PHP/MySQL warnings about results - PHP

On Nov 21, 5:43 pm, bruno_guedesav <bruno_guede...@yahoo.com.br>
wrote:
> I've made a function to fetch all results as an array of result-
> arrays. Getting the result arrays is easy, via mysql_fetch_array, and
> function itself is quite simple, as follows:
>
> function db_query($db, $query)
> {
> $result = mysql_query($query, $db);
> $res_array = array();
>
> if ($result) //it is a search
> {
> while($data = mysql_fetch_array($result,MYSQL_ASSOC))
> array_push($res_array,$data);
> }
>
> return $res_array;
>
> }
>
> But there's a slight problem: when the query in question is an INSERT,
> UPDATE or DELETE query, PHP will show me a warning saying:
>
> Warning: mysql_fetch_array(): supplied argument is not a valid MySQL
> result resource in /home/grad/ccomp/06/guedesav/public_html/PbBlog/inc/
> db.php on line 28
> (line 28 is "while($data = mysql_fetch_array($result,MYSQL_ASSOC))")
>
> and havingthis warning on the HTML output leads to be impossible to
> use header() to, for instance, go back to the post removal page. Is
> there any way to know prior to fetching if my result is of and INSERT/
> UPDATE/DELETE instead of a SELECT query?

Hello, Bruno.

I don't think it is a good idea to include a fetch_array into a
db_query() type
of function, first of all. If you really want to do that, however,
then make a
db_select_query() function that will do that, and do the rest with a
db_query function.

If you really want to stick with the idea, or if you have already done
a lot of code
with this function, then try this - mysql_fetch_array() will return
FALSE if no rows
are available in the result. Put an 'at' sign in front of the name of
the function (like
@mysql_fetch_array(...)). This will prevent it from echoing any
warnings, and the function
should still return FALSE if 1. no rows are available in the result 2.
(probably) if the
resource argument isn't compatible with the fetch function.

I don't find it a good idea, though. For instance, I do it like this
(for different
db compatibility): I have a function db_query, which executes a query,
and have a function
db_fetch() which fetches a row from a result returned by db_query. Of
course, I don't use
exact function names db_fetch and db_query, but you got the point. So,
I don't use db_fetch
unless I know exactly that I gave a SELECT statement to db_query.

Generally, when writing functions, try to stick with their exact
purposes - if it's executing
a statement, then it should do only that. If it's fetching a result,
it should do only that. When
including one into another, sooner or later you'll have to write
another function that doesn't
include others and the code will get messy. A -function- should have
its -function- not -functions-.
This way the code is cleaner and more easily understood.

Cheers,
Darko

On Wed, 21 Nov 2007 08:43:08 -0800 (PST), bruno_guedesav wrote...
>
>I've made a function to fetch all results as an array of result-
>arrays. Getting the result arrays is easy, via mysql_fetch_array, and
>function itself is quite simple, as follows:
>
>function db_query($db, $query)
>{
> $result = mysql_query($query, $db);
> $res_array = array();
>
> if ($result) //it is a search
> {
> while($data = mysql_fetch_array($result,MYSQL_ASSOC))
> array_push($res_array,$data);
> }
>
> return $res_array;
>}
>
>But there's a slight problem: when the query in question is an INSERT,
>UPDATE or DELETE query, PHP will show me a warning saying:
>
>Warning: mysql_fetch_array(): supplied argument is not a valid MySQL
>result resource in /home/grad/ccomp/06/guedesav/public_html/PbBlog/inc/
>db.php on line 28
>(line 28 is "while($data = mysql_fetch_array($result,MYSQL_ASSOC))")
>
>and havingthis warning on the HTML output leads to be impossible to
>use header() to, for instance, go back to the post removal page. Is
>there any way to know prior to fetching if my result is of and INSERT/
>UPDATE/DELETE instead of a SELECT query?


I don't think you're suppose to use the mysql_fetch_array() function on INSERTs
since that function is intended to capture the results from a query, rather than
adding, deleting , or updating.

I normally use mysql_query() for INSERTS and there's a few other functions like
mysql_error and mysql_result you can use in conjunction with that.

