I am trying to populate a java database with car brands, models, and if they are available but I have a big issue. When I enter multiple cars to the table, the new car prints to the table, but previous cars I have entered also reprint
[Issue.png][1]. So first I entered Ferrari Enzo, then I entered Tesla S but Ferrari Enzo is repeating.
I know the issue is not with adding the cars to the database because if I look in the database it only shows the two I entered [DatabasePic.png][2]. I know my problem is with how I am entering my cars into the JTable. My methods are below..
ButtonClickEvent:
private void refreshbtnMouseClicked(java.awt.event.MouseEvent evt) {
try {
String Brand = brandlbl.getText();
String Model = modellbl.getText();
Boolean Available = false;
switch (availabilitybox.getSelectedItem().toString()) {
case "True":
Available = true;
break;
case "False":
Available = false;
break;
}
InsertApp nw = new InsertApp();
nw.insert(Brand, Model, Available);
nw.refreshDatabase(jTable1);
} catch (SQLException ex) {
Logger.getLogger(Window.class.getName()).log(Level.SEVERE, null, ex);
}
}
Insert Method:
public void insert(String brand, String model, Boolean available) {
String sql = "INSERT INTO CARDATA(brand,model,available) VALUES(?,?,?)";
try (Connection conn = this.connect();
PreparedStatement pstmt = conn.prepareStatement(sql)) {
pstmt.setString(1, brand);
pstmt.setString(2, model);
pstmt.setBoolean(3, available);
pstmt.executeUpdate();
} catch (SQLException e) {
System.out.println(e.getMessage());
}
}
Refreshing my database:
public void refreshDatabase(JTable table) throws SQLException {
Connection con = connect();
String SQL = "SELECT * FROM CARDATA";
Statement stmt = con.createStatement();
ResultSet rs = stmt.executeQuery(SQL);
int col = rs.getMetaData().getColumnCount();
System.out.println(col);
while (rs.next()) {
Object[] rows = new Object[col];
for (int i = 1; i <= col; i++) {
rows[i - 1] = rs.getObject(i);
}
((DefaultTableModel) table.getModel()).insertRow(rs.getRow() - 1, rows);
}
con.close();
rs.close();
stmt.close();
}
When I enter multiple cars to the table, the new car prints to the table, but previous cars I have entered also reprint
You need to clear the data in the TableModel before you start adding data back into it.
The basic code should be something like:
DefaultTableModel model = (DefaultTableModel)table.getModel();
model.setRowCount(0);
while (rs.next())
{
...
model.addRow(...);
}
Or instead of retrieving all the data from the database every time you do an insert, just add the data to the table at the same time:
pstmt.executeUpdate();
model.addRow(...);
Related
I successfully managed to populate jtable from an MS Access database using UcanAccess library.
What I want is to populate jtable from two databases. I have two databases, one contains table with four columns, the other contain three columns.
I want to populate jtable with seven columns from the two databases.
Code used :
public void PopulateJtable(JTable table, String table_name) {
String sql = "SELECT * from " + table_name;
DefaultTableModel dtm = (DefaultTableModel) table.getModel();
dtm.setRowCount(0);
try {
conn = DriverManager.getConnection(myDB);
state = conn.createStatement();
state.execute(sql);
ResultSet rs = state.getResultSet();
int columns = table.getColumnCount();
Vector vector = new Vector();
while (rs.next()) {
Vector row = new Vector();
for (int i = 1; i <= columns; i++) {
row.addElement(rs.getObject(i));
}
dtm.addRow(row);
}
} catch (SQLException e) {
JOptionPane.showMessageDialog(null, e, "ERROR !! ", 0);
} finally {
try {
state.close();
conn.close();
} catch (SQLException ex) {
Logger.getLogger(DBEngine.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
MS Access DB Tables :
table1
table2
i want to join above tables cols in one jtable
I am running a query on ID column but I don't want it to be visible in my frame/pane. How can I achieve this? Shall I make another table, is there a function in sql/mysql which allows to hide columns? I tried to google it but havent found anything yet.
