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How to connect two or more tables from a database to NetBeans project?

So i have the homework to make a WEB application that includes two different tables from MySQL workbench. My question is, how do i do that?
Also, i need to make both of tables interactable.
With the connector and all that?
I've tried to google basicly everything and there is no explenation so i'm kinda stuck at this point.

Actually to work with a database schema, you need to make a connection with it. After that, you can query any database entities such as tables, views, stored procedures, ... which are associated to that schema.
Without using any connection pool (which is very common in Java projects) you can use some code like this:
Class.forName("com.mysql.jdbc.Driver");
String url = "jdbc:mysql://localhost:3306/javabase";
String username = "java";
String password = "password";
System.out.println("Connecting database...");
try (Connection connection = DriverManager.getConnection(url, username, password)) {
System.out.println("Database connected!");
//execute any query
} catch (SQLException e) {
throw new IllegalStateException("Cannot connect the database!", e);
}
However, I suggest using a connection pool which is more practical. You can also refer to this thread which provides you some detail information.
Connect Java to a MySQL database

If I understood your problem right... This tutorial could help you

Java: Connecting to a MySQL Database? DriverManager.getConnection()? [duplicate]

This question already has answers here:
Connect Java to a MySQL database
(14 answers)
Closed 4 years ago.
So I was just wondering, what (and probably, how much...) have I done wrong here with this code?
try {
Class.forName("com.mysql.jdbc.Driver");
Connection c = DriverManager.getConnection("jdbc:mysql://mysql1.000webhost.com/mydatabase", "myusername", "mypassword");
} catch (SQLException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
As I've triple-checked the username/password, I'm guessing it's something wrong with the host name. The database is only on the server (I don't have any kind of saved local version or anything...do I need to?).
And also, can someone just tell me if I'm on the right lines for what I want to do? Basically I've created a piece of software with a free version and a very cheap paid version. I was thinking that to prevent piracy, since the program requires internet connection anyway, I could store their email address as the username, then their computer's MAC address would be the password (each time the program was run, I would compare the MAC address on their PC with the one registered along with their email in the database. I've got no idea whether that is a good anti-piracy measure, but I was just wondering, if I manage to get the connection working, is that something that I'd be able to do or would there be e.g. security issues with that?
Anyway, thanks in advance :)

if it is not localhost i cannot comment on the host but you also have to give port number.It is missing.
Connection con = DriverManager
.getConnection("jdbc:mysql://"+pHost+":"+pPort+"/Your_mysql_schema_name",username, password);
and also in MYSQL your schema name would be your database name.Ensure that you are giving schema name and also port number.Usually for MYSQL its 3306

Writing a piece of java code to operate your database from a remote connection is not a good idea. Someone could reverse engineer your code and change your data.
You should atleast Implement an simple service on the net that could handle the spam you might receive, and protect your data.

I Think you missed the database port no in your URL .Try this :
try {
Class.forName("com.mysql.jdbc.Driver"); // Not Required for JDBC 4.0 onwards
Connection c = DriverManager.getConnection("jdbc:mysql://mysql1.000webhost.com: 3306/mydatabase", "myusername", "mypassword");
} catch (SQLException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
}

Try instead of mysql1.000webhost.com to change with server IP address.
Example,
try {
Class.forName("com.mysql.jdbc.Driver");
Connection c = DriverManager.getConnection("jdbc:mysql://123.456.789.012:3306/mydatabase", "myusername", "mypassword");
} catch (SQLException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
}

I would recommend you some reading first. This slide show might present you how Java EE applications are build.
Next you might want to read a bit more how to connect your application with a database.
Hibernate is one of the most widely used tools for establishing connection between database and your Java program. It allows you to separate your connection data (e.g. username, password, connection url) from your code with use of configuration files in xml format. The line:
Connection c = DriverManager.getConnection("jdbc:mysql://mysql1.000webhost.com/mydatabase", "myusername", "mypassword");
Is a very dangerous way of establishing connetion, as you are providing confidential credentials inside the code. There are ways to retreive this information from binary files.
You also asked, if is it worth having some local version of your database. The anwser is: Yes. Having your database locally might significantly speed up the time required for development and testing. It also allows you to work on your code even when no internet connection is available.
Providing authentication with use of MAC address is a very dangerous idea. Those addresses are attached to given machines. In other words the user will be able to connect to your application only with machine, on which he or she created an account. When using other computer (e.g. laptop at work) authentication will be denied.

