* Refresh query docs.
Larger changes:
- New doc: querying/datasource.md describes the various kinds of
datasources you can use, and has examples for both SQL and native.
- New doc: querying/query-execution.md describes how native queries
are executed at a high level. It doesn't go into the details of specific
query engines or how queries run at a per-segment level. But I think it
would be good to add or link that content here in the future.
- Refreshed doc: querying/sql.md updated to refer to joins, reformatted
a bit, added a new "Query translation" section that explains how
queries are translated from SQL to native, and removed configuration
details (moved to configuration/index.md).
- Refreshed doc: querying/joins.md updated to refer to join datasources.
Smaller changes:
- Add helpful banners to the top of query documentation pages telling
people whether a given page describes SQL, native, or both.
- Add SQL metrics to operations/metrics.md.
- Add some color and cross-links in various places.
- Add native query component docs to the sidebar, and renamed them so
they look nicer.
- Remove Select query from the sidebar.
- Fix Broker SQL configs in configuration/index.md. Remove them from
querying/sql.md.
- Combined querying/searchquery.md and querying/searchqueryspec.md.
* Updates.
* Fix numbering.
* Fix glitches.
* Add new words to spellcheck file.
* Assorted changes.
* Further adjustments.
* Add missing punctuation.
* SQL support for joins on subqueries.
Changes to SQL module:
- DruidJoinRule: Allow joins on subqueries (left/right are no longer
required to be scans or mappings).
- DruidJoinRel: Add cost estimation code for joins on subqueries.
- DruidSemiJoinRule, DruidSemiJoinRel: Removed, since DruidJoinRule can
handle this case now.
- DruidRel: Remove Nullable annotation from toDruidQuery, because
it is no longer needed (it was used by DruidSemiJoinRel).
- Update Rules constants to reflect new rules available in our current
version of Calcite. Some of these are useful for optimizing joins on
subqueries.
- Rework cost estimation to be in terms of cost per row, and place all
relevant constants in CostEstimates.
Other changes:
- RowBasedColumnSelectorFactory: Don't set hasMultipleValues. The lack
of isComplete is enough to let callers know that columns might have
multiple values, and explicitly setting it to true causes
ExpressionSelectors to think it definitely has multiple values, and
treat the inputs as arrays. This behavior interfered with some of the
new tests that involved queries on lookups.
- QueryContexts: Add maxSubqueryRows parameter, and use it in druid-sql
tests.
* Fixes for tests.
* Adjustments.
* Match GREATEST/LEAST function behavior
Change the behavior of the GREATEST / LEAST functions to be similar to
how it is implemented in other databases (as functions instead of
aggregators). The GREATEST/LEAST functions are not in the SQL standard,
but users will expect behavior similar to what other databases provide.
* Match postgres behavior & handle more SQL types
* Fix imports
* Add SQL GROUPING SETS support.
Built on top of the subtotalsSpec feature in the groupBy query. This also involves
two changes to subtotalsSpec:
- Alter behavior so limitSpec is applied after subtotalsSpec, rather than applied to
each grouping set. This is more in line with SQL standard behavior. I think it is okay
to make this change, since the old behavior was not documented, so users should
hopefully not be depending on it.
- Fix a bug where virtual columns were included in the subtotal queries, but they
should not have been.
Also fixes two bugs in query equality checking:
- BaseQuery: Use getDuration() instead of "duration" in equals and hashCode, since the
latter is lazily initialized and might be null in one query but not the other.
- GroupByQuery: Include subtotalsSpec in equals and hashCode.
* Fix bugs.
* Fix tests.
* PR updates.
* Grouping class hygiene.
* implement shell for greatest sql aggregator with hardcoded long values
* implement functional long greatest aggregator for direct access columns
* implement greatest & least sql aggregators for long & double types using abstract base class
* add javadocs, unit tests & handling for floats for greatest/least postaggregations
* minor checkstyle fix
* improve naming for the test cases
* make inner class static
* remove blank lines to retest travis build
* change trivial text to rerun travis build
* implement suggested updates for greatest/least sql aggs & fix checkstyle issues
* fix stale comments in greatest/least sql aggs abstract base
* Update sql.md
* improve sql function definitions for greatest/least sql aggs
* add more tests for greatest/least sql aggs
* add tests to cover invalid greatest/least sql expressions
* rename & reorder greatest least sql tests
* null handling for numeric first/last aggregators, refactor to not extend nullable numeric agg since they are complex typed aggs
* initially null or not based on config
* review stuff, make string first/last consistent with null handling of numeric columns, more tests
* docs
* handle nil selectors, revert to primitive first/last types so groupby v1 works...
* SQL: EARLIEST, LATEST aggregators.
I chose these names instead of FIRST, LAST because those are already
reserved functions in Calcite that mean something different. I think
these are also better names anyway.
* Finalify.
* SQL updates.
* Adjust aggregator calls.
* Validations, test updates.
* Review docs.
* Add group_id to overlord tasks API and sys.tasks table
* adjust test
* modify docs
* Make groupId nullable
* fix integration test
* fix toString
* Remove groupId from TaskInfo
* Modify docs and tests
* modify TaskMonitorTest
Gian Merlino
Chi Cao Minh
Clint Wylie
Maytas Monsereenusorn
Aditya
Jonathan Wei
Surekha