However...the most important programming language of all, and the one which makes the most money for those good at it, is SQL. Even the best-written programs are useless without being able to access data, and that access is frequently the biggest performance bottleneck. In many cases that access determines whether a program is worth writing. This is where knowledge of SQL becomes an extremely desirable commodity.
Here's a sample SQL query, which happens to be an actual query used on this board:
Code: Select all
$sql = 'SELECT u.user_id, u.username, u.user_email, u.user_lang, u.user_notify_type, u.user_jabber
FROM ' . (($topic_notification) ? TOPICS_WATCH_TABLE : FORUMS_WATCH_TABLE) . ' w, ' . USERS_TABLE . ' u
WHERE w.' . (($topic_notification) ? 'topic_id' : 'forum_id') . ' = ' . (($topic_notification) ? $topic_id : $forum_id) . "
AND w.user_id NOT IN ($sql_ignore_users)
AND w.notify_status = " . NOTIFY_YES . '
AND u.user_type IN (' . USER_NORMAL . ', ' . USER_FOUNDER . ')
AND u.user_id = w.user_id';
35 years ago, COBOL programmers oftentimes made more money than people several levels higher in their organization. This was because corporations ground to a halt if their data was not, or could not be, accessed. The same is true today. COBOL is the father of SQL, and if you look closely, many SQL queries have more than a passing resemblance to their ancient COBOL counterparts.
Several features of this board were made possible through customized SQL queries. The smilies in the Quick Reply. The first-post-text when you hover over a topic. The avatars in the memberlist. The Likes system. The skin selector. And much of the index page. The soon-to-be-unveiled homepage for this board uses customized SQL queries to create a Wordpress look, yet still be within phpBB3.
So take some time to look at the documentation for an SQL engine such as MySQL or SQLite. Learn how to create efficient databases and write efficient queries. Because if you do, you will be making several times more money than the guy who thought learning the "latest and greatest" was the ticket to a great job!