processing an array using a for... loop

Anon

Hi All,

I havent had any luck finding an answer to this - hoping someone here can help.

I have a query which returns a number of rows of data (thats easy 🙂 ).

But what i need to do is prepare a number of "sections" if you like, of that data, and work with these sections one at a time.

the thing that will determine the actual "section" is a value which is stored in the field "feat_ID".

basically, what I want to know is... is it possible to do something like the following:

do {

.... blah blah stuff to do ....

}
while ($result['feat_ID'] = 1)

or something similar? each feature ID should return 1 or more rows, but I dont know if this will screw up if that feature category returns no results.

I also dont want to have to run 5 or 6 queries, selecting only the results for each feature ID.

does this make sense? can anyone shed some light on it?

thanks

hiasl

You could us a 2 dimensional array for this.

$query = "select * from table";
$result = mysql_fetch_array($query);
if (mysql_num_rows($query) > 0) {
while (row = mysql_fetch_array($result)) {

}
}

hiasl

Sorry, I hit the return key to early

You could us a 2 dimensional array for this.

$query = "select * from table";
$result = mysql_fetch_array($query);
if (mysql_num_rows($query) > 0) {
while (row = mysql_fetch_array($result)) {
$array[$row[feat_id]][] = $row;
}
}

By doing this you should get an array with the feat_id in the first dimension and the results in the second

you can now walk through the results by doing this

while ($layer1 = each($array)) {
while ($layer2 = each($layer1[1])) {
echo "feat_id: ".$layer2[1][feat_id]."<br>\n"
echo "whatever: ".$layer2[1][whatever]."<br>\n"
}
}

hope this helps
matthias