borland Packages Class Hierarchy dx.dataset Package
java.lang.Object +----com.borland.dx.dataset.AggOperator +----com.borland.dx.dataset.CountAggOperator
Variables Properties Methods
Implements Serializable, Cloneable
The CountAggOperator
class is instantiable subclass of the AggOperator
and defines an aggregation operation of a count.
Set the aggOperator
property of the AggDescriptor
object to this class to perform a count calculation using the property settings stored in the AggDescriptor
. Attach the AggDescriptor
object to a Column
component's agg
property to access the data that the aggregation uses.
public void add(ReadRow row, long internalRow, boolean first)A row has been added or updated.
row
internalRow
first
public void delete(ReadRow row, long internalRow)A row has been deleted or updated. The
ReadRow
parameter contains the values and
internalRow
is a unique identifier for the row.
public void init(StorageDataSet dataSet, String[] groupColumnNames, StorageDataSet aggDataSet, Column resultColumn, Column aggColumn)Initializes the
CountAggOperator
by calling the constructor of its superclass.
dataSet
StorageDataSet
that contains the aggColumn
that is being aggregated on
groupColumnNames
Column
names to perform grouping by.
aggDataSet
StorageDataSet
that contains and maintains aggregated values.
resultColumn
Column
in aggDataSet
that contains the aggregated value.
aggColumn
Column
in the DataSet
that is being aggregated on.