Having trouble writing to a database although SQL query is correct

Question

Hi there. I am trying to write an sql query to a database but I am failing to understand what is going wrong in terms of executing the query.
I have the following code.
static public int writeToStockTable (String suppIn, String nameIn, String typeIn, float quantIn, float priceIn, String descIn, String styleIn, String finishIn)         {               // Temporary variable to hold the SQL query               String SQLString, SQLString2;               ResultSet rs = null;                                     // Build a string containing the SQL INSERT instruction to be used later             SQLString = "INSERT INTO "+typeIn+" VALUES ('1', '" + suppIn + "', '" + nameIn + "', " + quantIn + ", " + priceIn + ", '"+descIn+"', '"+styleIn+"', '"+finishIn+"')";             SQLString2 = "SELECT Name FROM Suppliers WHERE Name = '" + suppIn + "'";                                         try                   {                         // The createStatement() method creates a Statement object.  Object will be                         // attached to my reference variable (statement) defined at the top of class.                         statement = connectionToBellFiresDB.createStatement();                                                 // The executeUpdate() statement can be used here to execute an                         // SQL INSERT instruction.                         rs = statement.executeQuery (SQLString2);                         if ((rs == null))                         {                             System.out.println ("Trying to say no supplier");                             return (-2);                         }                                                 else                         {                             System.out.println (SQLString);                             statement.executeUpdate (SQLString);                         }                                           }                 catch (SQLException exception)                   {                       return (-1);    // Return -1 if problem writing record to file                   }                             return (0);  // Return with 0 if record successfully written                       }
Please ignore the attributes not used, it is very much a work in progress. The command that prints SQLString prints
INSERT INTO Fireplace VALUES ('1', 'a', 'a', 1.0, 1.0, 'a', 'a', 'a')
which is correct, but will return the error code -1 when asked to execute the query. The database jdbc:odbc driver has been initialised in the control panel and the program has no other problems accessing the database as far as i am aware.
Any help would be appreciated, i hate database connections :)

Answer 1

Chrift wrote:
Im sorry i dont know what you mean by eating the exception, im quite a noob at programming to be honest!
How do i print it out and what is a stack trace?Do you know what an exception is? If not, then you should stay far away from JDBC/Database programming for the time being.
Read [the Exception Tutorial|http://java.sun.com/docs/books/tutorial/essential/exceptions/] first.
Then: an exception has quite a bit of useful information attached that tells you what went wrong.
In your case you catch the exception and ignore everything it could tell you by simply returning -1. Returning 0 and -1 to indicate success/failure is a very bad idea and should not be used in Java code, it's a C-style convention for C-era programming languages. In Java you use exceptions instead.
For starters you could simply add "exception.printStackTrace()" in your catch-block to get some more information out of the exception.