fix empty string location of database

Author: windpiger

sql/core/src/main/scala/org/apache/spark/sql/internal/SharedState.scala

@@ -90,10 +90,8 @@ private[sql] class SharedState(val sparkContext: SparkContext) extends Logging {
 
   // Create the default database if it doesn't exist.
   {
-    // default database set to empty string,
-    // when reload from metastore using warehouse path to replace it
     val defaultDbDefinition = CatalogDatabase(
-      SessionCatalog.DEFAULT_DATABASE, "default database", "", Map())
+      SessionCatalog.DEFAULT_DATABASE, "default database", warehousePath, Map())
     // Initialize default database if it doesn't exist
     if (!externalCatalog.databaseExists(SessionCatalog.DEFAULT_DATABASE)) {
       // There may be another Spark application creating default database at the same time, here we

sql/hive/src/main/scala/org/apache/spark/sql/hive/client/HiveClientImpl.scala

@@ -313,12 +313,11 @@ private[hive] class HiveClientImpl(
   override def createDatabase(
       database: CatalogDatabase,
       ignoreIfExists: Boolean): Unit = withHiveState {
-    // default database's location always use the warehouse path, here set to emtpy string
     client.createDatabase(
       new HiveDatabase(
         database.name,
         database.description,
-        if (database.name == SessionCatalog.DEFAULT_DATABASE) "" else database.locationUri,
+        database.locationUri,
         Option(database.properties).map(_.asJava).orNull),
         ignoreIfExists)
   }