Here is the code:
public void tableChanged(TableModelEvent e) {
int row = e.getFirstRow();
int col = e.getColumn();
model = (MyTableModel) e.getSource();
String stulpPav = model.getColumnName(col);
Object data = model.getValueAt(row, col);
Object studId = model.getValueAt(row, 0);
System.out.println("tableChanded works");
try {
new ImportData(stulpPav, data, studId);
} catch (ClassNotFoundException e1) {
e1.printStackTrace();
} catch (SQLException e1) {
e1.printStackTrace();
}
}
public class ImportData {
Connection connection = TableWithBottomLine.getConnection();
public ImportData(String a, Object b, Object c)
throws ClassNotFoundException, SQLException {
Statement stmt = null;
try {
String stulpPav = a;
String duom = b.toString();
String studId = c.toString();
System.out.println(duom);
connection.setAutoCommit(false);
stmt = connection.createStatement();
stmt.addBatch("update finance.fin set " + stulpPav + " = " + duom
+ " where ID = " + studId + ";");
stmt.executeBatch();
connection.commit();
} catch (BatchUpdateException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
} finally {
if (stmt != null)
stmt.close();
connection.setAutoCommit(true);
System.out.println("Data was imported to database");
}
}
}
public class MyTableModel extends AbstractTableModel{
int rowCount;
Object data [][];
String columnNames [];
public MyTableModel() throws SQLException{
String query ="SELECT ID, tbl_Date as Date, Flat, Mobile, Food, Alcohol, Transport, Outdoor, Pauls_stuff, Income, Stuff FROM finance.fin";
ResultSet rs ;
Connection connection = TableWithBottomLine.getConnection();
Statement stmt = null;
stmt = connection.createStatement();
rs = stmt.executeQuery(query);
rs.last();
rowCount = rs.getRow();
data = new Object[rowCount][11];
rs = stmt.executeQuery(query);
for (int iEil = 0; iEil < rowCount; iEil++){
rs.next();
data[iEil][0] = rs.getInt("ID");
data[iEil][1] = rs.getDate("Date");
data[iEil][2] = rs.getFloat("Flat");
data[iEil][3] = rs.getFloat("Mobile");
data[iEil][4] = rs.getFloat("Food");
data[iEil][5] = rs.getFloat("Alcohol");
data[iEil][6] = rs.getFloat("Transport");
data[iEil][7] = rs.getFloat("Outdoor");
data[iEil][8] = rs.getFloat("Pauls_stuff");
data[iEil][9] = rs.getFloat("Income");
data[iEil][10] = rs.getFloat("Stuff");
}
String[] columnName = {"ID", "Date","Flat","Mobile"
,"Food","Alcohol","Transport", "Outdoor", "Pauls_stuff", "Income", "Stuff"};
columnNames = columnName;
}
This has solved my problem:
table.removeColumn(table.getColumnModel().getColumn(0));
I placed this in my class contructor. This lets remove the column from the view of the table but column 'ID' is still contained in the TableModel. I found that many people looking for an option to exclude specific column (like autoincrement) from SELECT statement in sql / mysql but the language itself doesn't have that feature. So I hope this solution will help others as well.
