mysql - 我如何使用 select 语句

Question

我想从表中使用 select max。我想使用 PreparedStatement。我有一个复合主键，其中包含电视连续剧和 epo 编号。当我添加新的 epo 时，它将用于表并从指南表中获取电视系列代码、所有节目的内容以及每个节目的代码，然后添加到新表中。我希望它通过获取最大值来获取最后一个 epo，然后递增 +1“自动化应用程序”。

那么我如何选择 max where id =？？

如果你明白我的意思

   pstm2=con.prepareStatement(max);
   String max="select MAX(epono) as eponoo from archieve wwhere id like ? ";

Answer 1

这个程序会有帮助

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class SelectRecordsUsingPreparedStatement {
  public static Connection getConnection() throws Exception {
    String driver = "oracle.jdbc.driver.OracleDriver";
    String url = "jdbc:oracle:thin:@localhost:1521:databaseName";
    String username = "name";
    String password = "password";
    Class.forName(driver);
    Connection conn = DriverManager.getConnection(url, username, password);
    return conn;
  }

  public static void main(String[] args) {
    ResultSet rs = null;
    Connection conn = null;
    PreparedStatement pstmt = null;
    try {
      conn = getConnection();
      String query = "select deptno, deptname, deptloc from dept where deptno > ?";

      pstmt = conn.prepareStatement(query); // create a statement
      pstmt.setInt(1, 1001); // set input parameter
      rs = pstmt.executeQuery();
      // extract data from the ResultSet
      while (rs.next()) {
        int dbDeptNumber = rs.getInt(1);
        String dbDeptName = rs.getString(2);
        String dbDeptLocation = rs.getString(3);
        System.out.println(dbDeptNumber + "\t" + dbDeptName + "\t" + dbDeptLocation);
      }
    } catch (Exception e) {
      e.printStackTrace();
    } finally {
      try {
        rs.close();
        pstmt.close();
        conn.close();
      } catch (SQLException e) {
        e.printStackTrace();
      }
    }
  }
}