private void rtrBtnActionPerformed(java.awt.event.ActionEvent evt) {
DefaultTableModel model = (DefaultTableModel) depTbl.getModel();
try{
Class.forName("java.sql.Driver");
Connection con = DriverManager.getConnection("jdbc:mysql://localhost/test1","admin","root");
Statement stmt = con.createStatement();
String query = "SELECT * FROM dept;";
ResultSet rs = stmt.executeQuery(query);
while(rs.next()){
String dno = rs.getString("deptno");
String dName = rs.getString("dname");
String lc = rs.getString("loc");
model.addRow(new Object[] {dno,dName,lc});
}
rs.close();
stmt.close();
con.close();
}
catch(Exception e){
JOptionPane.showMessageDialog(null,"Error In Connectivity");
}
}
Im trying to connect my JForm to the mysql database but not able to connect to the database, continuously executing catch statement "Error in Connectivity", please help how should i resolve this issue..............................................................................
Change the following line
Class.forName("java.sql.Driver");
to
Class.forName("com.mysql.jdbc.Driver");
in your code
This line of code is not correct - Class.forName("java.sql.Driver");
The java.sql.Driver is an interface. You need to provide the correct jdbc driver class for you appropriate db.
Such as for Oracle - Class.forName("oracle.jdbc.driver.OracleDriver");
Related
i'm trying a online database connection for my java application, but it seems my database isn't connected well this is my java code :
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here
try {
Class.forName("com.mysql.jdbc.Driver");
Connection con = DriverManager.getConnection("sql101.epizy.com/epiz_26206530_sekolah","LOGIN","PASSWORD");
String query = "select * from users where username=? and password=?";
PreparedStatement pst = con.prepareStatement(query);
pst.setString(1, jTextField1.getText());
pst.setString(2, jPasswordField1.getText());
ResultSet rs = pst.executeQuery();
if(rs.next()) {
JOptionPane.showMessageDialog(null, "Login Berhasil");
jLabel7.setText(rs.getString(1));
welcome well = new welcome();
this.setVisible(false);
well.setVisible(true);
}
} catch (Exception e) {
}
}
i already input MySQL JDBC Driver library, by the way i'm using online database from https://infinityfree.net/
I'm trying to display a list of the names of people in the database from the terminal, but not sure about how I would go about this. Right now I'm using a prepared statement
public static void showNames() throws SQLException {
Statement stmt=null;
Connection conn=null;
try {
conn = DriverManager.getConnection(DB_URL, USER, PASS);
stmt = conn.createStatement();
} catch (SQLException e) {
e.printStackTrace();
}
String selectTable="SELECT * FROM userInfo;";
stmt.execute(selectTable);
}
You're close.
Below code is not a complete answer, but hopefully enough to get you moving in the direction of obtaining a complete answer. The below code is basically the code you posted with some modifications.
public static void showNames() throws SQLException {
Statement stmt = null;
ResultSet rs = null;
Connection conn = null;
String selectTable="SELECT * FROM userInfo;";
try {
conn = DriverManager.getConnection(DB_URL, USER, PASS);
stmt = conn.createStatement();
rs = stmt.executeQuery(selectTable);
while (rs.next()) {
Object obj = rs.getObject("name of column in database table USERINFO");
System.out.println(obj);
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
if (conn != null) {
conn.close();
}
}
}
You didn't post the structure of database table USERINFO, so replace name of column in database table with the actual column name.
By the way, there are many examples of how to do this on the Internet, for example Processing SQL Statements with JDBC.
I am trying to validate a database (phpMyadmin) using Username and Password. I need to search in all the tables (25 tables in my database) for checking if the given username and password are present (Authentication) or not. Can anyone provide the query to search entire table using the given username and password?
