Lost Drupal node content

Question

A Drupal site a friend has on my server (WHM/CPanel) show his menu navigation on the left but the links go to the Welcome to your new site screen.
I think he must have tried to upgrade Drupal. How to I resync the navigation so /node/15 points to his actual content?

EDIT MySQL was updated yesterday and then my friend called today to say his Drupal site was broken. I was away from my computer so I asked my brother in law to help since he new Drupal better than I. I'm not sure exactly everything the two of them did but it looks like they upgraded to a newer Drupal or tried to upgrade because when you browse to his site, it shows the standard

 Welcome to your new Drupal website!
 Please follow these steps to set up and start using your website:

But all his menu navigation (I guess they are nodes?) are displayed but when you click any one of those links, it just goes to the same default `Welcome to your Drupal site'

Answer 1

I solved my problem. I noticed the node_revisions table in the database had all the content entries. But there were no corresponding entries in the node table. Through the main site I added some content and noticed the entries made in both those tables. I made note of the format. I then inserted records accordingly into the nodes table and whola all content appeared when I clicked the menu links.

I did a bulk SQL load using phpMyAadmin

INSERT INTO `node` (`nid`, `vid`, `type`, `title`, `uid`, `status`, `created`, `changed`, `comment`, `promote`, `moderate`, `sticky`) VALUES
(1, 1, 'page', 'zzxxzz', 1, 1, 1329017099, 1329017449, 0, 0, 0, 0),
(2, 2, 'page', 'zzxxzz', 1, 1, 1329017099, 1329017449, 0, 0, 0, 0),
(3, 3, 'page', 'zzxxzz', 1, 1, 1329017099, 1329017449, 0, 0, 0, 0),
(4, 4, 'page', 'zzxxzz', 1, 1, 1329017099, 1329017449, 0, 0, 0, 0),
(5, 5, 'page', 'zzxxzz', 1, 1, 1329017099, 1329017449, 0, 0, 0, 0),

etc... up to the total number of nodes listed in the node_revision table

I had 141 nodes.

Answer 2

节点修订表具有写入脚本以将数据导入节点表的所有内容。