MemoryTable.h

MemoryTable holds all its data in memory. It means that the data is not persistent. However, it can be copied to another table to make the data persistent. Furthermore it is a table as all other tables, so all table functions can be applied to it. Some functions (e.g. lock) won't do anything. Also all table operations like sorting, selecting, and iterating can be used.

The constructor accepts a SetupNewTable object which can contain bindings of columns to any data manager. All bindings to storage managers will be replaced by a binding to the memory based storage manager MemoryStMan. Also all unbound columns will be bound to MemoryStMan. Thus it is still possible that a column is bound to a virtual column engine like CompressComplex.

Member Description

MemoryTable (SetupNewTable&, uInt nrrow, Bool initialize)

Create the table in memory using the definitions in the SetupNewTable object.

virtual ~MemoryTable()

The destructor deletes all data.

virtual void reopenRW()

Try to reopen the table (the underlying one) for read/write access. It does nothing.

virtual Bool asBigEndian() const

Is the table stored in big or little endian format? It returns the endian format of the machine.

virtual Bool isMultiUsed (Bool checkSubTable) const

Is the table in use (i.e. open) in another process? It always returns False.

virtual const TableLock& lockOptions() const

Get the locking info. It returns PermanentLocking.

virtual void mergeLock (const TableLock& lockOptions)

Merge the given lock info with the existing one. It does nothing.

virtual Bool hasLock (FileLocker::LockType) const

Has this process the read or write lock, thus can the table be read or written safely? It always returns True.

virtual Bool lock (FileLocker::LockType, uInt nattempts)

Locking the table is a no-op.

virtual void unlock()

Unlocking the table is a no-op.

virtual void flush (Bool sync)

Flushing the table is a no-op.

virtual void resync()

Resyncing the Table is a no-op.

virtual uInt getModifyCounter() const

Get the modify counter. It always returns 0.

virtual Bool isWritable() const

Test if the table is opened as writable. It always returns True.

virtual void copy (const String& newName, int tableOption) const
virtual void deepCopy (const String& newName, const Record& dataManagerInfo, int tableOption, Bool) const

Copy the table and all its subtables. It copies the contents of each row to get a real copy.

virtual void rename (const String& newName, int tableOption)

Rename the table. The tableOption is ignored.

virtual int tableType() const

Get the table type (Table::Memory).

virtual TableDesc actualTableDesc() const

Get the actual table description.

virtual Record dataManagerInfo() const

Get the data manager info.

virtual TableRecord& keywordSet()

Get readonly access to the table keyword set.

virtual TableRecord& rwKeywordSet()

Get read/write access to the table keyword set.

virtual void flushTableInfo()

Write the TableInfo object. It does not do anything.

virtual BaseColumn* getColumn (uInt columnIndex) const

Get a column object using its index.

virtual BaseColumn* getColumn (const String& columnName) const

Get a column object using its name.

virtual Bool canAddRow() const

Test if it is possible to add a row to this table (yes).

virtual void addRow (uInt nrrow = 1, Bool initialize = True)

Add one or more rows and possibly initialize them. This will fail for tables not supporting addition of rows.

virtual Bool canRemoveRow() const

Test if it is possible to remove a row from this table (yes).

virtual void removeRow (uInt rownr)

Remove the given row.

virtual void addColumn (const ColumnDesc& columnDesc)
virtual void addColumn (const ColumnDesc& columnDesc, const String& dataManager, Bool byName)
virtual void addColumn (const ColumnDesc& columnDesc, const DataManager& dataManager)
virtual void addColumn (const TableDesc& tableDesc, const DataManager& dataManager)

Add a column to the table. If the DataManager is not a virtual engine, MemoryStMan will be used.

virtual Bool canRemoveColumn (const Vector<String>& columnNames) const

Test if columns can be removed (yes).

virtual void removeColumn (const Vector<String>& columnNames)

Remove columns.

virtual Bool canRenameColumn (const String& columnName) const

Test if a column can be renamed (yes).

virtual void renameColumn (const String& newName, const String& oldName)

Rename a column.

virtual DataManager* findDataManager (const String& dataManagerName) const

Find the data manager with the given name. There is only one storage manager (MemoryStMan) with name MSM.

MemoryTable (const MemoryTable&)

Copy constructor is forbidden, because copying a table requires some more knowledge (like table name of result). Declaring it private, makes it unusable.

MemoryTable& operator= (const MemoryTable&)

Assignment is forbidden, because copying a table requires some more knowledge (like table name of result). Declaring it private, makes it unusable.

void setup (BaseTable* btp)

Setup the main parts of the object.
Create the initial name map from the table description. This map maps a name to the name in the original table. A rename might change the map.
Create the RefColumn objects.
Create the initial TableInfo as a copy of the original BaseTable.