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how to connect to mysql database ?

 
teja dharma
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hi friends i am new to jdbc .I want to connect my program to mysql5.0 database.
I compiled the below program from the c:\ drive. But at run time i am getting classnot found Exception:com.mysql.jdbc.Driver
and in the below program in the string dburl the hello is the database name which i created

import java.sql.*;
import javax.sql.*;
public class jdbcdemo
{

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
String dbtime;
String dbUrl = "jdbc:mysql://localhost:3306/hello";
String dbClass = "com.mysql.jdbc.Driver";
String query = "Select * FROM users";

try {

Class.forName("com.mysql.jdbc.Driver");
Connection con = DriverManager.getConnection (dbUrl);
Statement stmt = con.createStatement();
ResultSet rs = stmt.executeQuery(query);

while (rs.next()) {
dbtime = rs.getString(1);
System.out.println(dbtime);
} //end while

con.close();
} //end try

catch(ClassNotFoundException e) {
e.printStackTrace();
}

catch(SQLException e) {
e.printStackTrace();
}


}

}
 
srinivas srinivasmeenavalli
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Issue with com.mysql.jdbc.Driver classpath and Jar file.
MQSQL Driver class has to be in class path while executing your JDBC program.
Java databse connectivity jar contains interfaces like statement ,result set etc.
Each vendor will provide own implementation of JDBC . To execute oracle jdbc program you need to have jar file from oracle.
as i know above statment applies all of the databases.
here solutio is you have to include MQSQL Jar file in the classpath. Which IDE you are using ?
MYSQL Jar
All the Best
 
teja dharma
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srinivas srinivasmeenavalli wrote:Issue with com.mysql.jdbc.Driver classpath and Jar file.
MQSQL Driver class has to be in class path while executing your JDBC program.
Java databse connectivity jar contains interfaces like statement ,result set etc.
Each vendor will provide own implementation of JDBC . To execute oracle jdbc program you need to have jar file from oracle.
as i know above statment applies all of the databases.
here solutio is you have to include MQSQL Jar file in the classpath. Which IDE you are using ?
MYSQL Jar
All the Best


I compiled the program by setting the class path like this
javac jdbcdemo.java -classpath "C:\Documents and Settings\teja\MyDocuments\mysql-connector-java-5.1.10\mysql-connector-java-5.1.10.jar"
I mean jarfile is present in C:\Documents and Settings\teja\MyDocuments\mysql-connector-java-5.1.10\mysql-connector-java-5.1.10.jar at compile time no error but at run time i am getting nullpoinerexception
 
Vijitha Kumara
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teja dharma wrote: ...at compile time no error but at run time i am getting nullpoinerexception

Did you use the same set of required entries in the CLASSPATH when running as with compiling? Can you post the full stack trace?
 
teja dharma
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Vijitha Kumara wrote:
teja dharma wrote: ...at compile time no error but at run time i am getting nullpoinerexception

Did you use the same set of required entries in the CLASSPATH when running as with compiling? Can you post the full stack trace?

At compile time i used the command
javac jdbcdemo.java -classpath "C:\Documents and Settings\teja\MyDocuments\mysql-connector-java-5.1.10\mysql-connector-java-5.1.10.jar"

At runtime java jdbcdemo :
 
Vijitha Kumara
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teja tej wrote:At runtime java jdbcdemo :

No, you should provide the same set of jars used to compile when running too ("java -cp <setofJARs> classname").
 
teja dharma
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Vijitha Kumara wrote:
teja tej wrote:At runtime java jdbcdemo :

No, you should provide the same set of jars used to compile when running too ("java -cp <setofJARs> classname").

At runtime I gave the command java -cp "C:\Documents and Settings\teja\MyDocuments\mysql-connector-java-5.1.10\mysql-connector-java-5.1.10.jar" jdbcdemo
This time i got java.lang.NoClassDefFoundError:jdbcdemo
 
Vijitha Kumara
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teja tej wrote:At runtime I gave the command java -cp "C:\Documents and Settings\teja\MyDocuments\mysql-connector-java-5.1.10\mysql-connector-java-5.1.10.jar" jdbcdemo
This time i got java.lang.NoClassDefFoundError:jdbcdemo

When you use classpath switch you have to point all the classes/jars which are required to run the application, because default/classpath entry in environment is ignored. So in this case you should append the path to the "jdbcdemo" (and any other classes required) to the "classpath" switch as well.
 
Maneesh Godbole
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teja tej wrote:

Please check your private messages for an important administrative matter
 
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