Quadcap Embeddable Database

com.quadcap.sql.GroupByCursor Class Reference

Inheritance diagram for com.quadcap.sql.GroupByCursor:

List of all members.

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Detailed Description

Cursor to support SQL GROUP BY.

Author:

Stan Bailes

Definition at line 70 of file GroupByCursor.java.

Public Member Functions
	GroupByCursor (Session session, Cursor cursor, Vector groupBy) throws SQLException
Row	getRow () throws SQLException
	Derived class implements this function to return the current cursor row.
void	updateRow (Row row) throws SQLException
	Replace the current cursor row with the specified row.
void	deleteRow () throws SQLException
	Delete the current cursor row.
void	beforeFirst () throws SQLException
	Position the cursor before the first row.
boolean	lastRowOfGroup ()
boolean	next () throws SQLException
	Advance the cursor and return true if we advanced to a valid row.
boolean	nextRow () throws SQLException, IOException, ClassNotFoundException
boolean	isWritable (int col) throws SQLException
	Return true if the specified column is writable.
long	size ()
	I honestly have no idea.
void	close () throws SQLException
	Close the cursor and free up any resources (including closing the cursor's transaction if that is feasible) used by the cursor.
Package Functions
final void	swapRows ()
Package Attributes
Vector	groupBy = null
int	currentRowNum = 0
byte[]	prevKey = new byte[32]
int	prevKeyLen = -1
int[]	gMap = null
BCursor	bc = null
LazyRow	prevRow = null
LazyRow	currRow = null
boolean	sameGroup = false
boolean	prev = false
Key	compare = null
TempTable	tempTable = null

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Constructor & Destructor Documentation

com.quadcap.sql.GroupByCursor.GroupByCursor (  Session  session, Cursor  cursor, Vector  groupBy )  throws SQLException

Definition at line 84 of file GroupByCursor.java. References com.quadcap.sql.TempTable.addRows(), com.quadcap.sql.GroupByCursor.beforeFirst(), com.quadcap.sql.Column.getColumn(), com.quadcap.sql.Tuple.getColumn(), com.quadcap.sql.Tuple.getColumnCount(), com.quadcap.sql.TempTable.getCursor(), com.quadcap.sql.GroupByCursor.gMap, com.quadcap.sql.GroupByCursor.groupBy, and com.quadcap.sql.GroupByCursor.tempTable.

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Member Function Documentation

void com.quadcap.sql.GroupByCursor.beforeFirst (   )  throws SQLException [virtual]

Position the cursor before the first row. Reimplemented from com.quadcap.sql.FilterCursor. Definition at line 124 of file GroupByCursor.java. References com.quadcap.sql.GroupByCursor.bc, com.quadcap.sql.GroupByCursor.nextRow(), and com.quadcap.sql.GroupByCursor.prev. Referenced by com.quadcap.sql.GroupByCursor.GroupByCursor().

void com.quadcap.sql.GroupByCursor.close (   )  throws SQLException [virtual]

Close the cursor and free up any resources (including closing the cursor's transaction if that is feasible) used by the cursor. Exceptions: SQLException  may be thrown Reimplemented from com.quadcap.sql.FilterCursor. Definition at line 192 of file GroupByCursor.java. References com.quadcap.sql.GroupByCursor.bc, com.quadcap.sql.TempTable.release(), and com.quadcap.sql.GroupByCursor.tempTable.

void com.quadcap.sql.GroupByCursor.deleteRow (   )  throws SQLException [virtual]

Delete the current cursor row. Reimplemented from com.quadcap.sql.FilterCursor. Definition at line 119 of file GroupByCursor.java.

Row com.quadcap.sql.GroupByCursor.getRow (   )  throws SQLException [virtual]

Derived class implements this function to return the current cursor row. Implementation required. Reimplemented from com.quadcap.sql.FilterCursor. Definition at line 109 of file GroupByCursor.java. References com.quadcap.sql.GroupByCursor.prevRow.

boolean com.quadcap.sql.GroupByCursor.isWritable (  int  col  )  throws SQLException [virtual]

Return true if the specified column is writable. Parameters: column  the (one-based) column number Exceptions: SQLException  may be thrown Reimplemented from com.quadcap.sql.FilterCursor. Definition at line 183 of file GroupByCursor.java. References com.quadcap.sql.GroupByCursor.isWritable(). Referenced by com.quadcap.sql.GroupByCursor.isWritable().

boolean com.quadcap.sql.GroupByCursor.lastRowOfGroup (   )

Definition at line 135 of file GroupByCursor.java. References com.quadcap.sql.GroupByCursor.sameGroup. Referenced by com.quadcap.sql.AggregateCursor.next().

boolean com.quadcap.sql.GroupByCursor.next (   )  throws SQLException [virtual]

