[SPARK-19359][SQL] Revert Clear useless path after rename a partition with upper-case by HiveExternalCatalog

### What changes were proposed in this pull request?

This PR is to revert the changes made in https://github.com/apache/spark/pull/16700. It could cause the data loss after partition rename, because we have a bug in the file renaming.

Not all the OSs have the same behaviors. For example, on mac OS, if we renaming a path from `.../tbl/a=5/b=6` to `.../tbl/A=5/B=6`. The result is `.../tbl/a=5/B=6`. The expected result is `.../tbl/A=5/B=6`. Thus, renaming on mac OS is not recursive. However, the systems used in Jenkin does not have such an issue. Although this PR is not the root cause, it exposes an existing issue on the code `tablePath.getFileSystem(hadoopConf).rename(wrongPath, rightPath)`

---

Hive metastore is not case preserving and keep partition columns with lower case names.

If SparkSQL create a table with upper-case partion name use HiveExternalCatalog, when we rename partition, it first call the HiveClient to renamePartition, which will create a new lower case partition path, then SparkSql rename the lower case path to the upper-case.

while if the renamed partition contains more than one depth partition ,e.g. A=1/B=2, hive renamePartition change to a=1/b=2, then SparkSql rename it to A=1/B=2, but the a=1 still exists in the filesystem, we should also delete it.

### How was this patch tested?
N/A

Author: gatorsmile <gatorsmile@gmail.com>

Closes #16728 from gatorsmile/revert-pr-16700.

2 files changed, 0 insertions, 71 deletions

diff --git a/sql/hive/src/main/scala/org/apache/spark/sql/hive/HiveExternalCatalog.scala b/sql/hive/src/main/scala/org/apache/spark/sql/hive/HiveExternalCatalog.scala
index 5be991b471..208c8c9d5d 100644
--- a/sql/hive/src/main/scala/org/apache/spark/sql/hive/HiveExternalCatalog.scala
+++ b/sql/hive/src/main/scala/org/apache/spark/sql/hive/HiveExternalCatalog.scala
@@ -839,26 +839,6 @@ private[spark] class HiveExternalCatalog(conf: SparkConf, hadoopConf: Configurat
     spec.map { case (k, v) => partCols.find(_.equalsIgnoreCase(k)).get -> v }
   }
 
-
-  /**
-   * The partition path created by Hive is in lowercase, while Spark SQL will
-   * rename it with the partition name in partitionColumnNames, and this function
-   * returns the extra lowercase path created by Hive, and then we can delete it.
-   * e.g. /path/A=1/B=2/C=3 is changed to /path/A=4/B=5/C=6, this function returns
-   * /path/a=4
-   */
-  def getExtraPartPathCreatedByHive(
-      spec: TablePartitionSpec,
-      partitionColumnNames: Seq[String],
-      tablePath: Path): Path = {
-    val partColumnNames = partitionColumnNames
-      .take(partitionColumnNames.indexWhere(col => col.toLowerCase != col) + 1)
-      .map(_.toLowerCase)
-
-    ExternalCatalogUtils.generatePartitionPath(lowerCasePartitionSpec(spec),
-      partColumnNames, tablePath)
-  }
-
   override def createPartitions(
       db: String,
       table: String,
@@ -919,21 +899,6 @@ private[spark] class HiveExternalCatalog(conf: SparkConf, hadoopConf: Configurat
           spec, partitionColumnNames, tablePath)
         try {
           tablePath.getFileSystem(hadoopConf).rename(wrongPath, rightPath)
-
-          // If the newSpec contains more than one depth partition, FileSystem.rename just deletes
-          // the leaf(i.e. wrongPath), we should check if wrongPath's parents need to be deleted.
-          // For example, give a newSpec 'A=1/B=2', after calling Hive's client.renamePartitions,
-          // the location path in FileSystem is changed to 'a=1/b=2', which is wrongPath, then
-          // although we renamed it to 'A=1/B=2', 'a=1/b=2' in FileSystem is deleted, but 'a=1'
-          // is still exists, which we also need to delete
-          val delHivePartPathAfterRename = getExtraPartPathCreatedByHive(
-            spec,
-            partitionColumnNames,
-            tablePath)
-
-          if (delHivePartPathAfterRename != wrongPath) {
-            tablePath.getFileSystem(hadoopConf).delete(delHivePartPathAfterRename, true)
-          }
         } catch {
           case e: IOException => throw new SparkException(
             s"Unable to rename partition path from $wrongPath to $rightPath", e)
diff --git a/sql/hive/src/test/scala/org/apache/spark/sql/hive/PartitionProviderCompatibilitySuite.scala b/sql/hive/src/test/scala/org/apache/spark/sql/hive/PartitionProviderCompatibilitySuite.scala
index 1214a92b76..dca207a72d 100644
--- a/sql/hive/src/test/scala/org/apache/spark/sql/hive/PartitionProviderCompatibilitySuite.scala
+++ b/sql/hive/src/test/scala/org/apache/spark/sql/hive/PartitionProviderCompatibilitySuite.scala
@@ -19,11 +19,8 @@ package org.apache.spark.sql.hive
 
