public Partition alterPartition()

in standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/HiveAlterHandler.java [545:794]


  public Partition alterPartition(RawStore msdb, Warehouse wh, String catName, String dbname,
      String name, List<String> part_vals, final Partition new_part,
      EnvironmentContext environmentContext, IHMSHandler handler, String validWriteIds)
      throws InvalidOperationException, InvalidObjectException, AlreadyExistsException, MetaException, NoSuchObjectException {
    boolean success = false;
    Partition oldPart;
    List<TransactionalMetaStoreEventListener> transactionalListeners = null;
    if (handler != null) {
      transactionalListeners = handler.getTransactionalListeners();
    }

    // Set DDL time to now if not specified
    if (new_part.getParameters() == null ||
        new_part.getParameters().get(hive_metastoreConstants.DDL_TIME) == null ||
        Integer.parseInt(new_part.getParameters().get(hive_metastoreConstants.DDL_TIME)) == 0) {
      new_part.putToParameters(hive_metastoreConstants.DDL_TIME, Long.toString(System
          .currentTimeMillis() / 1000));
    }

    //alter partition
    if (part_vals == null || part_vals.size() == 0) {
      try {
        msdb.openTransaction();

        Table tbl = msdb.getTable(catName, dbname, name, null);
        if (tbl == null) {
          throw new InvalidObjectException(
              "Unable to alter partition because table or database does not exist.");
        }
        oldPart = msdb.getPartition(catName, dbname, name, new_part.getValues());
        if (MetaStoreServerUtils.requireCalStats(oldPart, new_part, tbl, environmentContext)) {
          // if stats are same, no need to update
          if (MetaStoreServerUtils.isFastStatsSame(oldPart, new_part)) {
            MetaStoreServerUtils.updateBasicState(environmentContext, new_part.getParameters());
          } else {
            MetaStoreServerUtils.updatePartitionStatsFast(
                new_part, tbl, wh, false, true, environmentContext, false);
          }
        }

        // PartitionView does not have SD. We do not need update its column stats
        if (oldPart.getSd() != null) {
          updateOrGetPartitionColumnStats(msdb, catName, dbname, name, new_part.getValues(),
              oldPart.getSd().getCols(), tbl, new_part, null, null);
        }
        Deadline.checkTimeout();
        msdb.alterPartition(
            catName, dbname, name, new_part.getValues(), new_part, validWriteIds);
        if (transactionalListeners != null && !transactionalListeners.isEmpty()) {
          MetaStoreListenerNotifier.notifyEvent(transactionalListeners,
                                                EventMessage.EventType.ALTER_PARTITION,
                                                new AlterPartitionEvent(oldPart, new_part, tbl, false,
                                                        true, new_part.getWriteId(), handler),
                                                environmentContext);


        }
        success = msdb.commitTransaction();
      } catch (InvalidObjectException e) {
        LOG.warn("Alter failed", e);
        throw new InvalidOperationException("alter is not possible: " + e.getMessage());
      } catch (NoSuchObjectException e) {
        //old partition does not exist
        throw new InvalidOperationException("alter is not possible: " + e.getMessage());
      } finally {
        if(!success) {
          msdb.rollbackTransaction();
        }
      }
      return oldPart;
    }

    //rename partition
    String oldPartLoc;
    String newPartLoc;
    Path srcPath = null;
    Path destPath = null;
    FileSystem srcFs;
    FileSystem destFs = null;
    boolean dataWasMoved = false;
    Database db;
    try {
      msdb.openTransaction();
      Table tbl = msdb.getTable(catName, dbname, name, null);
      if (tbl == null) {
        throw new InvalidObjectException(
            "Unable to alter partition because table or database does not exist.");
      }
      MTable mTable = msdb.ensureGetMTable(catName, dbname, name);
      try {
        oldPart = msdb.getPartition(catName, dbname, name, part_vals);
      } catch (NoSuchObjectException e) {
        // this means there is no existing partition
        throw new InvalidObjectException(
            "Unable to rename partition because old partition does not exist");
      }

      Partition check_part;
      try {
        check_part = msdb.getPartition(catName, dbname, name, new_part.getValues());
      } catch(NoSuchObjectException e) {
        // this means there is no existing partition
        check_part = null;
      }

      if (check_part != null) {
        throw new AlreadyExistsException("Partition already exists:" + dbname + "." + name + "." +
            new_part.getValues());
      }

      // when renaming a partition, we should update
      // 1) partition SD Location
      // 2) partition column stats if there are any because of part_name field in HMS table PART_COL_STATS
      // 3) rename the partition directory if it is not an external table
      boolean shouldMoveData = !(MetaStoreUtils.isExternalTable(tbl) &&
          !MetaStoreUtils.isPropertyTrue(tbl.getParameters(), "TRANSLATED_TO_EXTERNAL"));
      if (shouldMoveData) {
        // TODO: refactor this into a separate method after master merge, this one is too big.
        try {
          db = msdb.getDatabase(catName, dbname);

