DataStructures::Table Class Reference

Holds a set of columns, a set of rows, and rows times columns cells. More...

#include <DS_Table.h>

List of all members.

Classes

struct Cell

Holds the actual data in the table. More...

struct ColumnDescriptor

struct Row

Stores the list of cells for this row, and a special flag used for internal sorting. More...

Public Types

enum SortQueryType

Increasing or decreasing sort order.

Public Member Functions

unsigned AddColumn (const char columnName[_TABLE_MAX_COLUMN_NAME_LENGTH], ColumnType columnType)

Adds a column to the table.

void RemoveColumn (unsigned columnIndex)

Removes a column by index.

unsigned ColumnIndex (char columnName[_TABLE_MAX_COLUMN_NAME_LENGTH]) const

Gets the index of a column by name.

char * ColumnName (unsigned index) const

Gives the string name of the column at a certain index.

ColumnType GetColumnType (unsigned index) const

Returns the type of a column, referenced by index.

unsigned GetColumnCount (void) const

unsigned GetRowCount (void) const

Table::Row * AddRow (unsigned rowId)

Adds a row to the table.

bool RemoveRow (unsigned rowId)

Removes a row specified by rowId.

void RemoveRows (Table *tableContainingRowIDs)

Removes all the rows with IDs that the specified table also has.

bool UpdateCell (unsigned rowId, unsigned columnIndex, int value)

Updates a particular cell in the table.

void GetCellValueByIndex (unsigned rowIndex, unsigned columnIndex, int *output)

Note this is much less efficient to call than GetRow, then working with the cells directly. Numeric, string, binary.

Row * GetRowByID (unsigned rowId) const

Gets a row. More efficient to do this and access Row::cells than to repeatedly call GetCell. You can also update cells in rows from this function.

Row * GetRowByIndex (unsigned rowIndex, unsigned *key) const

Gets a row at a specific index. rowIndex should be less than GetRowCount().

void QueryTable (unsigned *columnIndicesSubset, unsigned numColumnSubset, FilterQuery *inclusionFilters, unsigned numInclusionFilters, unsigned *rowIds, unsigned numRowIDs, Table *result)

Queries the table, optionally returning only a subset of columns and rows.

void SortTable (Table::SortQuery *sortQueries, unsigned numSortQueries, Table::Row **out)

Sorts the table by rows.

void Clear (void)

Frees all memory in the table.

void PrintColumnHeaders (char *out, int outLength, char columnDelineator) const

Prints out the names of all the columns.

void PrintRow (char *out, int outLength, char columnDelineator, bool printDelineatorForBinary, Table::Row *inputRow) const

Writes a text representation of the row to out.

const DataStructures::List
< ColumnDescriptor > & GetColumns (void) const

Direct access to make things easier.

const
DataStructures::BPlusTree
< unsigned, Row
*, _TABLE_BPLUS_TREE_ORDER > & GetRows (void) const

Direct access to make things easier.

DataStructures::Page< unsigned,
Row *, _TABLE_BPLUS_TREE_ORDER > * GetListHead (void)

Get the head of a linked list containing all the row data.

unsigned GetAvailableRowId (void) const

Get the first free row id. This could be made more efficient.

Detailed Description

Holds a set of columns, a set of rows, and rows times columns cells.

The table data structure is useful if you want to store a set of structures and perform queries on those structures.
This is a relatively simple and fast implementation of the types of tables commonly used in databases.
See TableSerializer to serialize data members of the table.
See LightweightDatabaseClient and LightweightDatabaseServer to transmit the table over the network.

Member Function Documentation

unsigned DataStructures::Table::AddColumn	(	const char	columnName[_TABLE_MAX_COLUMN_NAME_LENGTH],
		ColumnType	columnType
	)

Adds a column to the table.

Parameters:

`[in]`	columnName	The name of the column
`[in]`	columnType	What type of data this column will hold

Returns:: The index of the new column

Table::Row* DataStructures::Table::AddRow ( unsigned rowId )

Adds a row to the table.