 import java.io.File
 
-import org.apache.hadoop.fs.Path
-
 import org.apache.spark.metrics.source.HiveCatalogMetrics
 import org.apache.spark.sql.{AnalysisException, QueryTest}
-import org.apache.spark.sql.catalyst.TableIdentifier
 import org.apache.spark.sql.hive.test.TestHiveSingleton
 import org.apache.spark.sql.internal.SQLConf
 import org.apache.spark.sql.test.SQLTestUtils
@@ -484,37 +481,4 @@ class PartitionProviderCompatibilitySuite
       assert(spark.sql("show partitions test").count() == 5)
     }
   }
-
-  test("partition path created by Hive should be deleted after renamePartitions with upper-case") {
-    withTable("t", "t1", "t2") {
-      Seq((1, 2, 3)).toDF("id", "A", "B").write.partitionBy("A", "B").saveAsTable("t")
-      spark.sql("alter table t partition(A=2, B=3) rename to partition(A=4, B=5)")
-
-      var table = spark.sessionState.catalog.getTableMetadata(TableIdentifier("t"))
-      var extraHivePath = new Path(table.location + "/a=4")
-      assert(!extraHivePath.getFileSystem(spark.sessionState.newHadoopConf())
-        .exists(extraHivePath), "partition path created by Hive should be deleted " +
-        "after renamePartitions with upper-case")
-
-      Seq((1, 2, 3, 4)).toDF("id", "A", "B", "C").write.partitionBy("A", "B", "C").saveAsTable("t1")
-      spark.sql("alter table t1 partition(A=2, B=3, C=4) rename to partition(A=5, B=6, C=7)")
-      table = spark.sessionState.catalog.getTableMetadata(TableIdentifier("t1"))
-      extraHivePath = new Path(table.location + "/a=5")
-      assert(!extraHivePath.getFileSystem(spark.sessionState.newHadoopConf())
-        .exists(extraHivePath), "partition path created by Hive should be deleted " +
-        "after renamePartitions with upper-case")
-
-      Seq((1, 2, 3, 4)).toDF("id", "a", "B", "C").write.partitionBy("a", "B", "C").saveAsTable("t2")
-      spark.sql("alter table t2 partition(a=2, B=3, C=4) rename to partition(a=4, B=5, C=6)")
-      table = spark.sessionState.catalog.getTableMetadata(TableIdentifier("t2"))
-      val partPath = new Path(table.location + "/a=4")
-      assert(partPath.getFileSystem(spark.sessionState.newHadoopConf())
-        .exists(partPath), "partition path of lower-case partition name should not be deleted")
-
-      extraHivePath = new Path(table.location + "/a=4/b=5")
-      assert(!extraHivePath.getFileSystem(spark.sessionState.newHadoopConf())
-        .exists(extraHivePath), "partition path created by Hive should be deleted " +
-        "after renamePartitions with upper-case")
-    }
-  }
 }