40 -08:00
Katya Macedo 78c1a2bd66
Remove limit from timeseries (#13457)
CI build failures seem unrelated to docs
2022-12-02 12:19:59 -08:00
Jill Osborne 138a6de507
Update nested columns docs (#13461)
* Update nested columns docs

(cherry picked from commit 04206c5179)

* Update nested-columns.md

(cherry picked from commit 8085ee7217)
2022-12-01 10:47:32 -08:00
317brian cc2e4a80ff
doc: add a basic JDBC tutorial (#13343)
* initial commit for jdbc tutorial

(cherry picked from commit 04c4adad71e5436b76c3425fe369df03aaaf0acb)

* add commentary

* address comments from charles

* add query context to example

* fix typo

* add links

* Apply suggestions from code review

Co-authored-by: Frank Chen <frankchen@apache.org>

* fix datatype

* address feedback

* add parameterize to spelling file. the past tense version was already there

Co-authored-by: Frank Chen <frankchen@apache.org>
2022-11-30 16:25:35 -08:00
Jill Osborne 100a2aa4a2
Update and document experimental features (#13348)
* Update and document experimental features
* Updated
* Update experimental-features.md
* Update docs/development/experimental-features.md
Co-authored-by: Abhishek Agarwal <1477457+abhishekagarwal87@users.noreply.github.com>
* Updated after review
* Updated
* Update materialized-view.md
* Update experimental-features.md
Co-authored-by: Abhishek Agarwal <1477457+abhishekagarwal87@users.noreply.github.com>
2022-11-29 08:01:28 +05:30
Andreas Maechler 03175a2b8d
Add missing MSQ error code fields to docs (#13308)
* Fix typo

* Fix some spacing

* Add missing fields

* Cleanup table spacing

* Remove durable storage docs again

Thanks Brian for pointing out previous discussions.

* Update docs/multi-stage-query/reference.md

Co-authored-by: Charles Smith <techdocsmith@gmail.com>

* Mark codes as code

* And even more codes as code

* Another set of spaces

* Combine `ColumnTypeNotSupported`

Thanks Karan.

* More whitespaces and typos

* Add spelling and fix links

Co-authored-by: Charles Smith <techdocsmith@gmail.com>
2022-11-10 21:03:04 +05:30
Jill Osborne 965e41538e
Update nested columns doc (#13314)
* Updated nested columns doc

* Update nested-columns.md

* Update nested-columns.md
2022-11-10 09:53:28 +08:00
Gian Merlino 8f90589ce5
Always return sketches from DS_HLL, DS_THETA, DS_QUANTILES_SKETCH. (#13247)
* Always return sketches from DS_HLL, DS_THETA, DS_QUANTILES_SKETCH.

These aggregation functions are documented as creating sketches. However,
they are planned into native aggregators that include finalization logic
to convert the sketch to a number of some sort. This creates an
inconsistency: the functions sometimes return sketches, and sometimes
return numbers, depending on where they lie in the native query plan.

This patch changes these SQL aggregators to _never_ finalize, by using
the "shouldFinalize" feature of the native aggregators. It already
existed for theta sketches. This patch adds the feature for hll and
quantiles sketches.

As to impact, Druid finalizes aggregators in two cases:

- When they appear in the outer level of a query (not a subquery).
- When they are used as input to an expression or finalizing-field-access
  post-aggregator (not any other kind of post-aggregator).

With this patch, the functions will no longer be finalized in these cases.

The second item is not likely to matter much. The SQL functions all declare
return type OTHER, which would be usable as an input to any other function
that makes sense and that would be planned into an expression.

So, the main effect of this patch is the first item. To provide backwards
compatibility with anyone that was depending on the old behavior, the
patch adds a "sqlFinalizeOuterSketches" query context parameter that
restores the old behavior.

Other changes:

1) Move various argument-checking logic from runtime to planning time in
   DoublesSketchListArgBaseOperatorConversion, by adding an OperandTypeChecker.

2) Add various JsonIgnores to the sketches to simplify their JSON representations.