Don't put ID in the select part of the query
String query ="SELECT tbl_Date as Date, Flat, Mobile, Food, Alcohol, Transport,
Outdoor, Pauls_stuff, Income, Stuff FROM finance.fin";
I've written a method that performs the following commands: select, insert, update, delete. Originally, I only wanted the first two columns of output after running SELECT * FROM SithLords. How can I get all of the rows and columns? Also, how can I allow the user to add newlines when running the select command like this:
SELECT jedi_name
FROM SithLords
WHERE level = 'master';
As of now, it only executes with one line:
select jedi_name from SithLords where level = 'master';
Code:
public void actionPerformed(ActionEvent e) {
String query = queryStatements.getText();
try {
PreparedStatement stmt = (PreparedStatement) connection.prepareStatement(query);
if(query.matches("(select|SELECT).*")) {
ResultSet result = stmt.executeQuery();
StringBuilder strResult = new StringBuilder();
while(result.next()) {
strResult.append(result.getString(1)).append(" ").append(result.getString(2));
strResult.append("\n");
}
queryResults.setText(strResult.toString());
} else if(query.matches("(insert|INSERT).*")) {
stmt.executeUpdate(query);
} else if(query.matches("(update|UPDATE).*")) {
stmt.executeUpdate(query);
} else if(query.matches("(delete|DELETE).*")) {
stmt.executeUpdate(query);
} else {
System.out.println("Not supported yet!");
}
} catch (SQLException error) {
error.printStackTrace();
}
}
If what you want is to retrieve from the recorset all its columns you could ask it how many columns does it have (n) and access from 1 to n:
ResultSet result = stmt.executeQuery();
ResultSetMetaData md = result.getMetaData();
int nCols = md.getColumnCount();
for(int c = 1; c <= nCols; c++)
strResult.append(result.getString(c).append(" "));
Concerning your multiline commands, you could replace the command end of lines by spaces:
query.replaceAll("(\\r|\\n)", " ");
I know that for remove a row i should do this:
if (table.getSelectedRow() > -1) {
int rowToTable = table.getSelectedRow();
int rowToModel = table.convertRowIndexToModel(rowToTable);
model.removeBook(rowToModel);
} else {
JOptionPane.showMessageDialog(null, "Select A Row");
}
But, Now i try this method without rowToModel variable and still remove correctly:
if (table.getSelectedRow() > -1) {
int rowToTable = table.getSelectedRow();
model.removeBook(rowToTable);
} else {
JOptionPane.showMessageDialog(null, "Select A Row");
}
My removeBook() method:
public void removeBook(int row) {
Connection connection;
PreparedStatement preparedStatement;
String query = "Delete from BookTable where id=?";
try {
connection = DriverManager.getConnection(...);
Object id = this.getValueAt(row, 0);
preparedStatement = connection.prepareStatement(query);
preparedStatement.setObject(1, id);
if (preparedStatement.executeUpdate() == 1) {
this.removeRow(row);
}
} catch (SQLException sqle) {
sqle.printStackTrace();
}
}
Why both of this works?!
And which is correct?
it works without conversion only if the table is neither sorted nor filtered - as your code can't know whether it is, it must convert the row index always. BTW, same for column index, as the user might have moved the column
I am writing a program that will take in a student ID and verify if that ID exists in a mysql table. If it does exist, I would like to take the entire row that it exists in and copy that row to another table. Currently the program will just copy all rows in a table to the other. Any help appreciated. I have inserted a snippet of code below.
try {
String compareText = IDField.getText().trim();
if(compareText.length() > 0){
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/simlab","root","password");
System.out.println("Connected to database");
Statement stmt1 = conn.createStatement();
ResultSet rs1 = stmt1.executeQuery("select * from students where LUID='"+IDField.getText()+"' ");
boolean isPresent = rs1.next();
if (isPresent)
{
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/simlab","root","password");
System.out.println("Connected to database");
int rows = stmt1.executeUpdate("INSERT INTO skills(ID_Student,LUID_Student)SELECT ID, LUID FROM students");
if (rows == 0)
{
System.out.println("Don't add any row!");
}
else
{
System.out.println(rows + " row(s)affected.");
conn.close();
}
//System.out.println("Already exists!!");
}
You could all do that in a single SQL statement:
INSERT INTO <Dest-Table>
(SELECT * FROM <Src-Table> WHERE ID=?);
It will only copy rows that exist.
I suspect it's due to this line:
int rows = stmt1.executeUpdate("INSERT INTO skills(ID_Student,LUID_Student)SELECT ID, LUID FROM students");
As, if that line is parsed, the SELECT statement has no WHERE clause, and will therefore get every row, and therefore insert everything.
With Prepared statements
String sql = "INSERT INTO abc"
+ "(SELECT id1,id2 FROM pqr)";
ps1 = con.prepareStatement(sql);
int rs = ps1.executeUpdate();
if (rs > 0) {
update = true;
} else {
update = false;
}
} catch (Exception ex) {
ex.printStackTrace();
} finally {
try {
if (ps1 != null) {
ps1.close();
ps1 = null;
}
if (con != null) {
con.close();
con = null;
}
} catch (Exception e) {
}
}
return update;