/** * 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")); } }
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; }