3) Allow chaining of ExpressionPostAggregators and other PostAggregators
   in the SQL layer.

4) Avoid unnecessary FieldAccessPostAggregator wrapping in the SQL layer,
   now that expressions can operate on complex inputs.

5) Adjust return type to thetaSketch (instead of OTHER) in
   ThetaSketchSetBaseOperatorConversion.

* Fix benchmark class.

* Fix compilation error.

* Fix ThetaSketchSqlAggregatorTest.

* Hopefully fix ITAutoCompactionTest.

* Adjustment to ITAutoCompactionTest.
2022-11-03 09:43:00 -07:00
arvindanugula 42384d85e7
Update nested-columns.md (#13227)
typo error corrected.
2022-10-14 16:15:46 -07:00
Victoria Lim 02ad62a08c
Docs: update description of query priority default value (#13191)
* update description of default for query priority

* update order

* update terms

* standardize to query context parameters
2022-10-14 14:28:04 -07:00
Jill Osborne 548d810baa
Correct nested columns example (#13150) 2022-09-28 10:39:56 +05:30
Apoorv Gupta c8f4d72fb1
Fix documentation bug about injective lookups (#13147)
replace mapping to `unique keys` with mapping to `unique values`.
2022-09-27 10:16:48 +08:00
hosswald 5ed5c83aab
Clarified the behaviour of SQL COUNT(DISTINCT dim) on multi-value dimensions (#13128)
* Clarified the behaviour of COUNT(DISTINCT column) on multi-value columns

* Update docs/querying/sql-aggregations.md

Co-authored-by: Charles Smith <techdocsmith@gmail.com>

Co-authored-by: Vadim Ogievetsky <vadimon@gmail.com>
Co-authored-by: Charles Smith <techdocsmith@gmail.com>
2022-09-20 18:03:34 -07:00
Vadim Ogievetsky bb0b810b1d
fix html tags in docs (#13117)
* fix html tags in docs

* revert not null
2022-09-18 19:40:33 -07:00
Gian Merlino d4967c38f8
Various documentation updates. (#13107)
* Various documentation updates.

1) Split out "data management" from "ingestion". Break it into thematic pages.

2) Move "SQL-based ingestion" into the Ingestion category. Adjust content so
   all conceptual content is in concepts.md and all syntax content is in reference.md.
   Shorten the known issues page to the most interesting ones.

3) Add SQL-based ingestion to the ingestion method comparison page. Remove the
   index task, since index_parallel is just as good when maxNumConcurrentSubTasks: 1.

4) Rename various mentions of "Druid console" to "web console".

5) Add additional information to ingestion/partitioning.md.

6) Remove a mention of Tranquility.

7) Remove a note about upgrading to Druid 0.10.1.

8) Remove no-longer-relevant task types from ingestion/tasks.md.

9) Move ingestion/native-batch-firehose.md to the hidden section. It was previously deprecated.

10) Move ingestion/native-batch-simple-task.md to the hidden section. It is still linked in some
    places, but it isn't very useful compared to index_parallel, so it shouldn't take up space
    in the sidebar.

11) Make all br tags self-closing.

12) Certain other cosmetic changes.

13) Update to node-sass 7.

* make travis use node12 for docs

Co-authored-by: Vadim Ogievetsky <vadim@ogievetsky.com>
2022-09-16 21:58:11 -07:00
Jill Osborne 1f69140623
Nested columns documentation (#12946)
Co-authored-by: Clint Wylie <cjwylie@gmail.com>
Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>
Co-authored-by: Charles Smith <techdocsmith@gmail.com>
Co-authored-by: brian.le <brian.le@imply.io>
2022-09-06 14:42:18 -07:00
Vadim Ogievetsky 897689c03b
remove mentions of DruidQueryRel from docs (#13033)
* remove mentions of DruidQueryRel

* Update docs/querying/sql-translation.md

Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>

* Update docs/querying/sql-translation.md

Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>

Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>
2022-09-06 13:37:27 -07:00
Jill Osborne 7a1e1f88bb
Remove experimental note from stable features (#12973)
* Removed experimental note for features that are no longer experimental

