Slide 12.7: Creating a Statement object

Slide 12.6: Opening a connection to a database
Slide 12.8: Executing a query
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Creating a Statement Object

Once you connect to the database and, in the process, create your Connection object, the next step is to create a Statement object. The createStatement( ) method of your JDBC Connection object returns an object of the JDBC Statement interface. Below is an example of how to create the Statement object:

  Statement stmt = conn.createStatement( );

Note that there is nothing Oracle-specific about this statement; it follows standard JDBC syntax.

When the Connection object first gets created, it is simply a direct link to the database. You use a Connection object to generate implementations of java.sql.Statement tied to the same database transaction. java.sql.Statement contains methods to execute SQL statements directly against the database and to obtain the results.

Few comments about this command:

SQL statements without parameters are normally executed using Statementobjects. If the same SQL statement is executed many times, it is more efficient to use a PreparedStatement object.

Only one ResultSet object per Statement object can be open at any point in time. Therefore, if the reading of one ResultSet object is interleaved with the reading of another, each must have been generated by different Statement objects.

All statement execute methods implicitly close a statement's current ResultSet object if an open one exists.