Java ResultSet deleteRow() 方法带示例


当我们执行某些 SQL 查询(通常是 SELECT 查询)时,它们会返回表格数据。

 java.sql.ResultSet 接口表示 SQL 语句返回的此类表格数据。

ResultSet 对象持有由执行查询数据库语句(通常是 Statement 接口的 executeQuery() 方法)的方法返回的表格数据。

ResultSet 对象有一个游标/指针,指向当前行。最初这个游标位于第一行之前。

ResultSet 接口的 deleteRow() 方法从 ResultSet 对象和表中删除当前行。

rs.deleteRow();

使用 CREATE 语句在 MySQL 数据库中创建一个名为 MyPlayers 的表,如下所示: 

CREATE TABLE MyPlayers(
   ID INT,
   First_Name VARCHAR(255),
   Last_Name VARCHAR(255),
   Date_Of_Birth date,
   Place_Of_Birth VARCHAR(255),
   Country VARCHAR(255),
   PRIMARY KEY (ID)
);

现在,我们将使用 INSERT 语句在 MyPlayers 表中插入 7 条记录

insert into MyPlayers values(1, 'Shikhar', 'Dhawan', DATE('1981-12-05'), 'Delhi', 'India');
insert into MyPlayers values(2, 'Jonathan', 'Trott', DATE('1981-04-22'), 'CapeTown', 'SouthAfrica');
insert into MyPlayers values(3, 'Kumara', 'Sangakkara', DATE('1977-10-27'), 'Matale', 'Srilanka');
insert into MyPlayers values(4, 'Virat', 'Kohli', DATE('1988-11-05'), 'Delhi', 'India');
insert into MyPlayers values(5, 'Rohit', 'Sharma', DATE('1987-04-30'), 'Nagpur', 'India');
insert into MyPlayers values(6, 'Ravindra', 'Jadeja', DATE('1988-12-06'), 'Nagpur', 'India');
insert into MyPlayers values(7, 'James', 'Anderson', DATE('1982-06-30'), 'Burnley', 'England');

下面的 JDBC 程序建立与数据库的连接,从 Myplayers 表中删除最后一条记录,并在删除操作后打印表中的内容。

示例

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class ResultSet_deleteRow {
   public static void main(String args[]) throws SQLException {
      //Registering the Driver
      DriverManager.registerDriver(new com.mysql.jdbc.Driver());
      //Getting the connection
      String mysqlUrl = "jdbc:mysql://127.0.0.1/mydatabase";
      Connection con = DriverManager.getConnection(mysqlUrl, "root", "password");
      System.out.println("Connection established......");
      //Creating the Statement
      Statement stmt = con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE);
      //Query to retrieve records
      String query = "Select * from MyPlayers";
      //Executing the query
      ResultSet rs = stmt.executeQuery(query);
      //Moving the pointer to last row
      rs.last();
      //Removing the current row from the ResultSet
      rs.deleteRow();
      rs.beforeFirst();
      System.out.println("Contents of the table after deleting a row: ");
      while(rs.next()) {
         System.out.print("ID: "+rs.getInt("ID")+", ");
         System.out.print("Name: "+rs.getString("First_Name")+", ");
         System.out.print("Age: "+rs.getString("Last_Name")+", ");
         System.out.print("Salary: "+rs.getDate("Date_Of_Birth")+", ");
         System.out.print("Country: "+rs.getString("Place_Of_Birth")+", ");
         System.out.print("Address: "+rs.getString("Country"));
         System.out.println();
      }
   }
}

输出

Connection established......
Contents of the table after deleting a row:
Connection established......
Contents of the table after deleting a row:
ID: 1, Name: Shikhar, Age: Dhawan, Salary: 1981-12-05, Country: Delhi, Address: India
ID: 2, Name: Jonathan, Age: Trott, Salary: 1981-04-22, Country: CapeTown, Address: SouthAfrica
ID: 3, Name: Kumara, Age: Sangakkara, Salary: 1977-10-27, Country: Matale, Address: Srilanka
ID: 4, Name: Virat, Age: Kohli, Salary: 1988-11-05, Country: Mumbai, Address: India
ID: 5, Name: Rohit, Age: Sharma, Salary: 1987-04-30, Country: Nagpur, Address: India
ID: 6, Name: Ravindra, Age: Jadeja, Salary: 1988-12-06, Country: Nagpur, Address: India

更新于:30-Jul-2019

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