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FdoISelectAggregates Class Reference

#include <ISelectAggregates.h>

Inherits FdoIBaseSelect.

Inheritance diagram for FdoISelectAggregates:

[legend]
List of all members.

Detailed Description

The FdoISelectAggregate interface defines a Select command that handle selection of properties that include the use of aggregate functions. This command differs from the FdoISelect command in a number of ways. It handles selection of properties that are aggregate functions and supports selecting distinct property values. It also includes grouping criteria. The execute method returns an IDataReader which is not tied to a specific class. Unlike Select, FdoISelectAggregate does not include any locking functions.

Definition at line 40 of file ISelectAggregates.h.


Public Member Functions

virtual FDO_API FdoIDataReaderExecute ()=0
 Executes the select command and returns a reference to an FdoIDataReader.
virtual FDO_API bool GetDistinct ()=0
 Get the distinct option.
virtual FDO_API FdoIdentifierCollectionGetGrouping ()=0
 Gets the FdoIdentifierCollection that holds the list of group by property names. If empty no grouping is used. This list is initially empty and the caller need to add the property that the command should use as a group by criteria. No LOB or Geometry type properties can be used for ordering.
virtual FDO_API FdoFilterGetGroupingFilter ()=0
 Gets the grouping by filter.
virtual FDO_API void SetDistinct (bool value)=0
 Set the distinct option of the selection. Non-simple properties such as object properties, geometry properties, raster properties, association properties, etc. will not be supported with Distinct.
virtual FDO_API void SetGroupingFilter (FdoFilter *filter)=0
 Set the grouping by filter. Use the grouping filter to restrict the groups of returned properties to those groups for which the specified filter is TRUE. For example "order by city" and "min(lanes) = 2". The FdoFilter have to evalute to a binary value(true or false).

Friends

class FdoIConnection

Member Function Documentation

virtual FDO_API FdoIDataReader* FdoISelectAggregates::Execute  )  [pure virtual]
 

Executes the select command and returns a reference to an FdoIDataReader.

Returns:
Returns the data reader.

virtual FDO_API bool FdoISelectAggregates::GetDistinct  )  [pure virtual]
 

Get the distinct option.

Returns:
Returns true if distinct is set, false otherwise.

virtual FDO_API FdoIdentifierCollection* FdoISelectAggregates::GetGrouping  )  [pure virtual]
 

Gets the FdoIdentifierCollection that holds the list of group by property names. If empty no grouping is used. This list is initially empty and the caller need to add the property that the command should use as a group by criteria. No LOB or Geometry type properties can be used for ordering.

Returns:
Returns the list of group by property names.

virtual FDO_API FdoFilter* FdoISelectAggregates::GetGroupingFilter  )  [pure virtual]
 

Gets the grouping by filter.

Returns:
Returns the grouping filter.

virtual FDO_API void FdoISelectAggregates::SetDistinct bool  value  )  [pure virtual]
 

Set the distinct option of the selection. Non-simple properties such as object properties, geometry properties, raster properties, association properties, etc. will not be supported with Distinct.

Parameters:
value true or false; when set to true, only distinct values are returned. Otherwise all values are returned
Returns:
Returns nothing
Note:
Grouping criteria is not supported with Distinct.

virtual FDO_API void FdoISelectAggregates::SetGroupingFilter FdoFilter filter  )  [pure virtual]
 

Set the grouping by filter. Use the grouping filter to restrict the groups of returned properties to those groups for which the specified filter is TRUE. For example "order by city" and "min(lanes) = 2". The FdoFilter have to evalute to a binary value(true or false).

Parameters:
filter The grouping filter.
Returns:
Returns nothing

Friends And Related Function Documentation

friend class FdoIConnection [friend]
 

Reimplemented from FdoIBaseSelect.

Definition at line 42 of file ISelectAggregates.h.


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