* Updated native batch doc
2022-08-25 09:26:46 -07:00
Karan Kumar f7c6316992
Setting useNativeQueryExplain to true (#12936)
* Setting useNativeQueryExplain to true

* Update docs/querying/sql-query-context.md

Co-authored-by: Santosh Pingale <pingalesantosh@gmail.com>

* Fixing tests

* Fixing broken tests

Co-authored-by: Santosh Pingale <pingalesantosh@gmail.com>
2022-08-24 17:39:55 +05:30
Petar Petrov 6fec1d4c95
Add useNativeQueryExplain in sql query context documentation (#12924) (#12934)
Co-authored-by: Petar Petrov <petar.petrov@system73.com>
2022-08-22 16:31:15 +05:30
Clint Wylie f8097ccfaa
basic docs for nested column query functions (#12922)
* basic docs for nested column query functions
2022-08-19 17:12:19 -07:00
Clint Wylie 69fe1f04e5
document virtualColumns in native query documentation, fix some redirects (#12917)
* document virtualColumns in native query documentation, fix some redirects

* after all that, forgot to run spellcheck locally

* review stuff
2022-08-18 20:49:23 -07:00
Rohan Garg 5394838030
Enable conversion of join to filter by default (#12868) 2022-08-13 20:37:43 +05:30
Gian Merlino 01d555e47b
Adjust "in" filter null behavior to match "selector". (#12863)
* Adjust "in" filter null behavior to match "selector".

Now, both of them match numeric nulls if constructed with a "null" value.

This is consistent as far as native execution goes, but doesn't match
the behavior of SQL = and IN. So, to address that, this patch also
updates the docs to clarify that the native filters do match nulls.

This patch also updates the SQL docs to describe how Boolean logic is
handled in addition to how NULL values are handled.

Fixes #12856.

* Fix test.
2022-08-08 09:08:36 -07:00
Frank Chen a544aff761
Document missed simple granularities (#12768)
* Document missed simple granularities

* Update docs/querying/granularities.md

Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>

* Update docs/querying/granularities.md

Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>

Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>
2022-07-14 14:02:28 +08:00
Victoria Lim d8f8c56f94
Docs: Index page with all SQL functions (#12771)
* list of all functions

* add function names to spelling file
2022-07-14 09:59:55 +08:00
Gian Merlino 97207cdcc7
Automatic sizing for GroupBy dictionaries. (#12763)
* Automatic sizing for GroupBy dictionary sizes.

Merging and selector dictionary sizes currently both default to 100MB.
This is not optimal, because it can lead to OOM on small servers and
insufficient resource utilization on larger servers. It also invites
end users to try to tune it when queries run out of dictionary space,
which can make things worse if the end user sets it to too high.

So, this patch:

- Adds automatic tuning for selector and merge dictionaries. Selectors
  use up to 15% of the heap and merge buffers use up to 30% of the heap
  (aggregate across all queries).

- Updates out-of-memory error messages to emphasize enabling disk
  spilling vs. increasing memory parameters. With the memory parameters
  automatically sized, it is more likely that an end user will get
  benefit from enabling disk spilling.

- Removes the query context parameters that allow lowering of configured
  dictionary sizes. These complicate the calculation, and I don't see a
  reasonable use case for them.

* Adjust tests.

* Review adjustments.

* Additional comment.

* Remove unused import.
2022-07-11 08:20:50 -07:00
Jill Osborne 682ea7f32d
IMPLY-12348: Update description of UNION ALL in SQL syntax doc (#12710)
* IMPLY-12348: Updated description of UNION ALL

* Update docs/querying/sql.md

Co-authored-by: Charles Smith <techdocsmith@gmail.com>

* Update docs/querying/sql.md

Co-authored-by: Charles Smith <techdocsmith@gmail.com>

* Update sql.md

* Update docs/querying/sql.md

Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>

Co-authored-by: Charles Smith <techdocsmith@gmail.com>
Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>
2022-07-05 13:08:01 -07:00
Gian Merlino 0099940808
Add TIME_IN_INTERVAL SQL operator. (#12662)
* Add TIME_IN_INTERVAL SQL operator.

