如何使用java变量将值插入mysql表？

您好我正在尝试将值插入到mysql表中。 我正在尝试这段代码。 我已将值赋给变量，我想将该变量传递给该insert语句。 它是否正确？

code int tspent = "1"; String pid = "trng"; String tid = "2.3.4"; String rid = "tup"; String des = " polish my shoes!"; INSERT INTO `time_entry`(pid,tid,rid,tspend,description) VALUE ('"+pid+"','"+tid+"','"+rid+"',"+tspent+",'"+des+"'); 

这是我尝试过的，但我无法插入值

 try { conn=DBMgr.openConnection(); String sqlQuery = "INSERT INTO `time_entry`(pid,tid,rid,tspend,description) VALUE ('"+pid+"','"+tid+"','"+rid+"',"+tspent+",'"+des+"');"; st = conn.createStatement(); rs = st.executeQuery(sqlQuery); } 

Answer 1

尝试这个，

  String driver="com.mysql.jdbc.Driver"; String url="jdbc:mysql://localhost:3306/dbname"; String uname="username"; String pass="password"; Class.forName(driver); Connection c=(Connection) DriverManager.getConnection(url,uname,pass); Statement s=c.createStatement(); s.executeUpdate("INSERT INTO `time_entry`(pid,tid,rid,tspend,description) VALUE ('"+pid+"','"+tid+"','"+rid+"',"+tspent+",'"+des+"')"); 

Answer 2

只要查询是SQL数据操作语言语句，就应该使用executeUpdate()方法。 此外，您当前的查询易受SQL注入攻击。

你应该使用PreparedStatement ：

 PreparedStatement pstmt = conn.prepareStatement("INSERT INTO `time_entry`(pid,tid,rid,tspend,description) VALUES (?, ?, ?, ?, ?)");\ 

然后在这些索引处设置变量：

 pstmt.setString(1, pid); // Similarly for the remaining 4 // And then do an executeUpdate pstmt.executeUpdate(); 

Answer 3

使用PreparedStatement并使用其setXXX（）方法设置值。

 PreparedStatement pstmt = con.prepareStatement("INSERT INTO `time_entry` (pid,tid,rid,tspend,description) VALUE (?,?,?,?,?)"); pstmt.setString(1, pid ); pstmt.setString(2, tid); pstmt.setString(3, rid); pstmt.setInt(4, tspent); pstmt.setString(5,des ); pstmt.executeUpdate(); 

Answer 4

 import java.sql.*; class Adbs1{ public static void main(String args[]){ try{ Class.forName("com.mysql.jdbc.Driver"); Connection con=DriverManager.getConnection( "jdbc:mysql://localhost:3306/rk","root","@dmin"); //here rk is database name, root is username and password Statement stmt=con.createStatement(); stmt.executeUpdate("insert into emp values('rk11','Irfan')"); // stmt.executeUpdate("delete from emp where eid ='rk4'"); //stmt.executeUpdate("update emp set ename='sallu bhai' where eid='rk5'"); ResultSet rs=stmt.executeQuery("select * from emp"); while(rs.next()) System.out.println(rs.getString(1)+" "+rs.getString(2)); con.close(); }catch(Exception e){ System.out.println(e);} } }