New rows are added with empty values for all cells. However, if you specify initialCelLValues you can specify initial values It's up to you to ensure that the values in the specific cells match the type of data used by that row rowId can be considered the primary key for the row. It is much faster to lookup a row by its rowId than by searching keys. rowId must be unique Rows are stored in sorted order in the table, using rowId as the sort key

Parameters:

`[in]`	rowId	The UNIQUE primary key for the row. This can never be changed.
`[in]`	initialCellValues	Initial values to give the row (optional)

Returns:: The newly added row

unsigned DataStructures::Table::ColumnIndex ( char columnName[_TABLE_MAX_COLUMN_NAME_LENGTH] ) const

Gets the index of a column by name.

Column indices are stored in the order they are added.

Parameters:

[in] columnName The name of the column

Returns:: The index of the column, or (unsigned)-1 if no such column

char* DataStructures::Table::ColumnName ( unsigned index ) const

Gives the string name of the column at a certain index.

Parameters:

[in] index The index of the column

Returns:: The name of the column, or 0 if an invalid index

unsigned DataStructures::Table::GetColumnCount ( void ) const

Returns the number of columns

Returns:: The number of columns in the table

ColumnType DataStructures::Table::GetColumnType ( unsigned index ) const

Returns the type of a column, referenced by index.

Parameters:

[in] index The index of the column

Returns:: The type of the column

Row* DataStructures::Table::GetRowByID ( unsigned rowId ) const

Gets a row. More efficient to do this and access Row::cells than to repeatedly call GetCell. You can also update cells in rows from this function.

Parameters:

[in] rowId The ID of the row

Returns:: The desired row, or 0 if no such row.

Row* DataStructures::Table::GetRowByIndex	(	unsigned	rowIndex,
		unsigned *	key
	)			const

Gets a row at a specific index. rowIndex should be less than GetRowCount().

Parameters:

`[in]`	rowIndex	The index of the row
`[out]`	key	The ID of the row returned

Returns:: The desired row, or 0 if no such row.

unsigned DataStructures::Table::GetRowCount ( void ) const

Returns the number of rows

Returns:: The number of rows in the table

void DataStructures::Table::PrintColumnHeaders	(	char *	out,
		int	outLength,
		char	columnDelineator
	)			const

Prints out the names of all the columns.

Parameters:

`[out]`	out	A pointer to an array of bytes which will hold the output.
`[in]`	outLength	The size of the out array
`[in]`	columnDelineator	What character to print to delineate columns

void DataStructures::Table::PrintRow	(	char *	out,
		int	outLength,
		char	columnDelineator,
		bool	printDelineatorForBinary,
		Table::Row *	inputRow
	)			const

Writes a text representation of the row to out.

Parameters:

`[out]`	out	A pointer to an array of bytes which will hold the output.
`[in]`	outLength	The size of the out array
`[in]`	columnDelineator	What character to print to delineate columns
`[in]`	printDelineatorForBinary	Binary output is not printed. True to still print the delineator.
`[in]`	inputRow	The row to print

void DataStructures::Table::QueryTable	(	unsigned *	columnIndicesSubset,
		unsigned	numColumnSubset,
		FilterQuery *	inclusionFilters,
		unsigned	numInclusionFilters,
		unsigned *	rowIds,
		unsigned	numRowIDs,
		Table *	result
	)

Queries the table, optionally returning only a subset of columns and rows.

Parameters:

`[in]`	columnSubset	An array of column indices. Only columns in this array are returned. Pass 0 for all columns
`[in]`	numColumnSubset	The number of elements in columnSubset
`[in]`	inclusionFilters	An array of FilterQuery. All filters must pass for the row to be returned.
`[in]`	numInclusionFilters	The number of elements in inclusionFilters
`[in]`	rowIds	An arrow of row IDs. Only these rows with these IDs are returned. Pass 0 for all rows.
`[in]`	numRowIDs	The number of elements in rowIds
`[out]`	result	The result of the query. If no rows are returned, the table will only have columns.

void DataStructures::Table::RemoveColumn ( unsigned columnIndex )

Removes a column by index.

Parameters:

[in] columnIndex The index of the column to remove

bool DataStructures::Table::RemoveRow ( unsigned rowId )

Removes a row specified by rowId.

Parameters:

[in] rowId The ID of the row

Returns:: true if the row was deleted. False if not.

void DataStructures::Table::RemoveRows ( Table * tableContainingRowIDs )

Removes all the rows with IDs that the specified table also has.

Parameters:

[in] tableContainingRowIDs The IDs of the rows

void DataStructures::Table::SortTable	(	Table::SortQuery *	sortQueries,
		unsigned	numSortQueries,
		Table::Row **	out
	)

Sorts the table by rows.

