Open Database Connectivity (ODBC) is a generic medium to access data from a variety of database management systems (DBMS).
An application using ODBC need not worry about the underlying DBMS from which the data is extracted. Windows’ ODBC components talks to a database management system through an appropriate driver.
A DBMS needs to have a corresponding ODBC driver.
When an application asks Windows’ ODBC components to access a DBMS, it conveys Data Source Names (DSN) to ODBC.
This DSN contains details like database name, directory, driver corresponding to the database, user id, password, etc.
Thus, the process goes something like this.
The admin tool ODBC Data Sources manages the data sources that are installed in your system. Through this tool, you can add, manage or remove Data Source Names as well as ODBC drivers to/from the system.
Thus, this tool lets you manage the Open Database Connectivity for your system.
How to Launch It
Control Panel Way
- Open “Administrative Tools” applet from the traditional Control Panel.
- Launch “ODBC Data Sources” from the list of administrative tools.
- Invoke Run window or Search Charm. Select the Settings tab in case of Search Charm.
- Type in the command “odbcad32.exe”, and hit Enter.
The interface of the tool is basically a 7-tabbed small window.
Data Source Names (User DSN, System DSN and File DSN tabs)
Each data source name contains details like
- Name of the data source
- Platform (32-bit or 64-bit)
- Corresponding ODBC driver
- Location of the data source
- User Id and password
There are two types of Data Source Names.
- User DSN – These are accessible only by the currently logged in user. The User DSN tab handles these DSNs.
- System DSN – These source names are accessible to all the local users of the system. These are handled by System DSN tab.
Normally, the information of a DSN (user or system) is stored in system registry. However, a DSN can also be stored in a file with extension “.dsn”. Such a data source name is called File DSN.
These data sources are listed in File DSN tab.
This tab lists the ODBC drivers installed in your system. ODBC requires a corresponding driver in order to access a database.
You can view driver details like
- Company that created the driver
- File name of the driver
In case the applications using ODBC start hiccupping for some unknown reason, you may want to diagnose the ODBC calls that it makes to access a database.
Through this tab, you can enable tracing of all the ODBC calls made by applications.
The calls so traced are logged into a file for debugging purpose. You can set the location of the log file, as well as the DLL file that traces the calls.
Keep in mind that tracing imposes a significant delay, and hence, lag in the database operations. So you must not forget to stop the tracing as soon as you finish debugging, as your applications will become horribly slow when accessing database.
Connection Pooling Tab
Windows maintains connection pools for each ODBC driver. A pool indicates the maximum number of connections to the corresponding DBMS.
When an application makes an ODBC call to access a database, it is assigned a connection from the corresponding driver’s pool.
This tab lists the connection pools for all the installed ODBC drivers.
You can enable a counter to measure performance of the connection pools.
This tab simply lists the core ODBC components along with details like description, version and physical location of the component.