Re: [PHP] using mysql_query() twice?
On Friday, January 11, 2002, at 05:42 PM, Nick Wilson wrote: > That's not it. Your first $result is a resource indicator (container for > results) so if you re-assign it (put another value into it) it becomes > useless as your while statement depends on it. (This may be redundant, but I'm hoping that someday someone will find this info in the archives as helpful:) Now I understand. I was mistaken in the way that I first conceptualized the following: $sql = "some SQL code"; $result = mysql_query($sql, $db); Originally, I thought that $result was just a variable that represented the function "mysql_query($sql, $db)". And when $result is called by, for instance, mysql_fetch_array(), in the form "mysql_fetch_array($result)", all I was really doing was making a more organized form of this: mysql_fetch_array((mysql_query($sql, $db))) But no! It appears that defining the variable $result like so: $result = mysql_query($sql, $db); Is actually performing an operation! The mysql_query() function happens at this time! Not during the mysql_fetch_array() as I previously thought. If what I have written above here is correct (and I hope it is) then you have helped me learn a fundamental element of the way PHP works, at least with this command. I had not been thinking of $result as a "container for results" before, rather as a "container for another function for later use". Awesome. Erik -- PHP General 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]
Re: [PHP] using mysql_query() twice?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 * On 11-01-02 at 23:39 * Erik Price said > > EXCELLENT! > It worked perfect. > So $result can't be used twice -- I wonder if it somehow is altered by > the mysql_fetch_array() that is performed upon it. That's not it. Your first $result is a resource indicator (container for results) so if you re-assign it (put another value into it) it becomes useless as your while statement depends on it. Happy to help :) - -- Nick Wilson Tel:+45 3325 0688 Fax:+45 3325 0677 Web:www.explodingnet.com -BEGIN PGP SIGNATURE- Version: GnuPG v1.0.6 (GNU/Linux) Comment: For info see http://www.gnupg.org iD8DBQE8P2pbHpvrrTa6L5oRAqWrAJ0RPOMtsW4IhBTkzKycyJnnZHwATACfTct6 Pi2wOViPXfXlpR1V3iw78Is= =RpGT -END PGP SIGNATURE- -- PHP General 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]
Re: [PHP] using mysql_query() twice?
EXCELLENT!
It worked perfect.
So $result can't be used twice -- I wonder if it somehow is altered by
the mysql_fetch_array() that is performed upon it.
Thanks Nick.
On Friday, January 11, 2002, at 05:23 PM, Nick Wilson wrote:
> I'll most likely be corrected (I just joined the list to brush up on my
> php) but I think that if you change this
>
>> while ($row = mysql_fetch_array($result) or die("You lose. No data
>
> to this
>
>> while ($row = mysql_fetch_array($another_result) or die("You
>> lose. No data
>
> You'll be on the right track.
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Re: [PHP] using mysql_query() twice?
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* On 11-01-02 at 23:08
* Erik Price said
> I am curious if using the same mysql_query() function twice causes some
> kind of problem.
>
> It seems that if I use
>
> $result = mysql_query($sql, $db);
> if (mysql_fetch_array($result)) {
> while ($row = mysql_fetch_array($result) or die("You lose. No data
> fetched.")) {
> // print some data
> // print a simple sentence to see if the WHILE statement even
> executes
> }
> } else {
> // print "No results match your criteria"
> }
>
>
> IF statement is true but the WHILE statement doesn't seem to produce its
> intended effect. In other words, I get the die() message "You lose. No
> data fetched."
I'll most likely be corrected (I just joined the list to brush up on my
php) but I think that if you change this
> while ($row = mysql_fetch_array($result) or die("You lose. No data
to this
> while ($row = mysql_fetch_array($another_result) or die("You lose. No data
You'll be on the right track.
> This leads me to believe that I can't run two instances of mysql_query()
> or perhaps mysql_fetch_array().
No, of course you can.
HTH
- --
Nick Wilson
Tel:+45 3325 0688
Fax:+45 3325 0677
Web:www.explodingnet.com
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