May 2003
Intermediate to advanced
592 pages
14h 28m
English
Content preview from PHP and MySQL for Dynamic Web Sites: Visual QuickPro Guide
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Using mysql_num_rows()
The next logical function to discuss is mysql_num_rows(). This function returns the number of rows retrieved by a SELECT query, taking the query result as a parameter.
I’ll use this function in two different ways. First I’ll modify view_users.php to list the total number of registered users. Second, I’ll modify register.php to test if a username has already been taken.
To modify view_users.php:
1. | Open view_users.php (refer to Script 6.7) in your text editor.
|
2. | Before the if ($result) conditional (line 12), add this line (Script 6.9)
$num = mysql_num_rows ($result); |
3. | Change the original $result conditional to if ($num > 0) { The conditional ... |
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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