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如果id已经存在,则Java更新mysql行

[英]Java updating mysql row if id already exists

I have a simple form with 5 fields. 我有一个简单的表格,有5个字段。 (txtID, txtFirstName, txtLastName, txtCheque, txtSavings). (txtID,txtFirstName,txtLastName,txtCheque,txtSavings)。 All I want to do is inserting these fields into my database table "accounts". 我想要做的就是将这些字段插入我的数据库表“accounts”。 Before that step I want to check if the ID from my txtID field already exists in my database. 在该步骤之前,我想检查我的txtID字段中的ID是否已存在于我的数据库中。 If yes then I want to update the database row with the content from the fields. 如果是,那么我想用字段中的内容更新数据库行。 And if not I want to create a new row with the content. 如果不是,我想用内容创建一个新行。 So far the check if the ID exists in my DB works but if click on my btn I get the following error message: I dont relly know what I'm doing wrong. 到目前为止,检查我的数据库中是否存在ID,但如果点击我的btn,我会收到以下错误消息:我不太清楚地知道我做错了什么。

com.mysql.jdbc.exceptions.MySQLSyntaxErrorException: You have an error in your SQL syntax; com.mysql.jdbc.exceptions.MySQLSyntaxErrorException:您的SQL语法中有错误; check the manual that corresponds to your MariaDB server version for the right syntax to use near '(LastName, FirstName,Cheque,Savings) VALUES('Tester','Markus','450.00','50.00" at line 1 检查与您的MariaDB服务器版本对应的手册,以便在'(LastName,FirstName,Check,Savings)VALUES附近使用正确的语法('Tester','Markus','450.00','50.00'在第1行

private void btnUpdateActionPerformed(java.awt.event.ActionEvent evt) {                                          
        // TODO add your handling code here:
        try{
            String id = txtID.getText();
            String checkid ="SELECT * FROM accounts where ID=?";
            pst=conn.prepareStatement(checkid);
            pst.setString(1, id);
            rs = pst.executeQuery();

            boolean recordAdded = false;
            while(!rs.next()){            
                 recordAdded = true;
            }
            if(recordAdded){
              // the statement for inserting goes here.
            }else{
                String sql ="UPDATE accounts SET " + "(LastName,FirstName,Cheque,Savings) VALUES" + "(?,?,?,?)";
                pst=conn.prepareStatement(sql);
                pst.setString(1,txtLastName.getText());
                pst.setString(2,txtFirstName.getText());                
                pst.setString(3,txtCheque.getText());
                pst.setString(4,txtSavings.getText());
                pst.executeUpdate();
                getAllAccounts();
                JOptionPane.showMessageDialog(null, "Customer Updated");
            }

        }
        catch(Exception e){
            JOptionPane.showMessageDialog(null, e);
        }
        finally {
            try{
                rs.close();
                pst.close();
                getAllAccounts();
            }
            catch(Exception e) {
            }
        }
    }

do you let me to make some changes in your code? 你让我在你的代码中做一些改变吗?

private void btnUpdateActionPerformed(java.awt.event.ActionEvent evt) {                                          

    try {

        String sql = "UPDATE accounts SET LastName = ?, FirstName = ?, Cheque = ?, Savings = ? where id = ?";
        pst=conn.prepareStatement(sql);
        pst.setString(1,txtLastName.getText());
        pst.setString(2,txtFirstName.getText());                
        pst.setString(3,txtCheque.getText());
        pst.setString(4,txtSavings.getText());
        pst.setString(5,txtID.getText());
        int updatedRowCount = pst.executeUpdate();
        // no record with id = txtID
        if(updatedRowCount == 0) {

            pst.close();                

            sql = "insert into accounts (ID,LastName,FirstName,Cheque,Savings) values (?,?,?,?,?,?) ";
            pst = conn.prepareStatement(sql);
            pst.setString(1,txtID.getText());
            pst.setString(2,txtLastName.getText());
            pst.setString(3,txtFirstName.getText());
            pst.setString(4,txtCheque.getText());
            pst.setString(5,txtSavings.getText());
            pst.executeUpdate();

        }

        getAllAccounts();
        JOptionPane.showMessageDialog(null, updatedRowCount > 0 ? "Customer Updated" : "Customer Inserted");

    }
    catch(Exception e){
        getAllAccounts();
        JOptionPane.showMessageDialog(null, e);
    }
    finally {
        try{
            pst.close();
        }
        catch(Exception e) {
        }
    }
}

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