          // if tbl location is available use it
          // else derive the tbl location from database location
          destPath = wh.getPartitionPath(db, tbl, new_part.getValues());
          destPath = constructRenamedPath(destPath, new Path(new_part.getSd().getLocation()));
        } catch (NoSuchObjectException e) {
          LOG.debug("Didn't find object in metastore ", e);
          throw new InvalidOperationException(
            "Unable to change partition or table. Database " + dbname + " does not exist"
              + " Check metastore logs for detailed stack." + e.getMessage());
        }

        if (destPath != null) {
          newPartLoc = destPath.toString();
          oldPartLoc = oldPart.getSd().getLocation();
          LOG.info("srcPath:" + oldPartLoc);
          LOG.info("descPath:" + newPartLoc);
          srcPath = new Path(oldPartLoc);
          srcFs = wh.getFs(srcPath);
          destFs = wh.getFs(destPath);
          // check that src and dest are on the same file system
          if (!FileUtils.equalsFileSystem(srcFs, destFs)) {
            throw new InvalidOperationException("New table location " + destPath
              + " is on a different file system than the old location "
              + srcPath + ". This operation is not supported.");
          }

          try {
            if (srcFs.exists(srcPath)) {
              if (newPartLoc.compareTo(oldPartLoc) != 0 && destFs.exists(destPath)) {
                throw new InvalidOperationException("New location for this table "
                  + tbl.getDbName() + "." + tbl.getTableName()
                  + " already exists : " + destPath);
              }
              //if destPath's parent path doesn't exist, we should mkdir it
              Path destParentPath = destPath.getParent();
              if (!wh.mkdirs(destParentPath)) {
                  throw new MetaException("Unable to create path " + destParentPath);
              }

              boolean clonePart = Optional.ofNullable(environmentContext)
                  .map(EnvironmentContext::getProperties)
                  .map(prop -> prop.get(RENAME_PARTITION_MAKE_COPY))
                  .map(Boolean::parseBoolean)
                  .orElse(false);
              long writeId = new_part.getWriteId();

              if (writeId > 0 && clonePart) {
                LOG.debug("Making a copy of the partition directory: {} under a new location: {}", srcPath, destPath);

                if (!wh.copyDir(srcPath, destPath, ReplChangeManager.shouldEnableCm(db, tbl))) {
                  LOG.error("Copy failed for source: " + srcPath + " to destination: " + destPath);
                  throw new IOException("File copy failed.");
                }
                addTruncateBaseFile(srcPath, writeId, conf, DataFormat.DROPPED);
              } else {
                //rename the data directory
                wh.renameDir(srcPath, destPath, ReplChangeManager.shouldEnableCm(db, tbl));
              }
              LOG.info("Partition directory rename from " + srcPath + " to " + destPath + " done.");
              dataWasMoved = true;
            }
          } catch (IOException e) {
            LOG.error("Cannot rename partition directory from " + srcPath + " to " + destPath, e);
            throw new InvalidOperationException("Unable to access src or dest location for partition "
                + tbl.getDbName() + "." + tbl.getTableName() + " " + new_part.getValues());
          } catch (MetaException me) {
            LOG.error("Cannot rename partition directory from " + srcPath + " to " + destPath, me);
            throw me;
          }
          new_part.getSd().setLocation(newPartLoc);
        }
      } else {
        new_part.getSd().setLocation(oldPart.getSd().getLocation());
      }

      if (MetaStoreServerUtils.requireCalStats(oldPart, new_part, tbl, environmentContext)) {
        MetaStoreServerUtils.updatePartitionStatsFast(
            new_part, tbl, wh, false, true, environmentContext, false);
      }

      String newPartName = Warehouse.makePartName(tbl.getPartitionKeys(), new_part.getValues());
      List<ColumnStatistics> multiColumnStats = updateOrGetPartitionColumnStats(msdb, catName, dbname, name, oldPart.getValues(),
          oldPart.getSd().getCols(), tbl, new_part, null, null);
      msdb.alterPartition(catName, dbname, name, part_vals, new_part, validWriteIds);
      if (!multiColumnStats.isEmpty()) {
        for (ColumnStatistics cs : multiColumnStats) {
          cs.getStatsDesc().setPartName(newPartName);
          try {
            msdb.updatePartitionColumnStatistics(tbl, mTable, cs, new_part.getValues(),
                validWriteIds, new_part.getWriteId());
          } catch (InvalidInputException iie) {
            throw new InvalidOperationException("Unable to update partition stats in table rename." + iie);
          } catch (NoSuchObjectException nsoe) {
            // It is ok, ignore
          }
        }
      }

      if (transactionalListeners != null && !transactionalListeners.isEmpty()) {
        MetaStoreListenerNotifier.notifyEvent(transactionalListeners,
                                              EventMessage.EventType.ALTER_PARTITION,
                                              new AlterPartitionEvent(oldPart, new_part, tbl, false,
                                                      true, new_part.getWriteId(), handler),
                                              environmentContext);
      }

      success = msdb.commitTransaction();
    } finally {
      if (!success) {
        LOG.error("Failed to rename a partition. Rollback transaction");
        msdb.rollbackTransaction();
        if (dataWasMoved) {
          LOG.error("Revert the data move in renaming a partition.");
          try {
            if (destFs.exists(destPath)) {
              wh.renameDir(destPath, srcPath, false);
            }
          } catch (MetaException me) {
            LOG.error("Failed to restore partition data from " + destPath + " to " + srcPath
                +  " in alter partition failure. Manual restore is needed.");
          } catch (IOException ioe) {
            LOG.error("Failed to restore partition data from " + destPath + " to " + srcPath
                +  " in alter partition failure. Manual restore is needed.");
          }
        }
      }
    }
    return oldPart;
  }