Passing Query Strings - multiple fields - Help...

Anon

Greetings,
I have setup the php/mysql results page with the previous / next code. I am looking for a way to preserve the query string structure exactly as initial search with the offset value appended. I have not been able to locate any method to do this successfully.

Having a single field query is easy, the problem I am having is multiple field queries for refined searchs. Is there a way of capturing the query string value and preserving content?

db_results5.php3?Class_3=Keller+Charles&Class_4=Magnolia&Name=&Description=&offset=10

The problem I am having is that when I click the "Next" the previous query string is changed just a bit by the method I am currently using and the query retrieves all records in database. Also need ability for any number of query fields.

A feeble attemp....

$query = "Class_3=$Class_3";
$query .= "&Class_4=$Class_4";
$query .= "&Name=$Name";
$query .= "&Description=$Description";
$query .= "&Specials=$Specials";

Thankful for any help,
James

Anon

Shouldn't that say

...&query=something&offset=...

As it stands, your variable '$query' will be empty.

But you have to think carefull about this: just passing a complete
query string via the url can be quite a security risk: you have no
way of knowing some malicious user hasn't composed a rather
different query string and is submitting that instead, so you
will have to go to the trouble of parsing the query and seeing
if it's safe, and...

Are you using sessions? If so, you can just store the query
(and the offset, for that matter) as a session variable and
then the risk disappears.

Anon

Thanks Kirk,
Actually it is working to a degree, the query variables are passed from original db search to a degree. I am new at this, I did not take into consideration of the database being open to a security risk from just a query. What would be the best way to implement sessions?

Here is a sample of what I have so far on the results page, the search page just refers to this with form input for 4 or 5 queried fields.

Thanks,
James

<?php

$server = "localhost";
$user = " ";
$pass = " ";
$database = " ";
$conn = mysql_pconnect ($server,$user,$pass);
$select = mysql_select_db("$database")or die ("unable to select db");

// Start of Prev 123 Next code

$limit=10; // rows to return

$numresults=mysql_query("select * "."from TABLE
WHERE Class_1 LIKE '%$Class_1%'
AND Class_2 LIKE '%$Class_2%'
AND Class_3 LIKE '%$Class_3%'
AND Class_4 LIKE '%$Class_4%'
AND Cat_No LIKE '%$Cat_No%'
AND Name LIKE '%$Name%'
AND Description LIKE '%$Description%'
AND Specials LIKE '%$Specials%'
order by 1,20");

$numrows=mysql_num_rows($numresults);

// next determine if offset has been passed to script, if not use 0

if (empty($offset))
{
$offset=0;
}

// get results

$result=mysql_query("select * "."from TABLE
WHERE Class_1 LIKE '%$Class_1%'
AND Class_2 LIKE '%$Class_2%'
AND Class_3 LIKE '%$Class_3%'
AND Class_4 LIKE '%$Class_4%'
AND Cat_No LIKE '%$Cat_No%'
AND Name LIKE '%$Name%'
AND Description LIKE '%$Description%'
AND Specials LIKE '%$Specials%'
"."order by 1,20 limit $offset,$limit");

// now you can display the results returned

if ($row=mysql_fetch_array($result)){

// include code to display results as you see fit

do {
print ("

Output.....

");

} while($row = mysql_fetch_array($result));
} else {print "Sorry, no records were found!";}

$query = "Class_3=$Class_3";
$query .= "&Class_4=$Class_4";
$query .= "&Name=$Name";
$query .= "&Description=$Description";
$query .= "&Specials=$Specials";

// calculate number of pages needing links

$pages=intval($numrows/$limit);

print " <table width=600 cellspacing=1 cellpadding=2 border=0><tr><td BGCOLOR=#FBF5E7>   Search Result Pages      ";

// next we need to do the links to other results

if (($pages!=0 and $pages!=1) or ($pages==1 and ($numrows%$limit)))// If data <= 1 page skip all
{
if ($offset!=0)// bypass PREV link if offset is 0
{
$prevoffset=$offset-$limit;
echo "<a href=\"$PHP_SELF?$query&offset=$prevoffset\">PREV</a>   \n";
}

// $pages now contains int of pages needed unless there is a remainder from division

if ($numrows%$limit)// has remainder so add one page
{
$pages++;
}

for ($i=1;$i<=$pages;$i++) // loop thru and make links
{
$newoffset=$limit*($i-1);
If ($offset!=$newoffset) //Make a link only for other pages
{
echo "<a href=\"$PHP_SELF?$query&offset=$newoffset\">$i</a>   \n";
}
else
{
print "$i   \n";
}
}

// check to see if NEXT link is needed

if ($pages!=1 or (($pages==1 and ($numrows%$limit))))
{
if (($offset+$limit)<$numrows) // if last page skip NEXT link
{$newoffset=$offset+$limit;
echo "<a href=\"$PHP_SELF?$query&offset=$newoffset\">NEXT</a>\n";
}
}
}

print "</td></tr></table>";

Anon

Two comments.

(1) It looks like you've got this sequence:

  $numresults=mysql_query("select * "."from TABLE ...
...
$numrows=mysql_num_rows($numresults);
...
  // get results

  $result=mysql_query("select * "."from TABLE // exact same query

This is pure overhead--there's no reason to run the query twice. You can just count the rows returned by the real query you're actually going to use for the display.

(2) The script next says:

  // now you can display the results returned

  if ($row=mysql_fetch_array($result))

but this is not, strictly speaking, correct. If the query should fail for some reason (I don't mean that it's a valid query that merely ends up matching no records, but one that is actually invalid for some [accidental] reason), you'll never know it. That's a result of using $result without testing its value to see if it's true or not.

Anon

Thanks Kirk,
Are there any ideas to implement the sessions to resolve the next page search string bug. That is the most important issue at this time.

Thanks again,
James

Anon

I am trying to pass variables thru sessions, I successfully passed and saved thru session_register. The problem now is I am not sure how to delete variables prior to the next query. Using session_unset(); does the job nicely but it has to reside on the same results page and as long as the code is posted it disables the session_register from saving variables.

Any idea how to fix, much appreciated.

Thanks,
James