Jdbc增删改查
- 增
Connection conn = null;
PreparedStatement ps = null;
try {
Class.forName("com.mysql.jdbc.Dirver");
conn = DriverManager.getConnection(
"jdbc:mysql://localhost:3306/数据库名", "root", "");
ps = conn.prepareStatement("insert into 表名vaues(?,?)");
ps.setInt(1,值);
ps.setString(2,"值");
int n = ps.executeUpdate();//增删改用executeUpdate() 方法
if (n > 0) {
System.out.println("添加成功");
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if(ps!=null){
ps.close();
}
if(conn!=null){
conn.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}
2.删
Connection conn = null;
PreparedStatement ps = null;
try {
Class.forName("com.mysql.jdbc.Dirver");
conn = DriverManager.getConnection(
"jdbc:mysql://localhost:3306/数据库名 ", "root", "");
ps = conn.prepareStatement("delete from 表名 where id=?");
ps.setInt(1,值);
int n = ps.executeUpdate();//增删改用executeUpdate() 方法
if (n > 0) {
System.out.println("删除成功");
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if(ps!=null){
ps.close();
}
if(conn!=null){
conn.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}
3.改
Connection conn = null;
PreparedStatement ps = null;
try {
Class.forName("com.mysql.jdbc.Dirver");
conn = DriverManager.getConnection(
"jdbc:mysql://localhost:3306/数据库名 ", "root", "");
ps=conn.prepareStatement("update表名set 列=? ,列 =? where id=?");
ps.setString(1,新值);
ps.setInt(2,新值);
ps.setInt(3,1);
int n = ps.executeUpdate();//增删改用executeUpdate() 方法
if (n > 0) {
System.out.println("修改成功");
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if(ps!=null){
ps.close();
}
if(conn!=null){
conn.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}
4.查
Connection conn = null;
PreparedStatement ps = null;
ResultSet rs=null;
try {
Class.forName("com.mysql.jdbc.Dirver");
conn = DriverManager.getConnection(
"jdbc:mysql://localhost:3306/数据库名?characterEncoding=utf-8", "root", "");
ps = conn.prepareStatement("select * from 表名");
rs=ps.executeQuery();//查询用executeQuery()方法
while(rs.next()){
System.out.println(rs.getInt("列")+"\t"+ rs.getString("列"));
}catch (Exception e) {
e.printStackTrace();
} finally {
try {
if(rs!=null){
rs.close();
}
if(ps!=null){
ps.close();
}
if(conn!=null){
conn.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}