/* this will allow sidebar stretch vertically in right way */
html, body {
	min-height:100%;
	position: absolute; 
        width:100%;
}
 
/* stretching our sidebar */
#sidebar{
 width: 300px;
 height: auto;
 min-height:100%;
 position:absolute;
 background-color: #555;
}

To make content block is not to hard and you need is to set margin-left the same width as sidebar width

Conclusion:

• whatever your hoster says to you, you should aslo make back-ups by your own
• you should have some reserved hosting for such cases
• you should register your domain at another registrant instead of your hoster, to be able manage it by yourself even if your hoster is down
• you should use some service that will be checking “is your site up or down”, if it’s not – notify you (SMS, E-Mail)
• and the main one: don’t worry, everything can be fixed

I have a table with next columns: id, email, etc.

I need to calculate quantity of each e-mail domain, calculate percent of domain and sort this information.

Solution:

SELECT
    domain,
    total,
    (total / emailscount) * 100 AS domainpercentage
FROM
    (
        SELECT
        SUBSTRING_INDEX(email, '@', -1) AS domain,
        COUNT(contacts_list.id) AS total,
        (
            SELECT COUNT(cl.id)
            FROM contacts_list AS cl
        ) AS emailscount
        FROM contacts_list
        GROUP BY domain
        ORDER BY total DESC
    ) AS result

Explanation:
At first I select all domains and quantity of their entries.

SELECT
    SUBSTRING_INDEX(email, '@', -1) AS domain,
    COUNT(contacts_list.id) AS total,
    (
        SELECT COUNT(cl.id)
        FROM contacts_list AS cl
    ) AS emailscount
FROM contacts_list
GROUP BY domain
ORDER BY total DESC

Also I select amount of all entries in my table via inner query.

(
    SELECT COUNT(cl.id)
    FROM contacts_list AS cl
) AS emailscount

Then I wrap my query where I select inner`s query results and calculate percentage of each domain.

SELECT
    domain,
    total,
    (total / emailscount) * 100 AS domainpercentage
FROM
(...
) AS result

# increase memory up to 32 mb, if you need you can make this amount bigger

php_value memory_limit 32M

If this does not helps, then you should add this line to your .htaccess file:

php_value display_errors  ”1″

This will force PHP to show what error cause blank screen, and when you know problem it’s easy to find solution