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Java usesJDBC, an API that defines how a client may access a database. Its drivers may be installed first.[1][2]
The following is used to open anODBC connection to an Access database. Note that the username (and password, if applicable) are given in the DSN rather than thegetConnection call. This is a MS Windows-only example, due to the requirement for the Microsoft Access Driver.
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");Stringpath="C:/example.mdb";Stringdsn="jdbc:odbc:Driver={Microsoft Access Driver (*.mdb)};DBQ="+path+";UID=admin";accessConn=DriverManager.getConnection(dsn,"","");
try{Class.forName("com.mysql.jdbc.Driver");Connectionconn=DriverManager.getConnection("jdbc:mysql://localhost/MySite?user=MyAccount&password=MyPassword");conn.close();}catch(SQLExceptione){e.printStackTrace();}
This script returns the database size:
importjava.sql.*;importjava.io.*;importoracle.jdbc.*;importoracle.sql.*;publicclassOracleDatabase{publicstaticvoidmain(String[]args){try{DriverManager.registerDriver(neworacle.jdbc.OracleDriver());Connectionconn=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:MyDatabase","MyAccount","MyPassword");conn.setAutoCommit(true);Stringsql="SELECT sum(bytes) from dba_segments;";Statementstmt=conn.createStatement();stmt.execute(sql);stmt.close();conn.close();}catch(SQLExceptione){e.printStackTrace();}}}
try{Class.forName("org.postgresql.Driver");Connectionconn=DriverManager.getConnection("jdbc:postgresql:MyDatabase","MyAccount","MyPassword");conn.close();}catch(SQLExceptione){e.printStackTrace();}
If you have Oracle Database on your PC, just add to the classpath its following files[3]:
Otherwise, ojdbc7.jar can be downloaded fromhttp://www.oracle.com/technetwork/database/features/jdbc/jdbc-drivers-12c-download-1958347.html, and add it to the compilation. Eg:
javac MyClass.java -classpath ojdbc7.jar
Just add " as sysdba" after your Oracle account name, eg:
Connection conn = DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:MyDatabase", "MyAccount as sysdba",