DataStructures::Table Class Reference

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. More...

#include <DS_Table.h>

List of all members.

Public Types
enum	ColumnType { NUMERIC, STRING, BINARY }
enum	FilterQueryType {   QF_EQUAL, QF_NOT_EQUAL, QF_GREATER_THAN, QF_LESS_THAN,   QF_IS_EMPTY, QF_NOT_EMPTY }
enum	SortQueryType { QS_INCREASING_ORDER, QS_DECREASING_ORDER }
	Increasing or decreasing sort order.
Public Member Functions
	Table ()
	Constructor.
	~Table ()
	Destructor.
unsigned	AddColumn (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])
	Gets the index of a column by name Column indices are stored in the order they are added.
char *	ColumnName (unsigned index)
	Gives the string name of the column at a certain index.
ColumnType	GetColumnType (unsigned index)
	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 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.
Table::Row *	AddRow (unsigned rowId, DataStructures::List< Cell > &initialCellValues)
void	RemoveRow (unsigned rowId)
void	RemoveRows (Table *tableContainingRowIDs)
bool	UpdateCell (unsigned rowId, unsigned columnIndex, int value)
bool	UpdateCell (unsigned rowId, unsigned columnIndex, char *str)
bool	UpdateCell (unsigned rowId, unsigned columnIndex, int byteLength, char *data)
Row *	GetRowByID (unsigned rowId)
Row *	GetRowByIndex (unsigned rowIndex)
void	QueryTable (unsigned *columnSubset, 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 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.
void	Clear (void)
	Frees all memory in the table.
void	PrintRow (char *out, int outLength, char columnDelineator, bool printDelineatorForBinary, Table::Row *inputRow)
DataStructures::List< ColumnDescriptor > &	GetColumns (void)
	Direct access to make things easier.
DataStructures::BPlusTree< unsigned, Row *, _TABLE_BPLUS_TREE_ORDER > &	GetRows (void)
	Direct access to make things easier.
DataStructures::Page< unsigned, DataStructures::Table::Row *, _TABLE_BPLUS_TREE_ORDER > *	GetListHead (void)
Protected Member Functions
Table::Row *	AddRowColumns (unsigned rowId, Row *row, DataStructures::List< unsigned > columnIndices)
void	DeleteRow (Row *row)
void	QueryRow (DataStructures::List< unsigned > &inclusionFilterColumnIndices, DataStructures::List< unsigned > &columnIndicesToReturn, unsigned key, Table::Row *row, FilterQuery *inclusionFilters, Table *result)
Protected Attributes
DataStructures::BPlusTree< unsigned, Row *, _TABLE_BPLUS_TREE_ORDER >	rows
DataStructures::List< ColumnDescriptor >	columns
Classes
struct	Cell
	Holds the actual data in the table. More...
struct	ColumnDescriptor
struct	FilterQuery
struct	Row
	Stores the list of cells for this row, and a special flag used for internal sorting. More...
struct	SortQuery

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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.

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Member Function Documentation

unsigned Table::AddColumn (  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 * 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 Table::ColumnIndex (  char  columnName[_TABLE_MAX_COLUMN_NAME_LENGTH]  )

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 * Table::ColumnName (  unsigned  index  )

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 Table::GetColumnCount (  void   )  const

Returns the number of columns Returns: The number of columns in the table

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

Returns the type of a column, referenced by index. Parameters: [in]  index  The index of the column Returns: The type of the column

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

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.

Table::Row * Table::GetRowByIndex (  unsigned  rowIndex  )

Gets a row at a specific index rowIndex should be less than GetRowCount() Parameters: [in]  rowIndex  The index of the row Returns: The desired row, or 0 if no such row.

unsigned Table::GetRowCount (  void   )  const

Returns the number of rows Returns: The number of rows in the table

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

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 Table::QueryTable (  unsigned *  columnSubset, 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 Table::RemoveColumn (  unsigned  columnIndex  )

Removes a column by index. Parameters: [in]  columnIndex  The index of the column to remove

void Table::RemoveRow (  unsigned  rowId  )

Removes a row specified by rowId Parameters: [in]  rowId  The ID of the row

void 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 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 Table::UpdateCell (  unsigned  rowId, unsigned  columnIndex, int  value )

Parameters: [in]  columnIndex  The column of the cell [in]  value  The data to set

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

• C:/RakNet 2.518/Include/DS_Table.h
• C:/RakNet 2.518/Source/DS_Table.cpp

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