Github user xuchuanyin commented on a diff in the pull request:
https://github.com/apache/carbondata/pull/2374#discussion_r196627213
--- Diff:
integration/spark2/src/main/scala/org/apache/spark/sql/execution/command/management/CarbonAddSegmentCommand.scala
---
@@ -0,0 +1,135 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql.execution.command.management
+
+import java.util.UUID
+
+import org.apache.spark.sql.{CarbonEnv, Row, SparkSession}
+import org.apache.spark.sql.catalyst.analysis.NoSuchTableException
+import org.apache.spark.sql.execution.command.AtomicRunnableCommand
+import org.apache.spark.sql.hive.CarbonRelation
+import org.apache.spark.util.FileUtils
+
+import org.apache.carbondata.common.logging.LogServiceFactory
+import org.apache.carbondata.core.datamap.status.DataMapStatusManager
+import org.apache.carbondata.core.metadata.schema.table.CarbonTable
+import org.apache.carbondata.core.mutate.CarbonUpdateUtil
+import org.apache.carbondata.core.statusmanager.{FileFormat,
LoadMetadataDetails, SegmentStatus, SegmentStatusManager}
+import org.apache.carbondata.core.util.CarbonUtil
+import org.apache.carbondata.core.util.path.CarbonTablePath
+import org.apache.carbondata.events.{OperationContext,
OperationListenerBus}
+import
org.apache.carbondata.processing.loading.events.LoadEvents.LoadMetadataEvent
+import
org.apache.carbondata.processing.loading.model.{CarbonDataLoadSchema,
CarbonLoadModel}
+import org.apache.carbondata.processing.util.CarbonLoaderUtil
+
+/**
+ * support `alter table tableName add segment location 'path'` command.
+ * It will create a segment and map the path of datafile to segment's
storage
+ */
+case class CarbonAddSegmentCommand(
+ dbNameOp: Option[String],
+ tableName: String,
+ filePathFromUser: String,
+ var operationContext: OperationContext = new OperationContext) extends
AtomicRunnableCommand {
+ private val LOGGER =
LogServiceFactory.getLogService(this.getClass.getName)
+ var carbonTable: CarbonTable = _
+
+ override def processMetadata(sparkSession: SparkSession): Seq[Row] = {
+ val dbName = CarbonEnv.getDatabaseName(dbNameOp)(sparkSession)
+ carbonTable = {
+ val relation = CarbonEnv.getInstance(sparkSession).carbonMetastore
+ .lookupRelation(Option(dbName),
tableName)(sparkSession).asInstanceOf[CarbonRelation]
+ if (relation == null) {
+ LOGGER.error(s"Add segment failed due to table $dbName.$tableName
not found")
+ throw new NoSuchTableException(dbName, tableName)
+ }
+ relation.carbonTable
+ }
+
+ if (carbonTable.isHivePartitionTable) {
+ LOGGER.error("Ignore hive partition table for now")
+ }
+
+ operationContext.setProperty("isOverwrite", false)
+ if (CarbonUtil.hasAggregationDataMap(carbonTable)) {
+ val loadMetadataEvent = new LoadMetadataEvent(carbonTable, false)
+ OperationListenerBus.getInstance().fireEvent(loadMetadataEvent,
operationContext)
+ }
+ Seq.empty
+ }
+
+ // will just mapping external files to segment metadata
+ override def processData(sparkSession: SparkSession): Seq[Row] = {
--- End diff --
In my opinion, creating the segment and updating the tablestatus both
belong to `processData`. And in other command such as LoadData, these operation
are in `processData` too.
---