connecting to remote database with jdbc, verify credentials

I am getting a java.sql.SQLException: No suitable driver found. I am trying to connect to a remote database. I think I have all my credentials correct.
Here is my code
public static void main(String[] args) {
String dbUrl = "jdbc:mysql:sshhost/db1";
try {
Connection myConn = DriverManager.getConnection(dbUrl, "usr", "");
Statement myStat = myConn.createStatement();
ResultSet myRs = myStat.executeQuery("select * from students");
while (myRs.next()) {
System.out.println(myRs.getString("last_name") + ", " + myRs.getString("first_name"));
}
} catch (Exception e) {
e.printStackTrace();
}
}
The host is the same remote host that I ssh into.
I log on to mysql as root and this requires no password so I left the last parameter ""
The database I want to use while logged into root is called db1.
I'm not sure if my parameters are valid.

You have not loaded a driver. JDBC need to have a driver loaded before a connection can be made. So make sure you load an apt driver class using:
Class.forName("driverClass");
If you are using Java 6 or above(which included JDBC 4), you don't need the above mentioned dynamic driver class loading.
In both the cases, make sure the driver class you are using is present in your classpath.

You'll need to update your classpath to point to the mysql jar file. The JVM can't find a suitable mysql driver.

How to connect MySQL to Java program

I ve installed MySQL (last update).
I need to code, that ll create & establish a connection with SQL DB
& manage the DB(using SELECT, INSERT, CREATE).
I did everything but, I am not able to create connection. I've also installed the MySQL/J connector, I just extracted the .zip pack in a folder & added the folder path in Variables).
Can anyone tell me wat is meant by URL in the below line?
Connection connection = DriverManager.getConnection(url, username, password);
I ve tried this:
String url = "jdbc:odbc:sqlserver://localhost:3306/myfirstdb";
Connection con = DriverManager.getConnection(url, "root", "1234");
But it's not working. I am unable able to understand the term 'URL'.
Can anyone explain, the meaning of 'url' and wat should be done to connect to a SQL server from Java.
Update:
This is the Full code. It still cannot connect.
import java.sql.*;
public class TestDriver {
public static void main(String[] args) {
try {
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");//This s wat actually i did for connection
System.out.println("Driver Loaded Succesfully");
}
catch (Exception e){
System.out.println("Unable to Load Driver!!!");
}
try {
Class.forName(com.mysql.jdbc.Driver"); // initialise the driver
String url ="jdbc:mysql://localhost:3306/myfirstdb";
Connection con = DriverManager.getConnection(url, "root", "1234");
System.out.println("connection Established");
}
catch(Exception e) {
System.out.println("Couldnt get connection");
}
}
}
Can you tell me wat is the purpose of MySQL Connector/J?

In the question you seem to be using a MySQL jdbc driver with a SQL Server jdbc URL. This won't work.
If you are using a MySQL database:
Class.forName("com.mysql.jdbc.Driver"); // initialise the driver
String url ="jdbc:mysql://localhost:3306/myfirstdb";
If you are using a SQL Server database you are going to need a completely different jdbc driver. jTDS is open source and a good option. Include the jtds.jar file in your classpath and use something like:
Class.forName("net.sourceforge.jtds.jdbc.Driver"); // initialise the driver
String url = "jdbc:jtds:sqlserver://localhost:1433/myfirstdb";

Here's an extract from your code:
} catch (Exception e) {
System.out.println("Couldnt get connection");
}
You should never suppress exceptions as long as you don't understand its cause. Replace it by at least:
} catch (Exception e) {
System.out.println("Could not get connection");
e.printStackTrace();
}
Or maybe
} catch (Exception e) {
throw new RuntimeException("Could not get connection", e);
}
Either way, you should see the exception type, message and trace. In your code snippet the possible exceptions are ClassNotFoundException and SQLException. The first one would mean that the driver is not properly placed in the classpath. The second one would mean that connection cannot be obtained. The exception message and/or trace should tell in detail about the underlying root cause of the problem.
You should always observe exceptions. They tell something about the cause of the problem. You know, once a cause is understood, the solution is nothing more than obvious :)
See also:
Short MySQL/JDBC tutorial - Contains explanation about exception causes.
Further,
Can anyone tell me wat is meant by URL in the below line?
An URL is an Uniform Resource Locator. It's a common way to locate (identify) unique resources in computer systems and networks. The URL syntax for the MySQL database is explained in the documentation of the JDBC driver.
Can you tell me wat is the purpose of MySQL Connector/J?
It's the JDBC driver. The JDBC API exist of almost only interfaces. The DB vendors should provide their own concrete JDBC API implementation, which is the JDBC driver. With a JDBC driver you'll be able to connect a specific database using JDBC API.

