I'm using JDBC in sync with MySQL to add and define rows to a MySQL database's Table. The problem is that I don't know why it is throwing an Exception
when I use methods from the ResultSet
class to add rows to the table. Bear in mind that I've earlier tried just reading the table via ResultSet
methods, and, it successfully printed out the cell values. The following is the concerned code fragement:
public void run(){
try {
Class.forName("com.mysql.jdbc.Driver");
Connection con = DriverManager.getConnection(
"jdbc:mysql://localhost:3306/temp_book_database","root","1234");
ResultSet set = con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE).executeQuery("SELECT * FROM book_info");
set.moveToInsertRow();
set.updateString(1, "Osama's POV"); set.updateString(2, "Osama B Laden");
set.updateInt(3, 2800); set.updateString(4, "Osama bin Laden's debute book on terrorism");
set.insertRow(); set.moveToCurrentRow();set.beforeFirst();
//I'm guessing the bottom while loop is not executed because the above is generating the Exception
while (set.next()){
System.out.println(set.getString("Book_Title")+ set.getString("Book_Author")+ set.getString("MRP")+set.getString("Comments"));
}
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (Exception e){System.out.println("prob with code");
e.printStackTrace();}
And this is the Console:
prob with code
com.mysql.jdbc.NotUpdatable: Result Set not updatable (referenced table has no primary keys).This result set must come from a statement that was created with a result set type of ResultSet.CONCUR_UPDATABLE, the query must select only one table, can not use functions and must select all primary keys from that table. See the JDBC 2.1 API Specification, section 5.6 for more details.
at com.mysql.jdbc.UpdatableResultSet.moveToInsertRow(UpdatableResultSet.java:1013)
at testJDBCDriver.run(testJDBCDriver.java:21)
at testJDBCDriver.main(testJDBCDriver.java:9)
[UPDATE]
After adding the id
column in the table as INTEGER AUTO_INCREMENT PRIMARY KEY
the ResultSet
successfully added the row to the table, now, I just want to know why MySQL doesn't accept request to add new row from ResultSet
if the id
column isn't present in the table?