Tom
--
NewsGuy Free Trial Accounts
Now a massive 20 Gigabytes of unrestricted downloads !
http://newsguy.com/

"bruno_guedesav" <bruno_guedesav@yahoo.com.br> wrote in message
news:e3845f5f-57a0-4e47-b43d-403060cec833@i37g2000hsd.googlegroups.com...
> I've made a function to fetch all results as an array of result-
> arrays. Getting the result arrays is easy, via mysql_fetch_array, and
> function itself is quite simple, as follows:
>
> function db_query($db, $query)
> {
> $result = mysql_query($query, $db);
> $res_array = array();
>
> if ($result) //it is a search
> {
> while($data = mysql_fetch_array($result,MYSQL_ASSOC))
> array_push($res_array,$data);
> }
>
> return $res_array;
> }
>
> But there's a slight problem: when the query in question is an INSERT,
> UPDATE or DELETE query, PHP will show me a warning saying:
>
> Warning: mysql_fetch_array(): supplied argument is not a valid MySQL
> result resource in /home/grad/ccomp/06/guedesav/public_html/PbBlog/inc/
> db.php on line 28
> (line 28 is "while($data = mysql_fetch_array($result,MYSQL_ASSOC))")

When I've had this problem, I've implemented error-trapping - which I
probably should have done to start with.
The way I do it is to code something that says "if result is not an array,
don't try to perform array functions on it".
Or in your case "if connection is false, don't try to query it".






>
> and havingthis warning on the HTML output leads to be impossible to
> use header() to, for instance, go back to the post removal page. Is
> there any way to know prior to fetching if my result is of and INSERT/
> UPDATE/DELETE instead of a SELECT query?

In our last episode,
<e3845f5f-57a0-4e47-b43d-403060cec833@i37g2000hsd.googlegroups.com>,
the lovely and talented bruno_guedesav
broadcast on comp.lang.php:

> I've made a function to fetch all results as an array of result-
> arrays. Getting the result arrays is easy, via mysql_fetch_array, and
> function itself is quite simple, as follows:

> function db_query($db, $query)
> {
> $result = mysql_query($query, $db);
> $res_array = array();

> if ($result) //it is a search
> {
> while($data = mysql_fetch_array($result,MYSQL_ASSOC))
> array_push($res_array,$data);
> }

> return $res_array;
> }

> But there's a slight problem: when the query in question is an INSERT,
> UPDATE or DELETE query, PHP will show me a warning saying:

These queries do not return a result resource. See the manual. You have to
test $result before attempt to fetch, or you have to use you function only
for queries that do return result resources. (See the manual.)

> Warning: mysql_fetch_array(): supplied argument is not a valid MySQL
> result resource in /home/grad/ccomp/06/guedesav/public_html/PbBlog/inc/
> db.php on line 28
> (line 28 is "while($data = mysql_fetch_array($result,MYSQL_ASSOC))")

> and havingthis warning on the HTML output leads to be impossible to
> use header() to, for instance, go back to the post removal page. Is
> there any way to know prior to fetching if my result is of and INSERT/
> UPDATE/DELETE instead of a SELECT query?

Yes. Sort of. You can read the manual to determine which mysql queries
return results. Of course in some cases even those that do have result
returns will have an empty result. You need to test it.

--
Lars Eighner <http://larseighner.com/> usenet@larseighner.com
Countdown: 425 days to go.

On Nov 21, 8:06 pm, Lars Eighner <use...@larseighner.com> wrote:
> In our last episode,
> <e3845f5f-57a0-4e47-b43d-403060cec...@i37g2000hsd.googlegroups.com>,
> the lovely and talented bruno_guedesav
> broadcast on comp.lang.php:
>
>
>
> > I've made a function to fetch all results as an array of result-
> > arrays. Getting the result arrays is easy, via mysql_fetch_array, and
> > function itself is quite simple, as follows:
> > function db_query($db, $query)
> > {
> > $result = mysql_query($query, $db);
> > $res_array = array();
> > if ($result) //it is a search
> > {
> > while($data = mysql_fetch_array($result,MYSQL_ASSOC))
> > array_push($res_array,$data);
> > }
> > return $res_array;
> > }
> > But there's a slight problem: when the query in question is an INSERT,
> > UPDATE or DELETE query, PHP will show me a warning saying:
>
> These queries do not return a result resource. See the manual. You have to
> test $result before attempt to fetch, or you have to use you function only
> for queries that do return result resources. (See the manual.)
>
> > Warning: mysql_fetch_array(): supplied argument is not a valid MySQL
> > result resource in /home/grad/ccomp/06/guedesav/public_html/PbBlog/inc/
> > db.php on line 28
> > (line 28 is "while($data = mysql_fetch_array($result,MYSQL_ASSOC))")
> > and havingthis warning on the HTML output leads to be impossible to
> > use header() to, for instance, go back to the post removal page. Is
> > there any way to know prior to fetching if my result is of and INSERT/
> > UPDATE/DELETE instead of a SELECT query?
>
> Yes. Sort of. You can read the manual to determine which mysql queries
> return results. Of course in some cases even those that do have result
> returns will have an empty result. You need to test it.
>

I've tried it, I read the manual, but anyway it will go into the loop,
so it's just useles...

I guess I'll try the "@" to supress error messages(that's what I was
looking for, by the way); if it doesn't go well, there's always time
to spli the function in two.

