Ejemplo n.º 1
0
 @Override
 public int update() {
   session.commit(true);
   Database db = session.getDatabase();
   session.getUser().checkRight(table, Right.ALL);
   table.checkSupportAlter();
   table.lock(session, true, true);
   Sequence sequence = oldColumn == null ? null : oldColumn.getSequence();
   if (newColumn != null) {
     checkDefaultReferencesTable((Expression) newColumn.getDefaultExpression());
   }
   if (columnsToAdd != null) {
     for (Column column : columnsToAdd) {
       checkDefaultReferencesTable((Expression) column.getDefaultExpression());
     }
   }
   switch (type) {
     case CommandInterface.ALTER_TABLE_ALTER_COLUMN_NOT_NULL:
       {
         if (!oldColumn.isNullable()) {
           // no change
           break;
         }
         checkNoNullValues();
         oldColumn.setNullable(false);
         db.updateMeta(session, table);
         break;
       }
     case CommandInterface.ALTER_TABLE_ALTER_COLUMN_NULL:
       {
         if (oldColumn.isNullable()) {
           // no change
           break;
         }
         checkNullable();
         oldColumn.setNullable(true);
         db.updateMeta(session, table);
         break;
       }
     case CommandInterface.ALTER_TABLE_ALTER_COLUMN_DEFAULT:
       {
         checkDefaultReferencesTable(defaultExpression);
         oldColumn.setSequence(null);
         oldColumn.setDefaultExpression(session, defaultExpression);
         removeSequence(sequence);
         db.updateMeta(session, table);
         break;
       }
     case CommandInterface.ALTER_TABLE_ALTER_COLUMN_CHANGE_TYPE:
       {
         // if the change is only increasing the precision, then we don't
         // need to copy the table because the length is only a constraint,
         // and does not affect the storage structure.
         if (oldColumn.isWideningConversion(newColumn)) {
           convertAutoIncrementColumn(newColumn);
           oldColumn.copy(newColumn);
           db.updateMeta(session, table);
         } else {
           oldColumn.setSequence(null);
           oldColumn.setDefaultExpression(session, null);
           oldColumn.setConvertNullToDefault(false);
           if (oldColumn.isNullable() && !newColumn.isNullable()) {
             checkNoNullValues();
           } else if (!oldColumn.isNullable() && newColumn.isNullable()) {
             checkNullable();
           }
           convertAutoIncrementColumn(newColumn);
           copyData();
         }
         break;
       }
     case CommandInterface.ALTER_TABLE_ADD_COLUMN:
       {
         // ifNotExists only supported for single column add
         if (ifNotExists
             && columnsToAdd.size() == 1
             && table.doesColumnExist(columnsToAdd.get(0).getName())) {
           break;
         }
         for (Column column : columnsToAdd) {
           if (column.isAutoIncrement()) {
             int objId = getObjectId();
             column.convertAutoIncrementToSequence(
                 session, getSchema(), objId, table.isTemporary());
           }
         }
         copyData();
         break;
       }
     case CommandInterface.ALTER_TABLE_DROP_COLUMN:
       {
         if (table.getColumns().length == 1) {
           throw DbException.get(ErrorCode.CANNOT_DROP_LAST_COLUMN, oldColumn.getSQL());
         }
         table.dropSingleColumnConstraintsAndIndexes(session, oldColumn);
         copyData();
         break;
       }
     case CommandInterface.ALTER_TABLE_ALTER_COLUMN_SELECTIVITY:
       {
         int value = newSelectivity.optimize(session).getValue(session).getInt();
         oldColumn.setSelectivity(value);
         db.updateMeta(session, table);
         break;
       }
     default:
       DbException.throwInternalError("type=" + type);
   }
   return 0;
 }
Ejemplo n.º 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;
  }