Command Object Interfaces

The following table shows the mandatory and optional interfaces defined by OLE DB for a command object.

Interface	Required?	Implemented by OLE DB templates?
IAccessor	Mandatory	Yes
IColumnsInfo	Mandatory	Yes
ICommand	Mandatory	Yes
ICommandProperties	Mandatory	Yes
ICommandText	Mandatory	Yes
IConvertType	Mandatory	Yes
IColumnsRowset	Optional	No
ICommandPersist	Optional	No
ICommandPrepare	Optional	No
ICommandWithParameters	Optional	No
ISupportErrorInfo	Optional	No
ICommandStream	Optional	No

The command object uses the IAccessor to specify parameter bindings. The consumer calls IAccessor::CreateAccessor, passing it an array of DBBINDING structures. DBBINDING contains information about the column bindings (such as type and length). The provider receives the structures and determines how the data should be transferred and whether conversions are necessary.

The ICommandText interface provides a way to specify a text command. The ICommandProperties interface handles all the command properties.

See Also

Concepts

The OLE DB Provider Template Architecture