Getting a table of database based on user type in the login form

Getting a table of database based on user type in the login form

i have a problem where i cannot solve it. So, i decided to post here my
problem is, probably you guys can help me out.
Well, here is my case: 1. i already can make a new table based on the
username that user type in the registration form and store it to the
database.
Here is my problem:
I want to when the user login through the login form, the database loaded
based on the username. For example: i created the table name: "Fuhans" at
the database, and when i login through the login form, i used the name
"Fuhans" as the username, and the database loaded based on the username
that i type (for now it is Fuhans).
Here is my question:
What happen and how do i make it happen if the user is different? For
example: the code of the OLEDBCommand is fixed "FROM [Fuhans]", and user
type different name in the username at the login form, this is the case
that whatever user type in the username at the login form, the database is
load "Fuhans" table. What i want is whatever the user type at the username
in the login form, the database is loaded based on the username.
Here is the link of the screenshot or the code that prove my case above:
1. Here and Here.
OleDbCommand cmd = new OleDbCommand("SELECT [Code] FROM ['" +
firstForm.textBox1.Text + "']", conn);
That code above doesn't work for me.. textBox1.Text is where the username
at the login form. What i have tried with the above code is, if the user
type "A" as the username, the program look at the database whether there
is table name "A" in the database, if it is valid (or there is), the
database load.
Thanks in advance!