Help on getting multiple POSTS in php

pedroteixeira07

Hi there, I'm having two big issues to achieve my objective.

1st Issue:

I have an external source that allows a user to insert 0 or more keywords which are posted to a PHP file with this names: keyword0, keyword1, keyword2, etc... How do I get this files in PHP ?
I know if it was just one keyword I could retrieve it like this:
Syntax:

$keyword=$_POST[keyword];

But in this case it can be 0, just 1 or "infinite" keywords. Can you help me please?

2nd Issue:

Once I have this keyword values ''stored'' in php variables e.g. ($keyword0, $keyword1, etc) I need to make a query to my DB with this multiple possible keywords. I already have an N-to-N relationship set. It's something like this:

Picture
P_ID Pic
1 LA.jpg
2 NY.jpg
3 MI.jpg
4 SE.jpg
5 DA.jpg

Keywords
K_ID Keywords
1 beach
2 sun
3 cold
4 hot
5 sea

PicKey
PK_ID P_ID K_ID
1 1 1
2 1 2
3 1 4
4 1 5
5 2 3
5 2 5

I know for example for one keyword it would be something like :
Syntax:

mysql_query("SELECT P.Pic FROM Picture P, Keywords K, PicKey PK WHERE P.P_ID=PK.P_ID AND K.K_ID=PK.K_ID AND K.Keyword="beach"

But how about for multiple keywords ? Which can be one or more depending on the number of keywords posted by the user.

I would really appreciate some help with this. Everything is blury for me know. I don't have enough knowledge to complete this.
Thank you very much

mrbaseball34

Did you try to explode it?

pedroteixeira07

No, I'm sorry, I'm not familiar with that 🙁 I'll try to search about it

pedroteixeira07

So, something like this:

<?php
$keyword = $_POST[keyword];
$pieces = explode(" ", $keyword);
?>

Would give me all my keywords, being the first $pieces[0], the second $pieces[1] ?

Did I understood correctly ?

bradgrafelman

For your first issue, do you have any control over how the data is submitted? Rather than name form elements like "keyword0", "keyword1", etc., it'd be easier to name them all "keyword[]" so that $_POST['keyword'] is an array.

If you can't get this changed, then you could do something like the following to make an array:

for($keywords = array(), $i = 0; isset($_POST["keyword$i"]); $i++)
    $keywords[] = $_POST["keyword$i"];

Then, for issue #2, rather than doing a strict comparison, check if the keyword matches any in the given list, e.g. using MySQL's IN() syntax.

pedroteixeira07

Hello again, Thanks for your answers.

Just a simple question. I have $keywords as an array already.

when I implode it like this:

$keywordlist = implode(',', $keywords);

Does the IN statment in SQL accepts Strings in this format? ( value1, value2, etc )
Or does it need to be ('value1','value2','etc')?

In that case is it possible to implode like this?

$keywordlist = implode('','', $keywords);

Thank you
(I don't have anything set to Test this code, it will come from an Android application which is still not working)

bradgrafelman

pedroteixeira07;10951817 wrote:
Does the IN statment in SQL accepts Strings in this format? ( value1, value2, etc )
Or does it need to be ('value1','value2','etc')?

The IN statement doesn't modify the behavior of data types, so strings must still be delimited with quotes.

pedroteixeira07;10951817 wrote:
In that case is it possible to implode like this?
$keywordlist = implode('','', $keywords);

Exactly like that? No, since you have a parse error in there (unescaped single quotes). That's the general idea, though, yes; you'll also have to add the beginning and ending quote, e.g.:

$sql = " .. WHERE foo IN ('" . implode("','", $myvar) . "')";

pedroteixeira07;10951817 wrote:
(I don't have anything set to Test this code, it will come from an Android application which is still not working)

That doesn't mean you can't test it locally in a normal browser, though, does it?

EDIT: Also, don't forget that you should never place user-supplied data directly into a SQL query string, else you'll be vulnerable to SQL injection attacks (and/or just plain SQL errors). I was merely giving an example of the basic method you should use - my code snippets assume that you've already done some error handling (e.g. check for no keywords posted, in which case there probably isn't a need to even execute the SQL query) as well as data sanitization.

pedroteixeira07

Thank you very much! 😃

Indeed it doesn't mean that, but I would have to create some sort of form to do the same kind of posting which would probably bring me more questions lol But your right! Thank you very much for your help 😉

pedroteixeira07

Hi again, the syntax is giving me an error.. can someone help me with this implode thing?

Here is the code:

$keyword = $_POST['keyword'];

And my database query:

$data = "SELECT SP.ServicePic_ID, SP.ServicePic FROM Service_Pic SP, Keyword K, SPKeywords SPK, Date D WHERE SP.ServicePic_ID=SPK.ServicePic_ID AND SPK.Keyword_ID=K.Keyword_ID AND SP.Date_ID=D.Date_ID AND D.Date BETWEEN '$date1' AND '$date2' AND K.Keyword IN ('" . implode("','", $keyword) . "')";

Finally, my error:
implode() [<a href='function.implode'>function.implode</a>]: Invalid arguments passed in /home/pedrotei/public_html/thennnow/UT2.php on line 23 
Could not run query!You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ')'

bradgrafelman

Perhaps $keyword isn't an array? Do a [man]var_dump/man on it and paste the output.