Storing duplicate records in SQLite database table

I am storing data into SQLite table, and if data already exist(s) then updating it, and i am able to do that but whenever i update my existing record it saves another copy of that record...

Database:

public long InsertData(String strImageName, String strTitle) {

         try {
            SQLiteDatabase db;
            db = this.getWritableDatabase();

            ContentValues Val = new ContentValues();
            Val.put("ImageName", strImageName); 
            Val.put("Title", strTitle);             

            long rows = db.insert(TABLE_MEMBER, null, Val);

            db.close();
            return rows;

         } catch (Exception e) {
            return -1;
         }
    }


    public long UpdateData(String strImageName, String strTitle) {

         try {
            SQLiteDatabase db;
            db = this.getWritableDatabase();

            ContentValues Val = new ContentValues();
            Val.put("Title", strTitle);             

            long rows = db.update(TABLE_MEMBER, Val, "ImageName=?",
                    new String[] { String.valueOf(strImageName) });

            db.close();
            return rows;

        } catch (Exception e) {
            return -1;
        }   
    }

    public boolean Exists(String strImageName) {
           SQLiteDatabase db;
           db = this.getReadableDatabase();
           Cursor cursor = db.rawQuery("select 1 from Data where ImageName= ?", 
                new String[] { strImageName });
           boolean exists = (cursor.getCount() > 0);
           cursor.close();
           return exists;
    }

InsertDataActivity.java:-

public boolean saveData()
    {       
        long storeData = databaseDataHelper.InsertData(
                txtImageName.getText().toString(),
                editTitle.getText().toString()
                );

        if(storeData <=  0)
        {

        }
        else
        storeData = databaseDataHelper.UpdateData(
                txtImageName.getText().toString(),
                editTitle.getText().toString()  
                ); 

        return true;
    }

And one more thing, whenever i am creating database also getting .journal ... why ?