jdbc and mysql

[Divyajot Ahluwalia]

hi,
can someone pl tell me how to connect to mysql?
what is the driver? procedure to get it and install
what is the code required
thanks

[Sandeep Jain]

Hi,
To connect to the mysql database u hava to download a driver called "org.gjt.mm.mysql.Driver" .
For ur query i am writing a small peice code
DriverManager.registerDriver(new Driver());
String s = "jdbc:mysql://197.100.0.191:3306/test";
Class.forName("org.gjt.mm.mysql.Driver");
Connection con = DriverManager.getConnection(s);
Rest of the statement are same .

If u dont have the driver and if u dont get the driver on net mail me i will send u the file
------------------
Sandeep Jain

[Sandeep Jain]

I just forgot to mention that
the
1)first one is the ip address
2) test -> the database name
------------------
Sandeep Jain

[Thomas Paul]

Here is the generic connect to database code:

    public boolean connectToDatabase() throws IOException {
        
        InputStream is = getClass().getResourceAsStream("db.properties");
        
        try {
            dbProps.load(is);
        } catch (Exception e) {
            throw new IOException("Could not read properties file");
        }
        
        try {
            Class.forName(dbProps.getProperty("db.driver"));
        }
        catch (ClassNotFoundException e) {
            String reason = "Could not register JDBC driver.  Driver class name: " + e.getMessage();
            System.out.println(reason);                
            return false;          
        }
        catch (Exception e) {
            String reason = "Could not register JDBC driver.  Driver class name: " + e.getMessage();
            System.out.println(reason);
            return false;               
        }
        
        try {
            connection = DriverManager.getConnection(dbProps.getProperty("db.url"),
                    dbProps.getProperty("db.user"), dbProps.getProperty("db.password"));                
        }
        catch (Exception e) {
            String reason = "Could not connect to database.  Driver class name: " + e.getMessage();
            System.out.println(reason);
            return false;               
        }
        return true;
    }

This uses a file called db.properties that looks like this:

db.driver=org.gjt.mm.mysql.Driver
db.user=MyUserId
db.password=MyPassword
db.url=jdbc:mysql:MyDatabase

Customize the db.properties file for any database. Here is the example for JDBC-ODBC:

db.driver=sun.jdbc.odbc.JdbcOdbcDriver
db.user=MyUserId
db.password=MyPassword
db.url=jdbc:odbc:MyOdbcName

[This message has been edited by Thomas Paul (edited November 21, 2000).]

[Brian Snyder]

Hi Thomas,
I know that your message was posted a long time ago, but could you email me at [e-mail] to describe how you put the following into a .properties file. I've been trying this myself and have been experiencing some trouble with it. Thanks for your time.

db.driver=org.gjt.mm.mysql.Driver
                   db.user=MyUserId
                   db.password=MyPassword
                   db.url=jdbc:mysql:MyDatabase
How and where do I save this info????????

Brian

[Brian Snyder]

I actually answered my own question with thanks to long sun. I didn;t realize you had to actually set the properties using a properties file. Thanks!!

public static Connection getConnection()
            throws SQLException, IOException{ 
Properties props = new Properties();
   String fileName = "MakeDB.properties";
   FileInputStream in = new FileInputStream(fileName);
   props.load(in);
   String drivers = props.getProperty("jdbc.drivers");
if (drivers != null)
   System.setProperty("jdbc.drivers", drivers);
   String url = props.getProperty("jdbc.url");
   String username = props.getProperty("jdbc.username");
   String password = props.getProperty("jdbc.password");
   return
   DriverManager.getConnection(url, username, password);
 }

[Smilidon Sapiens]

Hi,
can anybody tell me the function of the line:
if (drivers != null)
System.setProperty("jdbc.drivers", drivers);
Why that line?
Thanks!

[David O'Meara]

The JDBC API is designed to run with any complient driver. When you ask JDBC for a connection to a database, the DriverManager needs to know which driver to get it from. It gets this information from the 'jdbc.driver' property stored in the Java System properties. (ie NOT the actual computer properties.)
There are (generally) two ways of defining a driver. The easiest is to call Class.forName("fully qualified driver name"). This makes it the driver's responsibility to register itself with JDBC and life goes on.
The other way is to define the driver name on the command line when executing the program using the -D<name>=<value> option.
(The code above provided by Thomas is equivalent to the first method)
A third method that I hadn't thought of is to simply write the driver name directly to the JVM properties, although I don't see any advantage over the Class.forName() method...
DOM

[Ken Shamrock]

Hi,
if after I compiled that servlet which works with DB, I delete the mysql???.bin copied to jdk1.4, can the Servlet still work? I've tried, it can. So basically this driver is only for compile?