modify some comment

windpiger · windpiger · commit b4c55d6f39e8 · 2017-02-24T20:49:58.000+08:00
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/catalog/SessionCatalog.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/catalog/SessionCatalog.scala
@@ -249,6 +249,10 @@ class SessionCatalog(
   /**
    * Create a metastore table in the database specified in `tableDefinition`.
    * If no such database is specified, create it in the current database.
+   * suggestIgnoreIfPathExists suggest whether should check if the path of table
+   * exists when ignoreIfExists is false, if it is false, it will only check the
+   * path of a managed table, if it is true, it will not do the check for all
+   * type tables.
    */
   def createTable(
     tableDefinition: CatalogTable,
diff --git a/sql/core/src/main/scala/org/apache/spark/sql/execution/command/createDataSourceTables.scala b/sql/core/src/main/scala/org/apache/spark/sql/execution/command/createDataSourceTables.scala
@@ -158,6 +158,8 @@ case class CreateDataSourceTableAsSelectCommand(
         // the schema of df). It is important since the nullability may be changed by the relation
         // provider (for example, see org.apache.spark.sql.parquet.DefaultSource).
         schema = result.schema)
+      // the path of the table has been created above before create table, we should not
+      // check if the path existes, so suggestIgnoreIfPathExists set to true .
       sessionState.catalog.createTable(newTable, ignoreIfExists = false,
         suggestIgnoreIfPathExists = true)
 
diff --git a/sql/hive/src/main/scala/org/apache/spark/sql/hive/execution/CreateHiveTableAsSelectCommand.scala b/sql/hive/src/main/scala/org/apache/spark/sql/hive/execution/CreateHiveTableAsSelectCommand.scala
@@ -19,11 +19,9 @@ package org.apache.spark.sql.hive.execution
 
 import scala.util.control.NonFatal
 
-import org.apache.hadoop.fs.Path
-
 import org.apache.spark.sql.{AnalysisException, Row, SaveMode, SparkSession}
 import org.apache.spark.sql.catalyst.analysis.UnresolvedRelation
-import org.apache.spark.sql.catalyst.catalog.{CatalogTable, CatalogTableType}
+import org.apache.spark.sql.catalyst.catalog.CatalogTable
 import org.apache.spark.sql.catalyst.plans.logical.{InsertIntoTable, LogicalPlan}
 import org.apache.spark.sql.execution.command.RunnableCommand
 
@@ -70,9 +68,9 @@ case class CreateHiveTableAsSelectCommand(
       // add the relation into catalog, just in case of failure occurs while data
       // processing.
       assert(tableDesc.schema.isEmpty)
-
       sparkSession.sessionState.catalog.createTable(
         tableDesc.copy(schema = query.schema), ignoreIfExists = false)
+
       try {
         sparkSession.sessionState.executePlan(
           InsertIntoTable(
