[SPARK-16625][SQL] General data types to be mapped to Oracle

## What changes were proposed in this pull request?

Spark will convert **BooleanType** to **BIT(1)**, **LongType** to **BIGINT**, **ByteType**  to **BYTE** when saving DataFrame to Oracle, but Oracle does not support BIT, BIGINT and BYTE types.

This PR is convert following _Spark Types_ to _Oracle types_ refer to [Oracle Developer's Guide](https://docs.oracle.com/cd/E19501-01/819-3659/gcmaz/)

Spark Type | Oracle
----|----
BooleanType | NUMBER(1)
IntegerType | NUMBER(10)
LongType | NUMBER(19)
FloatType | NUMBER(19, 4)
DoubleType | NUMBER(19, 4)
ByteType | NUMBER(3)
ShortType | NUMBER(5)

## How was this patch tested?

Add new tests in [JDBCSuite.scala](https://github.com/wangyum/spark/commit/22b0c2a4228cb8b5098ad741ddf4d1904e745ff6#diff-dc4b58851b084b274df6fe6b189db84d) and [OracleDialect.scala](https://github.com/wangyum/spark/commit/22b0c2a4228cb8b5098ad741ddf4d1904e745ff6#diff-5e0cadf526662f9281aa26315b3750ad)

Author: Yuming Wang <wgyumg@gmail.com>

Closes #14377 from wangyum/SPARK-16625.

1 files changed, 21 insertions, 0 deletions

diff --git a/sql/core/src/test/scala/org/apache/spark/sql/jdbc/JDBCSuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/jdbc/JDBCSuite.scala
index 995b1200a2..2d8ee338a9 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/jdbc/JDBCSuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/jdbc/JDBCSuite.scala
@@ -739,6 +739,27 @@ class JDBCSuite extends SparkFunSuite
       map(_.databaseTypeDefinition).get == "VARCHAR2(255)")
   }
 
+  test("SPARK-16625: General data types to be mapped to Oracle") {
+
+    def getJdbcType(dialect: JdbcDialect, dt: DataType): String = {
+      dialect.getJDBCType(dt).orElse(JdbcUtils.getCommonJDBCType(dt)).
+        map(_.databaseTypeDefinition).get
+    }
+
+    val oracleDialect = JdbcDialects.get("jdbc:oracle://127.0.0.1/db")
+    assert(getJdbcType(oracleDialect, BooleanType) == "NUMBER(1)")
+    assert(getJdbcType(oracleDialect, IntegerType) == "NUMBER(10)")
+    assert(getJdbcType(oracleDialect, LongType) == "NUMBER(19)")
+    assert(getJdbcType(oracleDialect, FloatType) == "NUMBER(19, 4)")
+    assert(getJdbcType(oracleDialect, DoubleType) == "NUMBER(19, 4)")
+    assert(getJdbcType(oracleDialect, ByteType) == "NUMBER(3)")
+    assert(getJdbcType(oracleDialect, ShortType) == "NUMBER(5)")
+    assert(getJdbcType(oracleDialect, StringType) == "VARCHAR2(255)")
+    assert(getJdbcType(oracleDialect, BinaryType) == "BLOB")
+    assert(getJdbcType(oracleDialect, DateType) == "DATE")
+    assert(getJdbcType(oracleDialect, TimestampType) == "TIMESTAMP")
+  }
+
   private def assertEmptyQuery(sqlString: String): Unit = {
     assert(sql(sqlString).collect().isEmpty)
   }