java.sql.SQLException:field id 没有默认值

Question

I'm developing an Employee Payroll Management system using Java and MySQL. When I'm trying to add a record then this error is occuring.

My code is here:

    try { 
         String sql ="insert into Staff_information " 
            + "(first_name,surname,Dob,Email," 
            + "Telephone,Address,Department," 
            + "Image,Salary,Gender,Address2," 
            + "Post_code, Designation,Status,job_title,Apartment,Date_hired)          values (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?) ";
         pst=conn.prepareStatement(sql); 
         pst.setString(1,txt_firstname.getText());
         pst.setString(2,txt_surname.getText()); 
         pst.setString(3,txt_dob.getText()); 
         pst.setString(4,txt_email.getText());
         pst.setString(5,txt_tel.getText()); 
         pst.setString(6,txt_address.getText()); 
         pst.setString(7,txt_dep.getText());
         pst.setBytes(8,person_image);
         pst.setString(9,txt_salary.getText()); 
         pst.setString(10,gender);
         pst.setString(11,txt_add2.getText());  
         pst.setString(12,txt_pc.getText());
         pst.setString(13,txt_design.getText()); 
         pst.setString(14,txt_status.getText()); 
         pst.setString(15,txt_job.getText());
         pst.setString(16,txt_apt.getText());
         pst.setString(17,txt_doj.getText());
         pst.execute();
         JOptionPane.showMessageDialog(null,"Data is saved successfully");
    } catch (Exception e) { 
        JOptionPane.showMessageDialog(null,e);
    } finally{
        try {
           rs.close();
           pst.close(); 
        } catch(Exception e) { 
           JOptionPane.showMessageDialog(null,e);
        } 
    }
}                                        

Answer 1

Your table also has a not-null column id (probably the primary key), without a default value. That means that you must assign a value in your query.

It could also mean that you meant for it to be an identity column ( AUTO_INCREMENT ), but forgot to set it as one.

Answer 2

Only reason for this error could be that you have a column id in your table Staff_information that can't be NULL and you haven't passed a value for it in your query.

Either pass a value for column id in your query or if it is primary key , set it to auto increment

Answer 3

I think you have a column with name "id" which might configured as not null or unique or primarykey .

As you are not supplying value for that column your JDBC driver is throwing error.

To resolve this you can explicitly supply the value adding the column in your SQL query or else you can configure that column to be auto increment if the column type is number.

Other than this as the query you are trying to execute is non-select query it won't return a ResulSet . So, the statement rs.close() is not require.

Also I suggest you to use The try-with-resources Statement . Using this you can avoid below statements in your code.

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

Answer 4

Probably your table Staff_information has an ID column, which is mandatory (not nullable ) and the value is not supplied in the insert query.

Please check your table definition. If the ID column is primary key, then you need to pass the value in the query or define the column to be auto increment