Implement the use of scalar functions inside aggregate functions.
This allows for complex expressions inside aggregations, with or without
GROUBY as well as with or without a HAVING clause. e.g.:
```
SELECT MAX(CASE WHEN a IS NULL then -1 ELSE abs(a * 10) + 1 END) AS max, b
FROM test
GROUP BY b
HAVING MAX(CASE WHEN a IS NULL then -1 ELSE abs(a * 10) + 1 END) > 5
```
Scalar functions are still not allowed for `KURTOSIS` and `SKEWNESS` as
this is currently not implemented on the ElasticSearch side.
Fixes: #29980Fixes: #36865Fixes: #37271
(cherry picked from commit 506d1beea7abb2b45de793bba2e349090a78f2f9)
Add a section to point out that when ordering by an aggregate
only plain aggregate functions are allowed, no scalars/operators
can be used on top of them.
Fixes: #52204
(cherry picked from commit 78a1185549ff7f3229fd2d036567eb2a4f2cf230)
Previously, if YEAR() was used as and ORDER BY argument without being
wrapped with another scalar (e.g. YEAR(birth_date) + 10), no script
ordering was used but instead the underlying field (e.g. birth_date)
was used instead as a performance optimisation. This works correctly if
YEAR() is the only ORDER BY arg but if further args are used as tie
breakers for the ordering wrong results are produced. This is because
2 rows with the different birth_date but on the same year are not tied
as the underlying ordering is on birth_date and not on the
YEAR(birth_date), and the following ORDER BY args are ignored.
Remove this optimisation for YEAR() to avoid incorrect results in
such cases.
As a consequence another bug is revealed: scalar functions on top
of nested fields produce scripted sorting/filtering which is not yet
supported. In such cases no error was thrown but instead all values for
such nested fields were null and were passed to the script implementing
the sorting/filtering, producing incorrect results.
Detect such cases and throw a validation exception.
Fixes: #51224
(cherry picked from commit f41efd6753dc3650a7eabb3e07b02b3b32c5704c)
* Switch from using docvalue_fields to extracting values from _source
where applicable. Doing this means parsing the _source and handling the
numbers parsing just like Elasticsearch is doing it when it's indexing
a document.
* This also introduces a minor limitation: aliases type of fields that
are NOT part of a tree of sub-fields will not be able to be retrieved
anymore. field_caps API doesn't shed any light into a field being an
alias or not and at _source parsing time there is no way to know if a
root field is an alias or not. Fields of the type "a.b.c.alias" can be
extracted from docvalue_fields, only if the field they point to can be
extracted from docvalue_fields. Also, not all fields in a hierarchy of
fields can be evaluated to being an alias.
(cherry picked from commit 8bf8a055e38f00df5f49c8d97f632f69d6e00c2c)
To be consistent with the `search.max_buckets` default setting,
set the hard limit of the PriorityQueue used for in memory sorting,
when sorting on an aggregate function, to 10000.
Fixes: #43168
(cherry picked from commit 079e012fdea68ea0a7daae078359495047e9c407)
Adds an initial limited implementations of geo features to SQL. This implementation is based on the [OpenGIS® Implementation Standard for Geographic information - Simple feature access](http://www.opengeospatial.org/standards/sfs), which is the current standard for GIS system implementation. This effort is concentrate on SQL option AKA ISO 19125-2.
Queries that are supported as a result of this initial implementation
Metadata commands
- `DESCRIBE table` - returns the correct column types `GEOMETRY` for geo shapes and geo points.
- `SHOW FUNCTIONS` - returns a list that includes supported `ST_` functions
- `SYS TYPES` and `SYS COLUMNS` display correct types `GEO_SHAPE` and `GEO_POINT` for geo shapes and geo points accordingly.
Returning geoshapes and geopoints from elasticsearch
- `SELECT geom FROM table` - returns the geoshapes and geo_points as libs/geo objects in JDBC or as WKT strings in console.
