Help building / using array

Posted on 16th Feb 2014 07:03 pm by admin

First - this is a cross-posting, if this is wrong I apologise! What started out as a MySQL query question (original post http://www.phpfreaks.com/forums/index.php/topic,273323.0.html) has become a PHP coding question....

I have 2 tables - docs and doc_relationships: -

+-------------+--------------+---Table: docs-----+-----------+---------------------+---------+
| document_id | doctype | location | title | thumbnail | added | visible |
+-------------+--------------+-----------+-------+-----------+---------------------+---------+
| 1 | instructions | pdf/a.pdf | a | img/a.jpg | 2001-04-12 20:16:58 | Y |
+-------------+--------------+-----------+-------+-----------+---------------------+---------+
| 2 | pressrelease | pdf/b.pdf | b | img/b.jpg | 2002-04-09 20:18:33 | Y |
+-------------+--------------+-----------+-------+-----------+---------------------+---------+
| 3 | newsletter | pdf/c.pdf | c | img/c.jpg | 2003-05-21 11:18:54 | Y |
+-------------+--------------+-----------+-------+-----------+---------------------+---------+
| 4 | instructions | pdf/x.pdf | x | img/x.jpg | 2004-01-22 19:13:21 | Y |
+-------------+--------------+-----------+-------+-----------+---------------------+---------+
| 5 | pressrelease | pdf/y.pdf | y | img/y.jpg | 2005-02-17 17:11:17 | Y |
+-------------+--------------+-----------+-------+-----------+---------------------+---------+
| 6 | instructions | pdf/z.pdf | z | img/z.jpg | 2006-07-02 12:15:58 | Y |
+-------------+--------------+-----------+-------+-----------+---------------------+---------+
| 7 | pressrelease | pdf/p.pdf | p | img/p.jpg | 2002-03-01 18:31:26 | Y |
+-------------+--------------+-----------+-------+-----------+---------------------+---------+


+-------Table: doc_relationships-----+
| rel_id | document_id | product_id |
+--------+--------------+------------+
| 1 | 1 | 4 |
+--------+--------------+------------+
| 2 | 2 | 3 |
+--------+--------------+------------+
| 3 | 4 | 3 |
+--------+--------------+------------+
| 4 | 6 | 2 |
+--------+--------------+------------+
| 5 | 7 | 3 |
+--------+--------------+------------+

Each row in the doc_relationships table ties one document to a product_id (product_ids are held in another table and will be hardcoded), the above example gives: -

doc 1: instructions, product 4
doc 2: pressrelease, product 3
doc 3: newsletter
doc 4: instructions, product 3
doc 5: pressrelease
doc 6: instructions, product 2
doc 7: pressrelease, product 3

Each product can have any number of Instructions, Press Releases and Newsletters related to it.
Press Releases and Newsletters can be related to one or more product.
Instruction manuals are usually related to one product only.

So far I have three pages - newsletters, pressreleases and instructions, which simply list all the matching documents, using this query: -

Code: $query="SELECT * FROM docs WHERE doctype='newsletter' AND visible='Y' ORDER BY added DESC, document_id DESC";

The problem is I also want to list any relevant documents on product pages, under headings referrring to doc types, so for example on product 3's page: -

-----------------------------------------------------------------------------------------
Product #3 - Super Widget

Desription - this is a remarkable widget, you'll wonder how you ever managed without one!

Instructions:
(link to doc 4)

Press Releases: -
(link to doc 2)
(link to doc 7)
-----------------------------------------------------------------------------------------

The query I'm using for the product pages is as follows: -

Code:
$query="SELECT * FROM docs, doc_relationships WHERE doc_relationships.document_id=docs.document_id AND doc_relationships.product_id='3' AND visible='Y' ORDER BY docs.added DESC, docs.document_id DESC";


I could add another condition to this query for "doctype" and do it 3 times, once for each doctype, but ideally what I'd like to do on a product page is create 3 arrays (newsletters, pressreleases & instructions) containing the details of each for that product (if any). So here's what I have so far: -

Code: // connect to database and issue the query
mysql_connect($server,$dbusername,$dbpassword);
@mysql_select_db($db_name) or die( "Unable to select database");
$query="SELECT * FROM docs, doc_relationships WHERE doc_relationships.document_id=docs.document_id AND doc_relationships.product_id='3' AND visible='Y' ORDER BY docs.added DESC, docs.document_id DESC";
$all_documents=mysql_query($query);
$total_docs=mysql_num_rows($all_documents);
mysql_close();

if ($total_docs != 0) {
while ($sql = mysql_fetch_object($all_documents)) {
if ($sql -> doctype=='newsletter'){
echo 'document #' . $sql -> document_id . ' is a newsletter<br />';
// create the newsletters array if it doesnt exist
if (!is_array($newsletters)) $newsletters= array();
// add to newsletters array;
array_push($newsletters, $sql);
} else if ($sql -> doctype=='pressrelease'){
echo 'document #' . $sql -> document_id . ' is a pressrelease<br />';
// create the pressreleases array if it doesnt exist
if (!is_array($pressreleases)) $pressreleases= array();
// add to pressreleases array;
array_push($pressreleases, $sql);
} else if ($sql -> doctype=='instructions'){
echo 'document #' . $sql -> document_id . ' is instructions<br />';
// create the instructions array if it doesnt exist
if (!is_array($instructions)) $instructions array();
// add to instructions array;
// not quite sure how!
array_push($instructions, $sql);
}
}
}

print_r($instructions);

As you can see, I added some test echos and this works as expected. The result of the final print_r($instructions) command is: -

QuoteArray ( => stdClass Object ( [document_id] => 4 [doctype] => instructions [location] => pdf/x.pdf [title] => x [thumbnail] => img/x.jpg [added] => 2004-01-22 19:13:21 [visible] => Y [rel_id] => 3 [product_id] => 3 ) ) The problem is I can't seem to extract the data from this array individually, for example I thought: -

Code: echo $instructions[0]['document_id'];

would echo '4' but it doesn't (and actually stops the page output dead).

So: -

1) Am I inserting results into the arrays correctly?

2) How do I access individual document info from each array?

3) How do I (for each array) loop through all documents?

Your Answer:

Login to answer

Other forums

How to show next and prev records
Hi all,

Sorry if this is simple, i'm very new to php, well, any programming language actually

Problem with PHP code- simple contact form
I'm relativily new to PHP; I know HTML and CSS stuff but I have a problem- I have a contact form wit

Using the $_GET variable to view certain records
Hello,

First let me explain my problem, I have 2 pages the first page pull a list of Guide ti

Xacute search within SQL results
I have a query that is pulling data, and I want to return a specific value from the results of that

help retrieiving results and doing pagination
Having some trouble trying to get the results to show on more than just one page.

What is ha

How to use Ajax to verify data on a DB ?
Hello everyone, well i want to know how to check a value if it exists or not on a Data base and capt

Help me with some material on Open Text Overview.
Hi Experts,
Please help me out with some material on Open Text. I have been supporting AP Workf

Best PHP Documentation generator
Hello guys!

I would like to hear from you what is the best PHP documentation generator. Perso

Having a problem get the selected item from a drop down menu
I have been looking at this for days now.

I have a drop down menu that get it's values from a

PHP Display Telephone Number On Referrer
I have used the php below to show a different telephone number in the header of the site depending u