Advance the cursor and return true if we advanced to a valid row. Reimplemented from com.quadcap.sql.FilterCursor. Definition at line 140 of file GroupByCursor.java. References com.quadcap.sql.GroupByCursor.nextRow(), and com.quadcap.sql.GroupByCursor.prev.

boolean com.quadcap.sql.GroupByCursor.nextRow (   )  throws SQLException, IOException, ClassNotFoundException

Definition at line 152 of file GroupByCursor.java. References com.quadcap.sql.GroupByCursor.bc, com.quadcap.sql.Key.compare(), com.quadcap.sql.GroupByCursor.compare, com.quadcap.sql.GroupByCursor.currRow, com.quadcap.sql.TempTable.getRow(), com.quadcap.sql.GroupByCursor.prevKey, com.quadcap.sql.GroupByCursor.prevKeyLen, com.quadcap.sql.GroupByCursor.sameGroup, com.quadcap.sql.GroupByCursor.swapRows(), and com.quadcap.sql.GroupByCursor.tempTable. Referenced by com.quadcap.sql.GroupByCursor.beforeFirst(), and com.quadcap.sql.GroupByCursor.next().

long com.quadcap.sql.GroupByCursor.size (   )

I honestly have no idea. Reimplemented from com.quadcap.sql.FilterCursor. Definition at line 190 of file GroupByCursor.java.

final void com.quadcap.sql.GroupByCursor.swapRows (   )  [package]

Definition at line 176 of file GroupByCursor.java. References com.quadcap.sql.GroupByCursor.currRow, and com.quadcap.sql.GroupByCursor.prevRow. Referenced by com.quadcap.sql.GroupByCursor.nextRow().

void com.quadcap.sql.GroupByCursor.updateRow (  Row  row  )  throws SQLException [virtual]

Replace the current cursor row with the specified row. Reimplemented from com.quadcap.sql.FilterCursor. Definition at line 114 of file GroupByCursor.java. References com.quadcap.sql.GroupByCursor.updateRow(). Referenced by com.quadcap.sql.GroupByCursor.updateRow().

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Member Data Documentation

BCursor com.quadcap.sql.GroupByCursor.bc = null [package]

Definition at line 76 of file GroupByCursor.java. Referenced by com.quadcap.sql.GroupByCursor.beforeFirst(), com.quadcap.sql.GroupByCursor.close(), and com.quadcap.sql.GroupByCursor.nextRow().

Key com.quadcap.sql.GroupByCursor.compare = null [package]

Definition at line 81 of file GroupByCursor.java. Referenced by com.quadcap.sql.GroupByCursor.nextRow().

int com.quadcap.sql.GroupByCursor.currentRowNum = 0 [package]

Definition at line 72 of file GroupByCursor.java.

LazyRow com.quadcap.sql.GroupByCursor.currRow = null [package]

Definition at line 78 of file GroupByCursor.java. Referenced by com.quadcap.sql.GroupByCursor.nextRow(), and com.quadcap.sql.GroupByCursor.swapRows().

int [] com.quadcap.sql.GroupByCursor.gMap = null [package]

Definition at line 75 of file GroupByCursor.java. Referenced by com.quadcap.sql.GroupByCursor.GroupByCursor().

Vector com.quadcap.sql.GroupByCursor.groupBy = null [package]

Definition at line 71 of file GroupByCursor.java. Referenced by com.quadcap.sql.GroupByCursor.GroupByCursor().

boolean com.quadcap.sql.GroupByCursor.prev = false [package]

Definition at line 80 of file GroupByCursor.java. Referenced by com.quadcap.sql.GroupByCursor.beforeFirst(), and com.quadcap.sql.GroupByCursor.next().

byte [] com.quadcap.sql.GroupByCursor.prevKey = new byte[32] [package]

Definition at line 73 of file GroupByCursor.java. Referenced by com.quadcap.sql.GroupByCursor.nextRow().

int com.quadcap.sql.GroupByCursor.prevKeyLen = -1 [package]

Definition at line 74 of file GroupByCursor.java. Referenced by com.quadcap.sql.GroupByCursor.nextRow().

LazyRow com.quadcap.sql.GroupByCursor.prevRow = null [package]

Definition at line 77 of file GroupByCursor.java. Referenced by com.quadcap.sql.GroupByCursor.getRow(), and com.quadcap.sql.GroupByCursor.swapRows().

boolean com.quadcap.sql.GroupByCursor.sameGroup = false [package]

Definition at line 79 of file GroupByCursor.java. Referenced by com.quadcap.sql.GroupByCursor.lastRowOfGroup(), and com.quadcap.sql.GroupByCursor.nextRow().

TempTable com.quadcap.sql.GroupByCursor.tempTable = null [package]

Definition at line 82 of file GroupByCursor.java. Referenced by com.quadcap.sql.GroupByCursor.close(), com.quadcap.sql.GroupByCursor.GroupByCursor(), and com.quadcap.sql.GroupByCursor.nextRow().