Below is my code
public class Dbclass {
/**
* #param args
*/
Connection conn = null;
Statement statement = null;
ResultSet resultSet = null;
ResultSetMetaData metaData = null;
String DB_URL="com.mysql.jdbc.Driver";
String USER="java";
String PASS="redhat";
String username;
String password;
ResultSet rs;
public ResultSet dbConnection(String query)
{
//STEP 2: Register JDBC driver
try {
Class.forName("com.mysql.jdbc.Driver");
//STEP 3: Open a connection
System.out.println("Connecting to database...");
try {
conn = DriverManager.getConnection(DB_URL,USER,PASS);
//STEP 4: Execute a query
System.out.println("Creating statement...");
Statement stmt = conn.createStatement();
//sql = "SELECT username,password FROM Employees";
rs = stmt.executeQuery(query);
while(rs.next()){
//Retrieve by column name
username = rs.getString("user_name");
password = rs.getString("password");
//Display values
System.out.print("User_name: " + username);
System.out.print(",Password: " + password);
}
Authentication obj=new Authentication();
obj.userLogin(username,password);
//STEP 6: Clean-up environment
//rs.close();
//return rs;
stmt.close();
conn.close();
} catch (SQLException e) {
//TODO Auto-generated catch block
e.printStackTrace();
}
} catch (ClassNotFoundException es) {
//TODO Auto-generated catch block
es.printStackTrace();
}
finally{
//finally block used to close resources
try{
if(conn!=null){
conn.close();
}
if (rs != null) {
rs.close();
}
}catch(SQLException se){
se.printStackTrace();
}//end finally try
}//end try
return rs;
}
}
I guess you're looking for a where clause. Something like below.
SELECT username,password FROM Employees where username='usernm' and password='pwd'
If required, you can add UNION to merge more such queries, but not recommended due to performance issues.
i have a utility code to connect a database and to query a database. After calling the method to connect the database, i don't know how to call the method to query the table.
Here is the code to query:
public static ResultSet getData(Connection con){
ResultSet resultreport = null;
try{
PreparedStatement pmt = con.prepareStatement("SELECT NAME, AGE FROM EMPLOYEE");
resultreport = pmt.executeQuery();
System.out.println(resultreport.getString(1) + " " + resultreport.getString(2) );
} catch (SQLException e) {
e.printStackTrace();
}
return resultreport;
}
when i try this, i don't know what to insert the bracket:
Utility.getData(...);
Thank you for your help
You have to pass a connection object to the method.
for example.
Class.forName("com.mysql.jdbc.Driver");
Connection conn = null;
conn = DriverManager.getConnection("jdbc:mysql://hostname:port/dbname","username", "password");
Then call method
Utility.getData(conn);
I am trying to connect my android app to my postgresql database through jdbc, the login goes well but when i try run the query explotes and give me this error:
11-24 11:03:14.966: E/AndroidRuntime(673): at org.postgresql.jdbc2.AbstractJdbc2Statement.executeWithFlags(AbstractJdbc2Statement.java:403)
11-24 11:03:14.966: E/AndroidRuntime(673): at org.postgresql.jdbc2.AbstractJdbc2Statement.executeQuery(AbstractJdbc2Statement.java:283)
This is the code of the function that make the connection:
public void save_info(Element plate_info){
String retval = "";
try {
Class.forName("org.postgresql.Driver");
} catch (ClassNotFoundException e) {
e.printStackTrace();
retval = e.toString();
}
String url = "jdbc:postgresql://test.com:5432/test_db?user=adsfsdfasd&password=2222222";
Connection conn;
try {
DriverManager.setLoginTimeout(5);
conn = DriverManager.getConnection(url);
Statement st = conn.createStatement();
ResultSet rs = st.executeQuery("INSERT INTO order_tbl (custumer, _name, additional, ingredients_) VALUES('adsfasdf','asdfasdfasdf', 'asdfasdfasd', 'asdfasdfasdf', 'dasfasdf')");
while(rs.next()) {
retval = rs.getString(1);
}
rs.close();
st.close();
conn.close();
System.out.println(retval);
} catch (SQLException e) {
e.printStackTrace();
retval = e.toString();
}
}
You need to call executeUpdate, not executeQuery
int numRowsAffected = st.executeUpdate("INSERT INTO order_tbl (custumer, _name, additional, ingredients_) VALUES('adsfasdf','asdfasdfasdf', 'asdfasdfasd', 'asdfasdfasdf', 'dasfasdf')");
This is all you need.
DriverManager.setLoginTimeout(5);
conn = DriverManager.getConnection(url);
Statement st = conn.createStatement();
st.execute("INSERT INTO order_tbl (custumer, _name, additional, ingredients_) VALUES('adsfasdf','asdfasdfasdf', 'asdfasdfasd', 'asdfasdfasdf', 'dasfasdf')");
Here's a quick tutorial on how to use SQL Insert http://www.youtube.com/watch?v=Zto0PovkbKo