Drupal 7.x

I am using cck , profile2, computed field modules, i have created a profile where i added some hidden computed fields. One of the field is a sha1 hash of the time of signup. the filed name is field_data_field_hashed_id in the database. my question is how can get the uid of a user if i know only the hash id , i mean i need a sql statement to get the uid from the hash , is it possible ?

Let me know if its not clear

thanks

Can anyone help I cant seem to find a solution for this error when I login:

(I am learning to develop a theme from scratch.)

In my page.tpl.php, if I place this statement " print render($page['sidebar_first']); " in the end, I am getting some text displayed on the screen, the search text box and the search button.

My question: WHERE is all this coming from? I want to know which module/system element is putting in something in my "sidebar_first" region.

Uncaught exception thrown in session handler.

Just completed my first Drupal install (7.x) and I've themed it as well. Since this is for a small business website, I won't need anyone logging in to the site except for the administrator, yet I can't seem to find a way to remove the login panel from the home page of the site, or at least move the user login panel to another page. Is this possible to do?

How do I change the input size of site-wide contact form for Drupal 7? It is set at 60, and I want the input size changed to 30 because I want my contact form on the block. Any idea?