連接 mysql db:
package DBConnection;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
/***題7:如何連接數據庫,有哪些參數 (Mysql)
* 最重要的幾步是:
* 1. 注冊 jdbc 驅動:將mysql驅動注冊到DriverManager中:Class.forName("com.mysql.jdbc.Driver")
* 2. 創建連接: conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/student","root","root)
* 3. 創建 Statement: statement = conn.createStatement();
* 4. 執行查詢: Resultset rs = statement.executeQuery("select * from student");
* 5. 輪詢結果: while(rs.next()) resultset.getInt("id")/getString("name")
*/
public class ConnectMySQL{
public static void main(String[] args)
{
String sql = "SELECT * FROM student";
connectMySQL55(sql);
}
public static void connectMySQL55(String sql)
{
final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
final String DB_URL = "jdbc:mysql://localhost:3306/student";
final String USER = "root";
final String PASS = "root";
Connection conn = null; //這里是 java.sql.Connection
Statement statement = null; //這里是 java.sql.Statement
try
{
Class.forName(JDBC_DRIVER);// 注冊 JDBC 驅動
System.out.println("Connecting db ...");
conn = DriverManager.getConnection(DB_URL, USER, PASS);// 打開鏈接
statement = conn.createStatement();
ResultSet rs = statement.executeQuery(sql);
while(rs.next())
{
int id = rs.getInt("id");
String name = rs.getString("Name");
String sex = rs.getString("Sex");
System.out.println("ID: " + id);
System.out.println("Name: " + name);
System.out.println("Sex: " + sex);
}
rs.close();
statement.close();
conn.close();
} catch (SQLException se)
{
se.printStackTrace();
}
catch (Exception e)
{
e.printStackTrace();
}
finally {
try
{
if(statement != null)
{
statement.close();
}
if(conn != null)
{
conn.close();
}
} catch (Exception e2)
{
e2.printStackTrace();
}
}
}
}
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
/***題7:如何連接數據庫,有哪些參數 (Mysql)
* 最重要的幾步是:
* 1. 注冊 jdbc 驅動:將mysql驅動注冊到DriverManager中:Class.forName("com.mysql.jdbc.Driver")
* 2. 創建連接: conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/student","root","root)
* 3. 創建 Statement: statement = conn.createStatement();
* 4. 執行查詢: Resultset rs = statement.executeQuery("select * from student");
* 5. 輪詢結果: while(rs.next()) resultset.getInt("id")/getString("name")
*/
public class ConnectMySQL{
public static void main(String[] args)
{
String sql = "SELECT * FROM student";
connectMySQL55(sql);
}
public static void connectMySQL55(String sql)
{
final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
final String DB_URL = "jdbc:mysql://localhost:3306/student";
final String USER = "root";
final String PASS = "root";
Connection conn = null; //這里是 java.sql.Connection
Statement statement = null; //這里是 java.sql.Statement
try
{
Class.forName(JDBC_DRIVER);// 注冊 JDBC 驅動
System.out.println("Connecting db ...");
conn = DriverManager.getConnection(DB_URL, USER, PASS);// 打開鏈接
statement = conn.createStatement();
ResultSet rs = statement.executeQuery(sql);
while(rs.next())
{
int id = rs.getInt("id");
String name = rs.getString("Name");
String sex = rs.getString("Sex");
System.out.println("ID: " + id);
System.out.println("Name: " + name);
System.out.println("Sex: " + sex);
}
rs.close();
statement.close();
conn.close();
} catch (SQLException se)
{
se.printStackTrace();
}
catch (Exception e)
{
e.printStackTrace();
}
finally {
try
{
if(statement != null)
{
statement.close();
}
if(conn != null)
{
conn.close();
}
} catch (Exception e2)
{
e2.printStackTrace();
}
}
}
}