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OLE DB Consumer Templates Reference

The OLE DB Consumer Templates contain the following classes. The reference material also includes topics on the macros for OLE DB Consumer Templates.

Session Classes

  • CDataConnection
    Manages the connection with the data source. This is a useful class for creating clients because it encapsulates necessary objects (data source and session) and some of the work you need to do when connecting to a data source.

  • CDataSource
    Corresponds to an OLE DB data source object, representing a connection through a provider to a data source. One or more database sessions, each represented by a CSession object, can take place on a single connection.

  • CEnumerator
    Corresponds to an OLE DB enumerator object, which retrieves rowset information about available data sources.

  • CEnumeratorAccessor
    Used by CEnumerator to access the data from the enumerator rowset. This rowset consists of the data sources and enumerators visible from the current enumerator.

  • CSession
    Represents a single database access session. One or more sessions can be associated with each CDataSource object.

Accessor Classes

  • CAccessor
    Used for records that are statically bound to a data source. Use this accessor class when you know the structure of the data source.

  • CAccessorBase
    Base class for all accessor classes.

  • CDynamicAccessor
    An accessor that can be created at run time, based on the column information of the rowset. Use this class to retrieve data if you do not know the structure of the data source.

  • CDynamicParameterAccessor
    An accessor that can be used when command types are unknown. Obtains the parameter information by calling the ICommandWithParameters interface, if the provider supports the interface.

  • CDynamicStringAccessor
    Allows you to access a data source when you have no knowledge of the database's underlying structure.

  • CDynamicStringAccessorA
    Similar to CDynamicStringAccessor except that this class requests data accessed from the data store as ANSI string data.

  • CDynamicStringAccessorW
    Similar to CDynamicStringAccessor except that this class requests data accessed from the data store as UNICODE string data.

  • CManualAccessor
    An accessor with methods to handle both columns and command parameters. With this class, you can use any data types as long as the provider can convert the type.

  • CNoAccessor
    Can be used as a template argument when you do not want the class to support parameters or output columns.

  • CXMLAccessor
    Similar to CDynamicStringAccessor except that this class converts all data accessed from the data store as XML-formatted (tagged) data.

Rowset Classes

  • CAccessorRowset
    Encapsulates a rowset and its associated accessors.

  • CArrayRowset
    Used to access elements of a rowset using array syntax.

  • CBulkRowset
    Used to fetch and manipulate rows in bulk by retrieving multiple row handles with a single call.

  • CNoRowset
    Can be used as a template argument if the command does not return a rowset.

  • CRestrictions
    Used to specify restrictions for schema rowsets.

  • CRowset
    Used to manipulate, set, and retrieve rowset data.

  • CStreamRowset
    Returns an ISequentialStream object rather than a rowset; you then use the Read method to retrieve data in XML format. (SQL Server 2000 does the formatting; note that this feature works with SQL Server 2000 only.)

  • IRowsetNotifyImpl
    Provides a dummy implementation for IRowsetNotify, with empty functions for the IRowsetNotify methods OnFieldChange, OnRowChange, and OnRowsetChange.

Schema Rowset Classes and Typedef Classes

The OLE DB Templates provide you with a set of classes that correspond to the OLE DB schema rowsets.

Command Classes

  • CCommand
    Used to set and execute a parameter-based OLE DB command. To merely open a simple rowset, use CTable instead.

  • CMultipleResults
    Used as a template argument for the CCommand template when you want the command to handle multiple result sets.

  • CNoAccessor
    Used as a template argument for template classes, such as CCommand and CTable, that take an accessor class argument. Use CNoAccessor if you do not want the class to support parameters or output columns.

  • CNoMultipleResults
    Used as a template argument for the CCommand template when you want the command to handle a single rowset. CNoMultipleResults is the default value for the template argument.

  • CNoRowset
    Used as a template argument for CCommand or CTable if the command or table does not return a rowset.

  • CTable
    Used to access a simple rowset with no parameters.

Property Classes

  • CDBPropIDSet
    Used to pass an array of property IDs for which the consumer wants property information. The properties belong to one property set.

  • CDBPropSet
    Used to set properties on a provider.

Bookmark Class

  • CBookmark
    Used as an index for accessing data in a rowset.

Error Class

See Also

Concepts

OLE DB Provider Templates Reference

Other Resources

OLE DB Templates