Tony pressed the little lettered thingies in this order...
> I am trying to figure out how to read data base(Mysql) with rows of item
> number (item) and quantity, so that when item number was given, it searched
> for the quantity of the item number. If the quantity number is 0 or less,
> it will show "Out of Stock", else will show "In Stock" on my web page. Here
> is part of language that I wrote and didn't work. Please help me what to
> do,
>
There are two common methods. One uses PHP and the other uses
MySQL. The one that is most efficient depends largely on the design
and size of the table and the desired output. See below...
> $result = mysql_query("SELECT * FROM inventory",$link);
>
Here are the two queries that will work. The first with PHP:
$result = mysql_query("SELECT * FROM inventory WHERE item =
'$itemx'",$link);
$num = mysql_num_rows($result);
if ($num < 1) {
echo "Out of stock";
} else {
echo "In stock";
}
This would be very inneficient because it requires MySQL to do a full
retrieval from the table. The only reason you would want to do it this way
is if you wanted to relace the "In stock" above with actual results from
the query.
If you just wanted to say "In stock" it would be more efficient to use
MySQL's built-in COUNT(*) function:
$result = mysql_query("SELECT COUNT(*) FROM inventory WHERE
item = '$itemx'",$link);
while ($row = mysql_fetch_row($result)) {
$num = $row[0];
}
if ($num < 1) {
echo "Out of stock";
} else {
echo "In stock";
}
Note that if you use mysql_num_rows() on the second query, you will
always get a result of one (1) because the number of rows that MySQL
returns with this query will always be one (it returns how many records
matched your query as its one row return), assuming that there are no
errors. In either case, you can echo $num to display the number of
records returned.
Good luck...
Christopher Ostmo
a.k.a. [EMAIL PROTECTED]
AppIdeas.com
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