如何使用JDBC从ResultSet对象中删除行?
ResultSet接口的deleteRow()
方法从当前ResultSet对象中删除当前行。
//从ResultSet对象中删除列 rs.deleteRow();
假设我们有一个名为Cricketers_Data的表,其中包含6条记录,如下所示:
+----+------------+------------+---------------+----------------+-------------+ | ID | First_Name | Last_Name | Year_Of_Birth | Place_Of_Birth | Country | +----+------------+------------+---------------+----------------+-------------+ | 1 | Shikhar | Dhawan | 1981-12-05 | Delhi | India | | 2 | Jonathan | Trott | 1981-04-22 | CapeTown | SouthAfrica | | 3 | Lumara | Sangakkara | 1977-10-27 | Matale | Srilanka | | 4 | Virat | Kohli | 1988-11-05 | Delhi | India | | 5 | Rohit | Sharma | 1987-04-30 | Nagpur | India | | 6 | Ravindra | Jadeja | 1988-12-06 | Nagpur | India | +----+------------+------------+---------------+----------------+-------------+
接下来的JDBC程序建立与数据库的连接,将Cricketers_Data表的内容检索到ResultSet对象中,并从中删除一行并打印结果:
import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.Statement; public class ResultSet_DeletingRow { public static void main(String args[])throws Exception { //注册驱动程序 DriverManager.registerDriver(new com.mysql.jdbc.Driver()); //获得连接 String mysqlUrl = "jdbc:mysql://localhost/mydatabase"; Connection con = DriverManager.getConnection(mysqlUrl, "root", "password"); System.out.println("Connection established......"); //创建一个Statement对象 Statement stmt = con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE); //查询以获取employee_data表的内容 String query = "select * from Cricketers_Dataa"; //执行查询 ResultSet rs = stmt.executeQuery(query); rs.beforeFirst(); rs.absolute(3); //从ResultSet对象中删除列 rs.deleteRow(); //当前行的内容 rs.beforeFirst(); while (rs.next()) { System.out.print("id: "+rs.getInt(1)+", "); System.out.print("First name: "+rs.getString(2)+", "); System.out.print("Last name: "+rs.getString(3)+", "); System.out.print("Year of birth: "+rs.getDate(4)+", "); System.out.print("Place of birth: "+rs.getString(5)+", "); System.out.print("Country: "+rs.getString(6)+", "); System.out.println(" "); } } }
输出结果
Connection established...... id: 1, First name: Shikhar, Last name: Dhawan, Year of birth: 1981-12-05, Place of birth: Delhi, Country: India id: 2, First name: Jonathan, Last name: Trott, Year of birth: 1981-04-22, Place of birth: CapeTown, Country: SouthAfrica id: 4, First name: Virat, Last name: Kohli, Year of birth: 1988-11-05, Place of birth: Delhi, Country: India id: 5, First name: Rohit, Last name: Sharma, Year of birth: 1987-04-30, Place of birth: Nagpur, Country: India id: 6, First name: Ravindra, Last name: Jadeja, Year of birth: 1988-12-06, Place of birth: Nagpur, Country: India