6ed2dfbba1
### What changes were proposed in this pull request?
Add a new logical node AggregateWithHaving, and the parser should create this plan for HAVING. The analyzer resolves it to Filter(..., Aggregate(...)).
### Why are the changes needed?
The SQL parser in Spark creates Filter(..., Aggregate(...)) for the HAVING query, and Spark has a special analyzer rule ResolveAggregateFunctions to resolve the aggregate functions and grouping columns in the Filter operator.
It works for simple cases in a very tricky way as it relies on rule execution order:
1. Rule ResolveReferences hits the Aggregate operator and resolves attributes inside aggregate functions, but the function itself is still unresolved as it's an UnresolvedFunction. This stops resolving the Filter operator as the child Aggrege operator is still unresolved.
2. Rule ResolveFunctions resolves UnresolvedFunction. This makes the Aggrege operator resolved.
3. Rule ResolveAggregateFunctions resolves the Filter operator if its child is a resolved Aggregate. This rule can correctly resolve the grouping columns.
In the example query, I put a CAST, which needs to be resolved by rule ResolveTimeZone, which runs after ResolveAggregateFunctions. This breaks step 3 as the Aggregate operator is unresolved at that time. Then the analyzer starts next round and the Filter operator is resolved by ResolveReferences, which wrongly resolves the grouping columns.
See the demo below:
```
SELECT SUM(a) AS b, '2020-01-01' AS fake FROM VALUES (1, 10), (2, 20) AS T(a, b) GROUP BY b HAVING b > 10
```
The query's result is
```
+---+----------+
| b| fake|
+---+----------+
| 2|2020-01-01|
+---+----------+
```
But if we add CAST, it will return an empty result.
```
SELECT SUM(a) AS b, CAST('2020-01-01' AS DATE) AS fake FROM VALUES (1, 10), (2, 20) AS T(a, b) GROUP BY b HAVING b > 10
```
### Does this PR introduce any user-facing change?
Yes, bug fix for cast in having aggregate expressions.
### How was this patch tested?
New UT added.
Closes #28294 from xuanyuanking/SPARK-31519.
Authored-by: Yuanjian Li <xyliyuanjian@gmail.com>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
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|---|---|---|
| .. | ||
| catalyst | ||
| core | ||
| hive | ||
| hive-thriftserver | ||
| create-docs.sh | ||
| gen-sql-api-docs.py | ||
| gen-sql-config-docs.py | ||
| gen-sql-functions-docs.py | ||
| mkdocs.yml | ||
| README.md | ||
Spark SQL
This module provides support for executing relational queries expressed in either SQL or the DataFrame/Dataset API.
Spark SQL is broken up into four subprojects:
- Catalyst (sql/catalyst) - An implementation-agnostic framework for manipulating trees of relational operators and expressions.
- Execution (sql/core) - A query planner / execution engine for translating Catalyst's logical query plans into Spark RDDs. This component also includes a new public interface, SQLContext, that allows users to execute SQL or LINQ statements against existing RDDs and Parquet files.
- Hive Support (sql/hive) - Includes extensions that allow users to write queries using a subset of HiveQL and access data from a Hive Metastore using Hive SerDes. There are also wrappers that allow users to run queries that include Hive UDFs, UDAFs, and UDTFs.
- HiveServer and CLI support (sql/hive-thriftserver) - Includes support for the SQL CLI (bin/spark-sql) and a HiveServer2 (for JDBC/ODBC) compatible server.
Running ./sql/create-docs.sh generates SQL documentation for built-in functions under sql/site, and SQL configuration documentation that gets included as part of configuration.md in the main docs directory.