If its MS SQL Server,
String driver = "com.microsoft.jdbc.sqlserver.SQLServerDriver";
Class.forName(driver);
String url = "jdbc:microsoft:sqlserver://host:1433/database";
Connection conn = DriverManager.getConnection(url, "username", "password");
For more info, see this to get started with Microsoft JDBC.
You can use any of the two JDBC drivers for MSSQL:
Microsoft SQL Server JDBC Driver
2.0
jTDS
For MS SQL Server driver 2.0, use
URL: jdbc:sqlserver://server:port; DatabaseName=dbname
Class name: com.microsoft.sqlserver.jdbc.SQLServerDriver
For MySql & Java, see this on SO.

You forgot a " at Class.forName(com.mysql.jdbc.Driver");
It should be
Class.forName("com.mysql.jdbc.Driver");

JDBC Connection Issue

I have create a getDBConnection method in my Java application. This returns a connection object, and hence I haven't closed this connection in this method itself.
Now, I am invoking this method from various methods in my application at regular intervals, and closing them inside a try - finally block. I thought this should free up the connection after use. However, I am seeing a large number of connections opened (about 50) in the MySQL Administrator's Server Connections tab.
//Defining a method to retrieve a database connection
// PropDemo is a properties class that retrieves Database related values from a file
public Connection getDBConnection() {
//Instantiating the Properties object
PropDemo prop = new PropDemo();
Connection con = null;
// Retrieving values from the parameters.properties file
String JdbcDriver = prop.getMessage("JdbcDriver");
String JdbcUrlPrefix = prop.getMessage("JdbcUrlPrefix");
String DBIP = prop.getMessage("DBIP");
String DBName = prop.getMessage("DBName");
String DBUser = prop.getMessage("DBUser");
String DBPassword = prop.getMessage("DBPassword");
try {
// Loading and instantiating the JDBC MySQL connector driver class
Class.forName(JdbcDriver).newInstance();
con = DriverManager.getConnection(JdbcUrlPrefix + DBIP + "/" + DBName, DBUser, DBPassword);
if (con.isClosed())
Logger.log("Connection cannot be established", "vm");
} catch (Exception e) {
Logger.log("Exception: " + e, "vm");
Logger.log(Logger.stack2string(e), "vm");
}
return con;
}
I am also closing the associated ResultSet and Statement Objects. What could be missing here?
I am planning to replace all the Statements with PreparedStatements for efficiency and security reasons. Will that help significantly? What else can be done?
EDIT:
This is just a core java application that is repeatedly quering for changes in some fields in a MySQL database through MySQL-JDBC connector. I am not using any framework like Spring or Hibernate.

Your code looks sane.
That's how you're creating a new connection.
Probably the error is where you close it.
You should close it in a finally block.
Some additional questions.
1) Are you sure those 50 conections come from this program ? Maybe there are some others comming from your same office. To confirm this you would need to stop the program, and look again in your connection monitor.
2) Does your application uses many connection simultaneously? Probably its a peak when you're using 50 at the same time.
If you can post the code where you close the connection. Chances are the problem is there.
Additionally I would suggest you to use a connection pool. You can build one your self or you can see the results from this page:
How many JDBC connections in Java?

Are you closing the connection object when you application closes as well?

Are you using your JDBC connection within a J2EE application server or with Hibernate?
Both of these tend to start out with a fairly high connection pool to begin with, so you would see a large number.
Check out the details on connection pooling.

You could take a Singleton approach to the problem and only create a new Connection object if the current one is null:
If (connectionObject != null){
return connectionObject;
}else {
//create new connection object
}
This will make sure that you only have one non-null connection at any time.