Database used:
mysql> use xiao;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> show tables;
+----------------+
| Tables_in_xiao |
+----------------+
| students |
+----------------+
1 row in set (0.00 sec)
mysql> desc students;
+-------+---------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-------+---------------------+------+-----+---------+----------------+
| id | int(10) unsigned | NO | PRI | NULL | auto_increment |
| name | char(8) | NO | | NULL | |
| sex | char(4) | NO | | NULL | |
| age | tinyint(3) unsigned | NO | | NULL | |
| tel | char(13) | YES | | - | |
+-------+---------------------+------+-----+---------+----------------+
5 rows in set (0.04 sec)
mysql> select * from students;
+----+---------+-----+-----+-------------+
| id | name | sex | age | tel |
+----+---------+-----+-----+-------------+
| 1 | xiaoye | m | 31 | 15711580618 |
| 2 | heilong | m | 31 | 13313812130 |
| 3 | baba | m | 60 | 13313818223 |
| 4 | xiaoye | m | 30 | 17750311103 |
+----+---------+-----+-----+-------------+
4 rows in set (0.00 sec)
mysql>
java example:
import com.mysql.jdbc.Driver;
import java.sql.*;
public class JDBCTest {
public static void main(String[] args) {
Connection connection = new JDBCTest().getConnection(); //call getConnection method
try {
Statement statement = connection.createStatement();
ResultSet resultSet = statement.executeQuery( "select * from students;"); // difference between executeQuery executeUpdate execute
while(resultSet.next()) { //loop resultSet, call next() Move to the first piece of data, there is no hasnext() method;
int id = resultSet.getInt( 1);
String name = resultSet.getString( 2);
String sex = resultSet.getString( 3);
int age = resultSet.getInt(4);
String tel = resultSet.getString(5);
System.out.println(id + " " + name + " " + sex + " " + age + " " + tel + ";");
}
} catch (SQLException e) {
e.printStackTrace();
}finally {
try {
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
public Connection getConnection() {
try {
Class.forName("com.mysql.jdbc.Driver"); //加载驱动
return DriverManager.getConnection("jdbc:mysql://localhost:3306/xiao", "root", "×××××××"); //Pay attention to linking database ruturn
} catch (Exception e) {
e.printStackTrace();
}
return null; //return
}
}