da72b87374
### What changes were proposed in this pull request?
In this PR, we suppose to narrow the use cases of the char/varchar data types, of which are invalid now or later
### Why are the changes needed?
1. udf
```scala
scala> spark.udf.register("abcd", () => "12345", org.apache.spark.sql.types.VarcharType(2))
scala> spark.sql("select abcd()").show
scala.MatchError: CharType(2) (of class org.apache.spark.sql.types.VarcharType)
at org.apache.spark.sql.catalyst.encoders.RowEncoder$.externalDataTypeFor(RowEncoder.scala:215)
at org.apache.spark.sql.catalyst.encoders.RowEncoder$.externalDataTypeForInput(RowEncoder.scala:212)
at org.apache.spark.sql.catalyst.expressions.objects.ValidateExternalType.<init>(objects.scala:1741)
at org.apache.spark.sql.catalyst.encoders.RowEncoder$.$anonfun$serializerFor$3(RowEncoder.scala:175)
at scala.collection.TraversableLike.$anonfun$flatMap$1(TraversableLike.scala:245)
at scala.collection.IndexedSeqOptimized.foreach(IndexedSeqOptimized.scala:36)
at scala.collection.IndexedSeqOptimized.foreach$(IndexedSeqOptimized.scala:33)
at scala.collection.mutable.ArrayOps$ofRef.foreach(ArrayOps.scala:198)
at scala.collection.TraversableLike.flatMap(TraversableLike.scala:245)
at scala.collection.TraversableLike.flatMap$(TraversableLike.scala:242)
at scala.collection.mutable.ArrayOps$ofRef.flatMap(ArrayOps.scala:198)
at org.apache.spark.sql.catalyst.encoders.RowEncoder$.serializerFor(RowEncoder.scala:171)
at org.apache.spark.sql.catalyst.encoders.RowEncoder$.apply(RowEncoder.scala:66)
at org.apache.spark.sql.Dataset$.$anonfun$ofRows$2(Dataset.scala:99)
at org.apache.spark.sql.SparkSession.withActive(SparkSession.scala:768)
at org.apache.spark.sql.Dataset$.ofRows(Dataset.scala:96)
at org.apache.spark.sql.SparkSession.$anonfun$sql$1(SparkSession.scala:611)
at org.apache.spark.sql.SparkSession.withActive(SparkSession.scala:768)
at org.apache.spark.sql.SparkSession.sql(SparkSession.scala:606)
... 47 elided
```
2. spark.createDataframe
```
scala> spark.createDataFrame(spark.read.text("README.md").rdd, new org.apache.spark.sql.types.StructType().add("c", "char(1)")).show
+--------------------+
| c|
+--------------------+
| # Apache Spark|
| |
|Spark is a unifie...|
|high-level APIs i...|
|supports general ...|
|rich set of highe...|
|MLlib for machine...|
|and Structured St...|
| |
|<https://spark.ap...|
| |
|[![Jenkins Build]...|
|[![AppVeyor Build...|
|[![PySpark Covera...|
| |
| |
```
3. reader.schema
```
scala> spark.read.schema("a varchar(2)").text("./README.md").show(100)
+--------------------+
| a|
+--------------------+
| # Apache Spark|
| |
|Spark is a unifie...|
|high-level APIs i...|
|supports general ...|
```
4. etc
### Does this PR introduce _any_ user-facing change?
NO, we intend to avoid protentical breaking change
### How was this patch tested?
new tests
Closes #30586 from yaooqinn/SPARK-33641.
Authored-by: Kent Yao <yaooqinn@hotmail.com>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
|
||
|---|---|---|
| .. | ||
| 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.