Java Reference
In-Depth Information
7.3
Creating an ODBC Data Source
Before an ODBC-driven database can be accessed via a Java program, it is neces-
sary to register the database as an ODBC Data Source. Once this has been done, the
database can be referred to by its Data Source Name (DSN). Assuming that the
database has already been created, the steps required to set up your own ODBC
Data Source are shown below. (These instructions were used on a Windows 7
machine and the naming of some items may vary slightly with other MS operating
systems, but the basic steps should remain much the same.)
1. Select start
Run…
2. Enter cmd and click on OK.
3. Enter C:\windows\syswow64\odbcad32.exe .
4. Ensure that the User DSN tab is selected .
5. Click on the Add… button to display the Create New Data Source window.
6. Select Microsoft Access Driver (*.mdb, *.accdb) and click on Finish .
7. To locate the required database within the directory structure, click on the
Select… button.
8. Navigate through the directory structure and select your database.
9. Supply a name for the data source. ('Description' fi eld is optional.)
10. If specifying a username and password (not mandatory and not necessary for
the examples in this section), click on Advanced Options and key in the values,
clicking OK when fi nished.
11. Click OK to fi nish registration.
N.B. Remember that the above procedure is required only for ODBC databases!
The next section describes how our Java code can make use of the database's
DSN to retrieve data from the database and is applicable to any type of relational
database.
7.4
Simple Database Access
In what follows, reference will be made to Connection , Statement and ResultSet
objects. These three names actually refer to interfaces , rather than classes. Each
JDBC driver must implement these three interfaces and the implementation classes
may then be used to create objects that may conveniently be referred to as
Connection , Statement and ResultSet objects respectively. Similar comments apply
to interfaces ResultSetMetaData and DatabaseMetaData in Sect. 7.7 . From now on,
such terminology will be used freely and this point will not be laboured any further.
Using JDBC 4 to access a database requires several steps, as described below.
1. Establish a connection to the database.
2. Use the connection to create a Statement object and store a reference to this object.
3. Use the above Statement reference to run a specifi c query or update statement
and accept the result(s).
Search WWH ::




Custom Search