Stay Informed
Take a look at this script.
<html>
<body>
<?php
$db = mysql_connect("localhost", "root");
mysql_select_db("mydb",$db);
$result = mysql_query("SELECT * FROM employees",$db);
if ($myrow = mysql_fetch_array($result)) {
echo "<table border=1>\n";
echo "<tr><td>Name</td><td>Position</td></tr>\n";
do {
printf("<tr><td>%s %s</td><td>%s</tr>\n", $myrow["first"], $myrow["last"],
$myrow["address"]);
} while ($myrow = mysql_fetch_array($result));
echo "</table>\n";
} else {
echo "Sorry, no records were found!";
}
?>
</body>
</html>
There are a number of new features introduced here, but they're quite simple. First, there's the
mysql_fetch_array() function. This is exactly the same as mysql_fetch_row() with one nice exception:
Using this function, we can refer to fields by their names (such as $myrow["first"]) rather than their
numbers. This should save us some headaches. We've also introduced a do/while loop and an if-else
statement.
The if-else statement says that if we can assign a row to $myrow, then continue; otherwise skip to the
else section and do what's in there.
The do/while loop is a variation of the while() loop we used on the last page. We need the do/while loop
here for a very good reason: With the initial if statement, we assigned the first row returned by the query
to the variable $myrow. If at this point we executed a regular while statement (such as while ($myrow =
mysql_fetch_row($result)), we'd be kicking the first record out of the variable and replacing it with the
second record. But the do/while loop lets us test the condition after the code has been run once. So
there's no chance of us accidentally skipping a row.
Finally, if there are no records returned at all, the statements contained in the else{} portion will be
executed. To see this portion in action, change the SQL statement to SELECT * FROM employees WHERE
id=6 or something else that will return no records.
Now let's extend this looping and if-else code to make one fancy-schmancy page. You're going to love it.
Posted in: PHP/MySQL Tutorial
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