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Typically,
the standard ODBC architecture consists of four major
components:
| Application |
Responsible
for interacting with the user and for calling
ODBC functions to submit SQL statements to, and
retrieve results from, one or more data sources. |
| Driver |
Processes
the ODBC function calls, submits SQL requests to
a specific data source, and returns results to
applications. Also, the driver is responsible for
interacting with the software needed to access a
specific data source. |
| Driver Manager |
Loads/calls
drivers on behalf of an application. The driver
manager processes ODBC function calls or passes
them to the driver. |
| Data Source |
Represents
the data to be accessed. It can be a flat-file,
or a particular database in a DBMS. It also
refers to the actual location of the data as well
as any technical information needed to access the
data (driver name, network address, user ID,
password, etc.) |
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This architecture enables an application to access
different ODBC data sources, in different locations,
using the same function calls available in the ODBC API. Components interact in the
following chain of events:
- ODBC-compliant
application uses API calls to submit SQL
directives to the data source.
- Communication between
the application and ODBC driver is handled by the
driver manager, which loads the driver and passes
along the API requests.
- The ODBC driver
implements ODBC API functions for the selected
DBMS data source.
- Requests are
processed by the data source, and the results are
sent back up the chain to be retrieved by the
application.
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