Anyways, thank you all for the help!

bruno_guedesav wrote:
> On Nov 21, 8:06 pm, Lars Eighner <use...@larseighner.com> wrote:
>> In our last episode,
>> <e3845f5f-57a0-4e47-b43d-403060cec...@i37g2000hsd.googlegroups.com>,
>> the lovely and talented bruno_guedesav
>> broadcast on comp.lang.php:
>>
>>
>>
>>> I've made a function to fetch all results as an array of result-
>>> arrays. Getting the result arrays is easy, via mysql_fetch_array, and
>>> function itself is quite simple, as follows:
>>> function db_query($db, $query)
>>> {
>>> $result = mysql_query($query, $db);
>>> $res_array = array();
>>> if ($result) //it is a search
>>> {
>>> while($data = mysql_fetch_array($result,MYSQL_ASSOC))
>>> array_push($res_array,$data);
>>> }
>>> return $res_array;
>>> }
>>> But there's a slight problem: when the query in question is an INSERT,
>>> UPDATE or DELETE query, PHP will show me a warning saying:
>> These queries do not return a result resource. See the manual. You have to
>> test $result before attempt to fetch, or you have to use you function only
>> for queries that do return result resources. (See the manual.)
>>
>>> Warning: mysql_fetch_array(): supplied argument is not a valid MySQL
>>> result resource in /home/grad/ccomp/06/guedesav/public_html/PbBlog/inc/
>>> db.php on line 28
>>> (line 28 is "while($data = mysql_fetch_array($result,MYSQL_ASSOC))")
>>> and havingthis warning on the HTML output leads to be impossible to
>>> use header() to, for instance, go back to the post removal page. Is
>>> there any way to know prior to fetching if my result is of and INSERT/
>>> UPDATE/DELETE instead of a SELECT query?
>> Yes. Sort of. You can read the manual to determine which mysql queries
>> return results. Of course in some cases even those that do have result
>> returns will have an empty result. You need to test it.
>>
>
> I've tried it, I read the manual, but anyway it will go into the loop,
> so it's just useles...
>
> I guess I'll try the "@" to supress error messages(that's what I was
> looking for, by the way); if it doesn't go well, there's always time
> to spli the function in two.
>
> Anyways, thank you all for the help!

You need to split this function... for UPDATE, DELETE, etc.
mysql_query returns TRUE on success and FALSE on error. You get your
loop because your query was performed successfully. Re-read the page at:
http://us.php.net/manual/en/function.mysql-query.php
under 'RETURNED VALUES'

Norm

> Warning: mysql_fetch_array(): supplied argument is not a valid MySQL
> result resource in /home/grad/ccomp/06/guedesav/public_html/PbBlog/inc/
> db.php on line 28
> (line 28 is "while($data = mysql_fetch_array($result,MYSQL_ASSOC))")
>
> and havingthis warning on the HTML output leads to be impossible to
> use header() to, for instance, go back to the post removal page. Is
> there any way to know prior to fetching if my result is of and INSERT/
> UPDATE/DELETE instead of a SELECT query?

withour talking abut the SQL problem - see the other guys it should be
possible to prvent the error message with


$data = @mysql_fetch_array($result,MYSQL_ASSOC))

I do not know whether it is working with
mysql_fetch_array($result,MYSQL_ASSOC))
but it is working with @mysql_query and @mysql_num_rows

Regards Knut

On 22 nov, 14:57, Knut Krueger <knut.krue...@usa.com> wrote:
> > Warning: mysql_fetch_array(): supplied argument is not a valid MySQL
> > result resource in /home/grad/ccomp/06/guedesav/public_html/PbBlog/inc/
> > db.php on line 28
> > (line 28 is "while($data = mysql_fetch_array($result,MYSQL_ASSOC))")
>
> > and havingthis warning on the HTML output leads to be impossible to
> > use header() to, for instance, go back to the post removal page. Is
> > there any way to know prior to fetching if my result is of and INSERT/
> > UPDATE/DELETE instead of a SELECT query?
>
> withour talking abut the SQL problem - see the other guys it should be
> possible to prvent the error message with
>
> $data = @mysql_fetch_array($result,MYSQL_ASSOC))
>
> I do not know whether it is working with
> mysql_fetch_array($result,MYSQL_ASSOC))
> but it is working with @mysql_query and @mysql_num_rows

Oh, yes, it worked, indeed. There's no problem for me to have a single
entrance on the loop because of the first obligatory fetch as long as
it goes away cleanly so I can use headers afterwards, so this thread
is ended for me.

..oO(Knut Krueger)

>withour talking abut the SQL problem - see the other guys it should be
>possible to prvent the error message with
>
>
>$data = @mysql_fetch_array($result,MYSQL_ASSOC))
>
>I do not know whether it is working with
>mysql_fetch_array($result,MYSQL_ASSOC))
>but it is working with @mysql_query and @mysql_num_rows

Using '@' is really bad style in most cases. It suppresses the error
message instead of fixing it.

Micha