예제 #1
0
파일: Schema.java 프로젝트: newsky/Lealone
  /**
   * Add a table to the schema.
   *
   * @param data the create table information
   * @return the created {@link Table} object
   */
  public Table createTable(CreateTableData data) {
    synchronized (database) {
      if (!data.temporary || data.globalTemporary) {
        database.lockMeta(data.session);
      }
      data.schema = this;

      if (data.isMemoryTable()) data.storageEngineName = MemoryStorageEngine.NAME;

      // 用默认的数据库参数
      if (data.storageEngineName == null) {
        data.storageEngineName = database.getDefaultStorageEngineName();
      }
      if (data.storageEngineName != null) {
        StorageEngine engine = StorageEngineManager.getInstance().getEngine(data.storageEngineName);
        if (engine == null) {
          try {
            engine = (StorageEngine) Utils.loadUserClass(data.storageEngineName).newInstance();
            StorageEngineManager.getInstance().registerEngine(engine);
          } catch (Exception e) {
            throw DbException.convert(e);
          }
        }

        if (engine instanceof TableFactory) {
          return ((TableFactory) engine).createTable(data);
        }
        return new StandardTable(data, engine);
      }
      throw DbException.convert(new NullPointerException("table engine is null"));
    }
  }
예제 #2
0
  private Table cloneTableStructure(
      Column[] columns, Database db, String tempName, ArrayList<Column> newColumns) {
    for (Column col : columns) {
      newColumns.add(col.getClone());
    }
    if (type == CommandInterface.ALTER_TABLE_DROP_COLUMN) {
      int position = oldColumn.getColumnId();
      newColumns.remove(position);
    } else if (type == CommandInterface.ALTER_TABLE_ADD_COLUMN) {
      int position;
      if (addBefore != null) {
        position = table.getColumn(addBefore).getColumnId();
      } else if (addAfter != null) {
        position = table.getColumn(addAfter).getColumnId() + 1;
      } else {
        position = columns.length;
      }
      for (Column column : columnsToAdd) {
        newColumns.add(position++, column);
      }
    } else if (type == CommandInterface.ALTER_TABLE_ALTER_COLUMN_CHANGE_TYPE) {
      int position = oldColumn.getColumnId();
      newColumns.remove(position);
      newColumns.add(position, newColumn);
    }

    // create a table object in order to get the SQL statement
    // can't just use this table, because most column objects are 'shared'
    // with the old table
    // still need a new id because using 0 would mean: the new table tries
    // to use the rows of the table 0 (the meta table)
    int id = db.allocateObjectId();
    CreateTableData data = new CreateTableData();
    data.tableName = tempName;
    data.id = id;
    data.columns = newColumns;
    data.temporary = table.isTemporary();
    data.persistData = table.isPersistData();
    data.persistIndexes = table.isPersistIndexes();
    data.isHidden = table.isHidden();
    data.create = true;
    data.session = session;
    data.storageEngineName = table.getStorageEngineName();
    Table newTable = getSchema().createTable(data);
    newTable.setComment(table.getComment());
    StringBuilder buff = new StringBuilder();
    buff.append(newTable.getCreateSQL());

    if (table.supportsAlterColumnWithCopyData()) {
      StringBuilder columnList = new StringBuilder();
      for (Column nc : newColumns) {
        if (columnList.length() > 0) {
          columnList.append(", ");
        }
        if (type == CommandInterface.ALTER_TABLE_ADD_COLUMN && columnsToAdd.contains(nc)) {
          Expression def = (Expression) nc.getDefaultExpression();
          columnList.append(def == null ? "NULL" : def.getSQL());
        } else {
          columnList.append(nc.getSQL());
        }
      }
      buff.append(" AS SELECT ");
      if (columnList.length() == 0) {
        // special case: insert into test select * from
        buff.append('*');
      } else {
        buff.append(columnList);
      }
      buff.append(" FROM ").append(table.getSQL());
    }
    String newTableSQL = buff.toString();
    String newTableName = newTable.getName();
    Schema newTableSchema = newTable.getSchema();
    newTable.removeChildrenAndResources(session);

    execute(newTableSQL, true);
    newTable = newTableSchema.getTableOrView(session, newTableName);
    ArrayList<String> triggers = New.arrayList();
    for (DbObject child : table.getChildren()) {
      if (child instanceof Sequence) {
        continue;
      } else if (child instanceof Index) {
        Index idx = (Index) child;
        if (idx.getIndexType().getBelongsToConstraint()) {
          continue;
        }
      }
      String createSQL = child.getCreateSQL();
      if (createSQL == null) {
        continue;
      }
      if (child instanceof TableView) {
        continue;
      } else if (child.getType() == DbObject.TABLE_OR_VIEW) {
        DbException.throwInternalError();
      }
      String quotedName = Parser.quoteIdentifier(tempName + "_" + child.getName());
      String sql = null;
      if (child instanceof ConstraintReferential) {
        ConstraintReferential r = (ConstraintReferential) child;
        if (r.getTable() != table) {
          sql = r.getCreateSQLForCopy(r.getTable(), newTable, quotedName, false);
        }
      }
      if (sql == null) {
        sql = child.getCreateSQLForCopy(newTable, quotedName);
      }
      if (sql != null) {
        if (child instanceof TriggerObject) {
          triggers.add(sql);
        } else {
          execute(sql, true);
        }
      }
    }
    table.setModified();
    // remove the sequences from the columns (except dropped columns)
    // otherwise the sequence is dropped if the table is dropped
    for (Column col : newColumns) {
      Sequence seq = col.getSequence();
      if (seq != null) {
        table.removeSequence(seq);
        col.setSequence(null);
      }
    }
    for (String sql : triggers) {
      execute(sql, true);
    }
    return newTable;
  }