Accessing and Changing Relational Data
OLE DB Objects Consumed by Distributed Queries
The following table shows the OLE DB objects and interfaces consumed by Transact-SQL distributed queries. An OLE DB provider must support at least a minimal set of objects and interfaces before it can be used in any Transact-SQL distributed queries. These objects and interfaces are marked with a Yes in the Required column of the table. The objects and interfaces with a No in the Required column are needed only to support advanced distributed query functionality. If the interface is not supported by the provider, related Transact-SQL functionality is not supported. For example, if the IRowsetLocate and IRowsetChange interfaces are not supported, UPDATE or DELETE statements do not function on remote tables.
| Object | Interface | Required | Description |
|---|---|---|---|
| Data Source | IDBInitialize | Yes | Initialize and set up data and security context. |
| IDBCreateSession | Yes | Create a DB Session object. | |
| IDBProperties | Yes | Get information about the capabilities of provider and set initialization properties. | |
| IDBInfo | No | Get information about the SQL syntax supported by the provider. | |
| DB Session | IDBSchemaRowset | No | Get table and/or column meta data. Rowsets needed are TABLES and COLUMNS. Other rowsets used, if available, are TABLES_INFO, CATALOGS, INDEXES, STATISTICS, TABLE_STATISTICS, VIEWS, PRIMARY_KEYS, TABLE_PRIVILEGES, and COLUMN_PRIVILEGES. |
| IopenRowset | Yes | Open a rowset on a table, index, or histogram. | |
| IGetDataSource | Yes | Return to the data source object from a DB Session object. | |
| IDBCreateCommand | No | Create a command object (query). | |
| ITransactionLocal | No | Use to start a transaction on the provider. | |
| ITransactionJoin | No | Use for distributed transaction support. If this interface is not supported, updates against a remote provider are not allowed in a user transaction. | |
| Rowset (on a table) | Irowset | Yes | Scan rows. |
| Iaccessor | Yes | Bind to columns in a rowset. | |
| IcolumnsInfo | Yes | Get information about columns in a rowset. | |
| IrowsetInfo | Yes | Get information about rowset properties. | |
| IRowsetLocate | No | Required for UPDATE or DELETE operations and index-based lookups. | |
| IRowsetChange | No | Required for INSERT, UPDATE, or DELETE operations on a table. Rowsets against base tables should support this interface for supporting INSERT, UPDATE, or DELETE statements. | |
| IconvertType | Yes | Verify if a rowset supports specific data type conversions on its columns. | |
| Rowset (on an index) | Irowset | Yes | Scan rows. |
| Iaccessor | Yes | Bind to columns in a rowset. | |
| IcolumnsInfo | Yes | Get information about columns in a rowset. | |
| IrowsetInfo | Yes | Get information about rowset properties. | |
| IrowsetIndex | Yes | Required for rowsets on an index; used for indexing functionality (set range, seek). | |
| IconvertType | Yes | Verify if the rowset supports specific data type conversions on its columns. | |
| Command (optional) | Icommand | Yes | Use for executing queries. |
| ICommandText | Yes | Use for defining the query text. | |
| ICommandProperties | Yes | Specify required properties on rowsets returned by the command. | |
| ICommandWith Parameters |
No | Use for parameterized query execution. | |
| ICommandPrepare | No | Use for preparing a command to get meta data. | |
| Error (optional) | IerrorRecords | Yes | Get a pointer to an IErrorInfo interface for an error record. |
| IerrorInfo | Yes | Get a text description of an error record. | |
| Any Object (optional) | ISupportErrorInfo | No | Determine if a given interface supports error objects. |