public Table createTable(string name, string[] primaryKeyList, params Tuple <int, string, object>[] fields)
{
if (tableExists(name)) //表已存在
{
throw new Exception(String.Format("表{0}已经存在!", name));
}
TableHeadCell thc = new TableHeadCell(tableName: name, columnNameList: new List <string>(),
columnTypeList: new List <int>(), cellIds: new List <List <long> >(), defaultValue: new List <Element>(),
primaryIndex: new List <int>());
if (fields == null || fields.Length == 0)
{
throw new Exception("建立表至少要有一个字段");
}
for (int i = 0; i < fields.Length; i++)
{
int type = fields[i].Item1;
string fieldName = fields[i].Item2;
object defaultValue = fields[i].Item3;
if (thc.columnNameList.Contains(fieldName))
{
throw new Exception(String.Format("重复声明的字段:{0}.", fieldName));
}
thc.columnNameList.Add(fieldName);
thc.columnTypeList.Add(type);
thc.defaultValue.Add(FieldType.setValue(defaultValue, type));
}
if (primaryKeyList != null && primaryKeyList.Length > 0)
{
for (int i = 0; i < primaryKeyList.Length; i++)
{
string key = primaryKeyList[i];
if (!thc.columnNameList.Contains(key))
{
throw new Exception(String.Format("字段{0}不在字段列表中，不能作为主键.", key));
}
thc.primaryIndex.Add(thc.columnNameList.IndexOf(key));
}
}
//cell已经建好，存储于云端
Global.CloudStorage.SaveTableHeadCell(thc);
//向数据库写入表的信息，并更新到云
tableIdList.Add(thc.CellID);
tableNameList.Add(thc.tableName);
//更新databasecell
DatabaseCell dc = new DatabaseCell(this.name, tableNameList, tableIdList);
long databaseId = HashHelper.HashString2Int64(this.name);
Global.CloudStorage.SaveDatabaseCell(databaseId, dc);
return(new Table(name));
}
public void rename(string newName)
{
long tableId = Database.getCurrentDatabase().getTableIdList().ElementAt(Database.getCurrentDatabase().getTableNameList().IndexOf(tableNames
[0]));
TableHeadCell thc = new TableHeadCell(newName, this.columnNames, this.columnTypes, this.primaryIndexs, this.defaultValues, this.cellIds);
Global.CloudStorage.SaveTableHeadCell(tableId, thc);
//更改数据库里的tablelist信息
List <string> tbName = Database.getCurrentDatabase().getTableNameList();
List <long> tbID = Database.getCurrentDatabase().getTableIdList();
tbName.RemoveAt(tbID.IndexOf(tableId));
tbID.Remove(tableId);
tbName.Add(newName);
tbID.Add(tableId);
long dbId = HashHelper.HashString2Int64(Database.getCurrentDatabase().getName());
DatabaseCell dbc = new DatabaseCell(Database.getCurrentDatabase().getName(), tbName, tbID);
Global.CloudStorage.SaveDatabaseCell(dbId, dbc);
}
/// <summary>
/// 建立一个新的数据库
/// </summary>
/// <param name="name">数据库的名字</param>
/// <returns>对应于该数据库的Database的实例化对象</returns>
public static Database createDatabase(string name)
{
long databaseId = HashHelper.HashString2Int64(name);
//先确认该数据库并不存在
if (Global.CloudStorage.Contains(databaseId))
{
throw new Exception(String.Format("数据库{0}已经存在!", name));
}
DatabaseCell dbc = new DatabaseCell(name: name, tableIdList: new List <long>(),
tableNameList: new List <string>());
//以数据库名的hash为cellId，存入云端
Global.CloudStorage.SaveDatabaseCell(databaseId, dbc);
Database database = new Database(name, dbc.tableIdList, dbc.tableNameList);
currentDatabase = database;
return(database);
}
/// <summary>
/// 删除一个已经存在的表
/// </summary>
/// <param name="name">要删除的表名</param>
public void dropTable(string name)
{
if (!tableExists(name))
{
throw new Exception(String.Format("表{0}不存在.", name));
}
new Table(name).truncate(); //先清空
//先移除cell
long cellId = tableIdList.ElementAt(tableNameList.IndexOf(name));
Global.CloudStorage.RemoveCell(cellId);
//再移除数据库内信息
tableNameList.Remove(name);
tableIdList.Remove(cellId);
//再同步云端的数据库
DatabaseCell dc = new DatabaseCell(this.name, tableNameList, tableIdList);
long databaseId = HashHelper.HashString2Int64(this.name);
Global.CloudStorage.SaveDatabaseCell(databaseId, dc);
}
