JDBC and OCCI 10/29/2017

JDBC Java API to allow java program to interface with database Platform independence Database independence

JDBC applications Import the JDBC class (java.sql.*) Load the JDBC drivers Connect to the database Interact with the database using JDBC Disconnect with the database

Load the JDBC drivers Class.forName("oracle.jdbc.driver.OracleDriver").newInstance();

Connect to the database Connection Conn = DriverManager.getConnection(url,username,password); url is of the form: Jdbc:oracle:drivertype:@database Example: "jdbc:oracle:thin:@erg.csci.unt.edu:1521:ERG"

The Connection Object Statement prepareStatement CallableStatement

Using Statement Object Statement Stmt = Conn.createStatement(); ResultSet RS = Stmt.executeQuery("SELECT * from user_tables");

The ResultSet Class The resultset class provides access to a table of data generated by executing a query. Methods: Next Close getString(int columnIndex)

ResultSet Metadata ResultSetMetData rsetmd = rs.getMetaData() Method: getColumnCount getColumnDisplaySize(int column) getColumnTypeName(int column)

Close RS.close(); Stmt.close(); Conn.close();

OCCI Oracle C++ call interface Steps are similar to JDBC

Establish a connection Create an environment An OCCI driver manager maps to an OCI environment handle. env = Environment::createEnvironment (Environment::DEFAULT); Establish a connection conn = env->createConnection (user, passwd, db);

create and bind a SQL statement Statement *stmt = conn->createStatement ("SELECT * FROM user_tables"); execute the statement stmt->execute ();

get the result of the statement ResultSet *rs = stmt->getResultSet ();

The ResultSet Class The resultset class provides access to a table of data generated by executing a query. Methods: Next Close getString(int columnIndex)

Terminate the connection env->terminateConnection (conn); Environment::terminateEnvironment (env);