The operator is implemented as a convertlet rather than an
OperatorConversion, because this allows it to be equivalent to using
the >= and < operators directly.

* SqlParserPos cannot be null here.

* Remove unused import.

* Doc updates.

* Add words to dictionary.
2022-06-21 13:05:37 -07:00
Jill Osborne f050069767
Segments doc update (#12344)
* Corrected heading levels in segments doc

* IMPLY-18394: Updated Segments doc

* Update docs/design/segments.md

Co-authored-by: Charles Smith <techdocsmith@gmail.com>

* Update docs/design/segments.md

Co-authored-by: Charles Smith <techdocsmith@gmail.com>

* Update docs/design/segments.md

Co-authored-by: Charles Smith <techdocsmith@gmail.com>

* Update docs/design/segments.md

Co-authored-by: Charles Smith <techdocsmith@gmail.com>

* Update docs/design/segments.md

Co-authored-by: Charles Smith <techdocsmith@gmail.com>

* Update docs/design/segments.md

Co-authored-by: Charles Smith <techdocsmith@gmail.com>

* Update segments.md

* Updated links to changed headings in Segments doc

* Corrected spelling error

* Update segments.md

Incorporated suggestions from Paul Rogers.

* Update index.md

* Update segments.md

* Update segments.md

* Update segments.md

* Update compaction.md

* Update docs/design/segments.md

fix typo

* Update docs/ingestion/compaction.md

Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>

* Update docs/design/segments.md

Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>

* Update docs/design/segments.md

Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>

* Update docs/design/segments.md

Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>

* Update docs/design/segments.md

Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>

* Update docs/design/segments.md

Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>

* Update docs/design/segments.md

Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>

* Update docs/design/segments.md

Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>

* Update docs/design/segments.md

Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>

* Update docs/design/segments.md

Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>

* Update docs/design/segments.md

Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>

* Update docs/design/segments.md

Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>

Co-authored-by: Charles Smith <techdocsmith@gmail.com>
Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>
2022-06-16 13:25:17 -07:00
Jill Osborne 9c8e6bb000
Addition to Multitenancy considerations doc (#12567)
* Small addition to Multitenancy considerations doc

* Update docs/querying/multitenancy.md

Co-authored-by: Charles Smith <techdocsmith@gmail.com>

* Update multitenancy.md

Edit suggested by @kfaraz

Co-authored-by: Charles Smith <techdocsmith@gmail.com>
2022-06-02 10:32:14 -07:00
Gian Merlino 37853f8de4
ConcurrentGrouper: Add mergeThreadLocal option, fix bug around the switch to spilling. (#12513)
* ConcurrentGrouper: Add option to always slice up merge buffers thread-locally.

Normally, the ConcurrentGrouper shares merge buffers across processing
threads until spilling starts, and then switches to a thread-local model.
This minimizes memory use and reduces likelihood of spilling, which is
good, but it creates thread contention. The new mergeThreadLocal option
causes a query to start in thread-local mode immediately, and allows us
to experiment with the relative performance of the two modes.

* Fix grammar in docs.

* Fix race in ConcurrentGrouper.

* Fix issue with timeouts.

* Remove unused import.

* Add "tradeoff" to dictionary.
2022-05-21 10:28:54 -07:00
Gian Merlino 65a1375b67
SQL: Add is_active to sys.segments, update examples and docs. (#11550)
* SQL: Add is_active to sys.segments, update examples and docs.

is_active is short for:

  (is_published = 1 AND is_overshadowed = 0) OR is_realtime = 1

It's important because this represents "all the segments that should
be queryable, whether or not they actually are right now". Most of the
time, this is the set of segments that people will want to look at.

The web console already adds this filter to a lot of its queries,
proving its usefulness.

This patch also reworks the caveat at the bottom of the sys.segments
section, so its information is mixed into the description of each result
field. This should make it more likely for people to see the information.

* Wording updates.

* Adjustments for spellcheck.

* Adjust IT.
2022-05-19 14:23:28 -07:00