You can sort the table in ascending or descending order on one or more columns Columns have precedence in the order they appear in the sortQueries array If a row cell on column n has the same value as a a different row on column n, then the row will be compared on column n+1

Parameters:

`[in]`	sortQueries	A list of SortQuery structures, defining the sorts to perform on the table
`[in]`	numColumnSubset	The number of elements in numSortQueries
`[out]`	out	The address of an array of Rows, which will receive the sorted output. The array must be long enough to contain all returned rows, up to GetRowCount()

bool DataStructures::Table::UpdateCell	(	unsigned	rowId,
		unsigned	columnIndex,
		int	value
	)

Updates a particular cell in the table.

Note:: If you are going to update many cells of a particular row, it is more efficient to call GetRow and perform the operations on the row directly.
Row pointers do not change, so you can also write directly to the rows for more efficiency.

Parameters:

`[in]`	rowId	The ID of the row
`[in]`	columnIndex	The column of the cell
`[in]`	value	The data to set

The documentation for this class was generated from the following file:

d:/temp/RakNet_PC/Source/DS_Table.h


Classes
struct	Cell
	Holds the actual data in the table. More...
struct	ColumnDescriptor
struct	Row
	Stores the list of cells for this row, and a special flag used for internal sorting. More...
Public Types
enum	SortQueryType
	Increasing or decreasing sort order.
Public Member Functions
unsigned	AddColumn (const char columnName[_TABLE_MAX_COLUMN_NAME_LENGTH], ColumnType columnType)
	Adds a column to the table.
void	RemoveColumn (unsigned columnIndex)
	Removes a column by index.
unsigned	ColumnIndex (char columnName[_TABLE_MAX_COLUMN_NAME_LENGTH]) const
	Gets the index of a column by name.
char *	ColumnName (unsigned index) const
	Gives the string name of the column at a certain index.
ColumnType	GetColumnType (unsigned index) const
	Returns the type of a column, referenced by index.
unsigned	GetColumnCount (void) const
unsigned	GetRowCount (void) const
Table::Row *	AddRow (unsigned rowId)
	Adds a row to the table.
bool	RemoveRow (unsigned rowId)
	Removes a row specified by rowId.
void	RemoveRows (Table *tableContainingRowIDs)
	Removes all the rows with IDs that the specified table also has.
bool	UpdateCell (unsigned rowId, unsigned columnIndex, int value)
	Updates a particular cell in the table.
void	GetCellValueByIndex (unsigned rowIndex, unsigned columnIndex, int *output)
	Note this is much less efficient to call than GetRow, then working with the cells directly. Numeric, string, binary.
Row *	GetRowByID (unsigned rowId) const
	Gets a row. More efficient to do this and access Row::cells than to repeatedly call GetCell. You can also update cells in rows from this function.
Row *	GetRowByIndex (unsigned rowIndex, unsigned *key) const
	Gets a row at a specific index. rowIndex should be less than GetRowCount().
void	QueryTable (unsigned columnIndicesSubset, unsigned numColumnSubset, FilterQuery inclusionFilters, unsigned numInclusionFilters, unsigned rowIds, unsigned numRowIDs, Table result)
	Queries the table, optionally returning only a subset of columns and rows.
void	SortTable (Table::SortQuery sortQueries, unsigned numSortQueries, Table::Row *out)
	Sorts the table by rows.
void	Clear (void)
	Frees all memory in the table.
void	PrintColumnHeaders (char *out, int outLength, char columnDelineator) const
	Prints out the names of all the columns.
void	PrintRow (char out, int outLength, char columnDelineator, bool printDelineatorForBinary, Table::Row inputRow) const
	Writes a text representation of the row to out.
const DataStructures::List < ColumnDescriptor > &	GetColumns (void) const
	Direct access to make things easier.
const DataStructures::BPlusTree < unsigned, Row *, _TABLE_BPLUS_TREE_ORDER > &	GetRows (void) const
	Direct access to make things easier.
DataStructures::Page< unsigned, Row , _TABLE_BPLUS_TREE_ORDER >	GetListHead (void)
	Get the head of a linked list containing all the row data.
unsigned	GetAvailableRowId (void) const
	Get the first free row id. This could be made more efficient.