Thanks for your quick respond and your help. This is great. I have one more favor to ask you. As you know I am a beginner of PHP & Mysql, do I put that language on all my product pages? It seems to be too much work. Is there way that I can save main language that you wrote in to one file as "stock.php3", and point a link from product html page with known item number for "itemx"? And, print the result back to product html page with "Out of Stock" or "In Stock". I will appreciate your help. Thanks again for your help. Tony "Christopher Ostmo" <[EMAIL PROTECTED]> wrote in message 3B5858C3.22011.4C90352@localhost">news:3B5858C3.22011.4C90352@localhost... > 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 > Innovative Application Ideas > Meeting cutting edge dynamic > web site needs since the > dawn of Internet time (1995) > > Business Applications: > http://www.AppIdeas.com/ > > Open Source Applications: > http://open.AppIdeas.com/ -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] To contact the list administrators, e-mail: [EMAIL PROTECTED]