- `SELECT ST_AsWKT(geom) FROM table;` and `SELECT ST_AsText(geom) FROM table;`- returns the geoshapes ang geopoints in their WKT representation;
Using geopoints to elasticsearch
- The following functions will be supported for geopoints in queries, sorting and aggregations: `ST_GeomFromText`, `ST_X`, `ST_Y`, `ST_Z`, `ST_GeometryType`, and `ST_Distance`. In most cases when used in queries, sorting and aggregations, these function are translated into script. These functions can be used in the SELECT clause for both geopoints and geoshapes.
- `SELECT * FROM table WHERE ST_Distance(ST_GeomFromText(POINT(1 2), point) < 10;` - returns all records for which `point` is located within 10m from the `POINT(1 2)`. In this case the WHERE clause is translated into a range query.
Limitations:
Geoshapes cannot be used in queries, sorting and aggregations as part of this initial effort. In order to fully take advantage of geoshapes we would need to have access to geoshape doc values, which is coming in #37206. `ST_Z` cannot be used on geopoints in queries, sorting and aggregations since we don't store altitude in geo_point doc values.
Relates to #29872
Backport of #42031
The CircuitBreaker was introduced as means of preventing a
`StackOverflowException` during the build of the AST by the parser.
The ANTLR4 grammar causes a weird behaviour for a Parser Listener.
The `enterEveryRule()` method is often called with a different parsing
context than the respective `exitEveryRule()`. This makes it difficult
to keep track of the tree's depth, and a custom Map was used as an
attempt of matching the contextes as they are encounter during `enter`
and during `exit` of the rules.
This approach had 2 important drawbacks:
1. It's hard to maintain this custom Map as the grammar changes.
2. The CircuitBreaker could often lead to false positives which caused
valid queries to return an Exception and prevent them from executing.
So, this removes completely the CircuitBreaker which is replaced be
a simple handling of the `StackOverflowException`
Fixes: #41471
(cherry picked from commit 1559a8e2dbd729138b52e89b7e80264c9f4ad1e7)
Support ANSI SQL's TIME type by introductin a runtime-only
ES SQL time type.
Closes: #38174
(cherry picked from commit 046ccd4cf0a251b2a3ddff6b072ab539a6711900)
To avoid having to specify each spec by hand (which can miss specs to be
added), the test infrastructure now performs classpath discovery so that
each spec added, is automatically considered.
Relates #40358
(cherry picked from commit d0f60b4425c731509aa8ca765d55f563f866ef90)
For cases where fields can have multi values, allow the behavior to be
customized through a dedicated configuration field.
By default this will be enabled on the drivers so that existing datasets
work instead of throwing an exception.
For regular SQL usage, the behavior is false so that the user is aware
of the underlying data.
Fix#39700
(cherry picked from commit 2b351571961f172fd59290ee079126bbd081ceaf)
* SYS COLUMNS will skip UNSUPPORTED field types in ODBC and JDBC, as well.
NESTED and OBJECT types were already skipped in ODBC mode, now they are
skipped in JDBC mode, as well.
(cherry picked from commit 9e0df64b2d36c9069dfa506570468f0522c86417)
Introduce client-side sorting of groups based on aggregate
functions. To allow this, the Analyzer has been extended to push down
to underlying Aggregate, aggregate function and the Querier has been
extended to identify the case and consume the results in order and sort
them based on the given columns.
The underlying QueryContainer has been slightly modified to allow a view
of the underlying values being extracted as the columns used for sorting
might not be requested by the user.
The PR also adds minor tweaks, mainly related to tree output.
Close#35118
Currently aggregate functions can operate only directly on fields.
They cannot be used on top of scalar functions as painless scripting
is currently not supported.
FIRST and LAST can be used with one argument and work similarly to MIN
and MAX but they are implemented using a Top Hits aggregation and
therefore can also operate on keyword fields. When a second argument is
provided then they return the first/last value of the first arg when its
values are ordered ascending/descending (respectively) by the values of
the second argument. Currently because of the usage of a Top Hits
aggregation FIRST and LAST cannot be used in the HAVING clause of a
GROUP BY query to filter on the results of the aggregation.
Closes: #35639
* Added Limitations page
* Made the aggregations page follow the common template for functions
* Modified all tables to have the first row's cells content centered
* Polishing in other various sections
Marios Trivyzas
Marios Trivyzas
Bogdan Pintea
Andrei Stefan
Igor Motov
James Rodewig
Costin Leau