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ViewsHow to make the user see his own data after registration?
For example, I've got MySQL table with all users data
How to make after user sign in, he sees his own username?
I've tried this:
con = DriverManager.getConnection(url, user, password);
stmt = con.createStatement();
rs = stmt.executeQuery(query);
while (rs.next()) {
String name = rs.getString(1);
System.out.println("username : " + name);
}
But it just shows all usernames in MySQL table.
·
Santiago Trujillo
2 answers
Answer question0
Your query does not filter the rows of the table.
Use a WHERE clause:
String query = "select username from users where username = ?";
stmt.setString(1, user);
rs = stmt.executeQuery(query);
if (rs.next()) {
String name = rs.getString(1);
System.out.println("username : " + name);
} else {
System.out.println("No user : " + user);
}
The ? placeholder will be replaced by the value of the variable user properly quoted.
·
Santiago Trujillo
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0
String query = "select username from users";
to
String query = "select username from users where username = '"+user+"' ";
To avoid sql injections, it is advisable to use a PreparedStament. Check this link for more details: https://docs.oracle.com/javase/7/docs/api/java/sql/PreparedStatement.html
·
Santiago Trujillo
Report
Answer question