| executeQuery(String sql) | executeUpdate(String sql) |
| 반환값이 있는 경우 | 반환값이 없는 경우 |
| select | insert, delete, update |
'JAVA > 20_jdbc' 카테고리의 다른 글
| 하나의 페이지에 CRUD-Connection,Statement,ResultSet,executeQuery,executeUpdate (0) | 2021.02.17 |
|---|
JAVA/20_jdbc
executeQuery / executeUpdate
2021. 2. 18. 00:00
하나의 페이지에 CRUD-Connection,Statement,ResultSet,executeQuery,executeUpdate
2021. 2. 17. 00:00
- if (repeat.equalsIgnoreCase("y") {
- System.exit(0);
- Connection conn=connection();
- Statement stmt = conn.createStatement();
- ResultSet rs = stmt.executQuery(sql);
- int gno=rs.getInt("gno");
- conn.close();
- String sql = "update gift set gname= '" + gname + "' where gno=" + num;
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package ex02_jdbc_Statement;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Scanner;
//Gift table CRUD
//.close() 닫는것만 있는 method생성
//update세분화하기(+switch case)
public class GiftCRUD {
public static void main(String[] args) throws ClassNotFoundException, SQLException {
System.out.println("<<<<<<<CRUD PROGRAM>>>>>>");
Scanner sc = new Scanner(System.in);
while (true) {
System.out.print("원하는 기능의 번호를 입력해주세요.(select:1, insert:2, updaet:3, delete:4)=>");
int num = sc.nextInt();
switch (num) {
case 1:
select();
break;
case 2:
insert();
break;
case 3:
update();
break;
case 4:
delete();
break;
default:
System.out.print("잘못 입력하셨습니다. 다시 입력해주세요.\n");
continue;
} // switch end
System.out.print("프로그램을 계속하시겠습니까?(y/n)=>");
String repeat = sc.next();
if (repeat.equalsIgnoreCase("y")) {
continue;
} else {
System.out.println("CRUD PROGRAM을 종료합니다.");
System.exit(0);
} // if end
} // while end
}
// 연결
public static Connection connection() throws ClassNotFoundException, SQLException {
// 1.Driver Load - exception발생
Class.forName("oracle.jdbc.OracleDriver"); // 방법2
// 2.Connection & Open
String url = "jdbc:oracle:thin:@127.0.0.1:1521:XE";
String uid = "db명";
String pwd = "비밀번호";
Connection conn = DriverManager.getConnection(url, uid, pwd); // ==>예외발생
return conn;
}
// SELECT
public static void select() throws ClassNotFoundException, SQLException {
Connection conn = connection();
System.out.println("<<<SELECT>>>");
// 3.사용(DML 명령어 - select)
Statement stmt = conn.createStatement();
String sql = "SELECT * FROM GIFT"; // 소문자->대문자로 ==> ctrl+shift+x
ResultSet rs = stmt.executeQuery(sql);
System.out.println("상품번호 \t상품명 \t최저가 \t최고가");
while (rs.next()) { // rs의 다음요소가 있다면
int gno = rs.getInt("gno"); // 방법1-index번호사용
String gname = rs.getNString("gname"); // 방법2-필드명사용
int g_s = rs.getInt("g_start");
int g_e = rs.getInt("g_end");
System.out.println(gno + "\t" + gname + "\t" + g_s + "\t" + g_e);
} // while end
// 4.자원반환(닫기)
rs.close();
stmt.close();
conn.close();
}
// INSERT
public static void insert() throws ClassNotFoundException, SQLException {
Scanner sc = new Scanner(System.in);
Connection conn = connection();
System.out.println("<<<INSERT>>>");
// 3.사용(DML 명령어 - insert)
Statement stmt = conn.createStatement();
System.out.print("상품번호를 입력해주세요=>");
int gno = sc.nextInt();
System.out.print("상품명을 입력해주세요=>");
String gname = sc.next();
System.out.print("최저가를 입력해주세요=>");
int g_start = sc.nextInt();
System.out.print("최고가를 입력해주세요=>");
int g_end = sc.nextInt();
String sql = "INSERT INTO GIFT VALUES(" + gno + ",'" + gname + "'," + g_start + "," + g_end + ")";
int result = stmt.executeUpdate(sql);
System.out.println(result + "개 데이터 추가 성공");
// 4.자원반환(닫기)
stmt.close();
conn.close();
}
// UPDATE
public static void update() throws ClassNotFoundException, SQLException {
Scanner sc = new Scanner(System.in);
Connection conn = connection();
System.out.println("<<<UPDATE>>>");
// 3.사용(DML 명령어 - update)
Statement stmt = conn.createStatement();
System.out.print("수정할 상품번호를 입력해주세요=>");
int num = sc.nextInt();
while (true) {
System.out.print("수정할 필드명을 골라주세요(상품명:1, 최저가:2, 최고가:3)=>");
int update_num = sc.nextInt();
switch (update_num) {
case 1:
System.out.print("변경할 상품명을 입력해주세요=>");
String gname = sc.next();
String sql1 = "update gift set gname= '" + gname + "' where gno=" + num;
stmt.executeUpdate(sql1);
break;
case 2:
System.out.print("변경할 최저가를 입력해주세요=>");
int g_start = sc.nextInt();
String sql2 = "update gift set g_start= " + g_start + " where gno=" + num;
stmt.executeUpdate(sql2);
break;
case 3:
System.out.print("변경할 최고가를 입력해주세요=>");
int g_end = sc.nextInt();
String sql3 = "update gift set g_end= " + g_end + " where gno=" + num;
stmt.executeUpdate(sql3);
break;
default:
System.out.print("잘못 입력하셨습니다. 다시 입력해주세요.\n");
continue;
} // end switch
System.out.println(num + "번 상품 수정완료되었습니다.");
System.out.print("수정을 계속하시겠습니까?(y/n)=>");
String repeat = sc.next();
if (repeat.equalsIgnoreCase("y")) {
continue;
} else {
// 4.자원반환(닫기)
stmt.close();
conn.close();
break;
} //if end
}//end while
}
// DELETE
public static void delete() throws ClassNotFoundException, SQLException {
Scanner sc = new Scanner(System.in);
Connection conn = connection();
System.out.println("<<<DELETE>>>");
System.out.print("삭제할 상품의 번호를 입력해주세요=>");
int num = sc.nextInt();
// 3.사용(DML 명령어 - delete)
Statement stmt = conn.createStatement();
String sql = "DELETE FROM GIFT WHERE GNO=" + num;
stmt.executeUpdate(sql);
System.out.println(num + "번 상품 삭제가 완료되었습니다.");
// 4.자원반환(닫기)
stmt.close();
conn.close();
}
}
|
cs |
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