JDBC初探（一）

下载好JDBC之后，首先做的应该是查看它的文档

打开connector-j.html

 import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.SQLException;

 // Notice, do not import com.mysql.jdbc.*
 // or you will have problems!

 public class LoadDriver {
     public static void main(String[] args) {
         try {
             // The newInstance() call is a work around for some
             // broken Java implementations

             Class.forName("com.mysql.jdbc.Driver").newInstance();
         } catch (Exception ex) {
             // handle the error
         }
     }
 }

这是注册MySQL Connector/J，之后

 import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.SQLException;

 Connection conn = null;
 ...
 try {
     conn =
        DriverManager.getConnection("jdbc:mysql://localhost/test?" +
                                    "user=minty&password=greatsqldb");

     // Do something with the Connection

    ...
 } catch (SQLException ex) {
     // handle any errors
     System.out.println("SQLException: " + ex.getMessage());
     System.out.println("SQLState: " + ex.getSQLState());
     System.out.println("VendorError: " + ex.getErrorCode());
 }

连接数据库，之后Using JDBC Statement Objects to Execute SQL

 import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.SQLException;
 import java.sql.Statement;
 import java.sql.ResultSet;

 // assume that conn is an already created JDBC connection (see previous examples)

 Statement stmt = null;
 ResultSet rs = null;

 try {
     stmt = conn.createStatement();
     rs = stmt.executeQuery("SELECT foo FROM bar");

     // or alternatively, if you don't know ahead of time that
     // the query will be a SELECT...

     if (stmt.execute("SELECT foo FROM bar")) {
         rs = stmt.getResultSet();
     }

     // Now do something with the ResultSet ....
 }
 catch (SQLException ex){
     // handle any errors
     System.out.println("SQLException: " + ex.getMessage());
     System.out.println("SQLState: " + ex.getSQLState());
     System.out.println("VendorError: " + ex.getErrorCode());
 }
 finally {
     // it is a good idea to release
     // resources in a finally{} block
     // in reverse-order of their creation
     // if they are no-longer needed

     if (rs != null) {
         try {
             rs.close();
         } catch (SQLException sqlEx) { } // ignore

         rs = null;
     }

     if (stmt != null) {
         try {
             stmt.close();
         } catch (SQLException sqlEx) { } // ignore

         stmt = null;
     }
 }

至此，就可以完成数据库的基本操作了