Fatal error: Call to a member function query() on a non-object

24hourcoder

Hello
I'm trying to show data from a table. However, when I do this, I get call to a member function query() on a non object. Here is my code.

<?php

$select = $select1->query('SELECT * FROM rcomments');
$meta = $select->getColumnMeta(0);
var_dump($meta);


?>

I actually don't know which variable it is referring to, but I tried setting them each one by one as global, but same error. Thanks in advance for your help.

Weedpacket

Since you're trying to call the [font=monospace]query[/font] method on [font=monospace]$select1[/font], that's the variable it's referring to. Apparently it doesn't contain an object. Why that should be depends on where it gets its value from.

24hourcoder

Ok I fixed it by putting it into a function. However, now I am trying to put this into an if else statement so if there are no comments, then the message wills how up stating so as in the echo below. Now I get the same error.

<?php

//show comments
function showcomments($select) {  

If ($select >= 0)  

 {
$show = $select->query("SELECT username, subject, contact, comment, date FROM comments WHERE page = ? ORDER BY time");
$show->execute(array($_SERVER['REQUEST_URL']));
$meta = $select->getColumnMeta(0);
var_dump($meta);

}


else
{ 
echo 'No comments yet.  Feel free to be the first!';

}
}

?>

That's what happens when I get inventive is I break it🙁

What am I missing? Thanks

bradgrafelman

24hourcoder;11031953 wrote:
Ok I fixed it by putting it into a function.

I doubt that. Moving code into a function won't change anything unless you inadvertently change something else (e.g. what you pass into the function when you call it).

24hourcoder;11031953 wrote:
What am I missing?

First thing that jumps out at me is that your if() statement is comparing $select with 0 as if the former is some sort of numeric value, yet you later attempt to use that same variable as if it held an object. That doesn't make any sense, so... what exactly is $select supposed to be here?

24hourcoder

Yes, I put parameters in the function.

Ok what you said about $select makes sense. $select is supposed to be the comments that will be put on page if they exist from mysql database. What I was trying to do, although now I know I was wrong, was say (in english:-) if there are comments (quantity greater than or equal to 0), show them. If not, say there are no comments.

How should I go about that instead?

NogDog

I'm not sure which database interface you are using, but there should be method for getting the number of rows returned, e.g.: rowCount() for PDO or the $num_rows variable for a MySQLi result object.

24hourcoder

NogDog;11031967 wrote:
I'm not sure which database interface you are using, but there should be method for getting the number of rows returned, e.g.: rowCount() for PDO or the $num_rows variable for a MySQLi result object.

Ok I'm using PDO. I looked at php.net for rowcount() and I'm wondering how to protect it from SQL injection attacks? Are you able to prepare/execute?

NogDog

There's no need to worry about injection: you're not using any external inputs.

$show->execute(array($_SERVER['REQUEST_URL']));
$numRows = $show->rowCount();

24hourcoder

Oh yea. Duh (to myself:-)
Thanks!

24hourcoder

Stil getting the fatal error call to a member function on line 7 though. If I must declare $select as a global (which I don't really want to do), how should I declare it since it is referring to the select statement?

<?php

//show comments
function showcomments($select) {  

If ($select >= 0)  

 {
$show = $select->query("SELECT username, subject, contact, comment, date FROM comments WHERE page = ? ORDER BY time");
$show->execute(array($_SERVER['REQUEST_URL']));
$numRows = $show->rowCount();
}
else
{ 
echo 'No comments yet.  Feel free to be the first!';

}
}

?>

Weedpacket

The comment by bradgrafelman still applies:

bradgrafelman wrote:
First thing that jumps out at me is that your if() statement is comparing $select with 0 as if the former is some sort of numeric value, yet you later attempt to use that same variable as if it held an object. That doesn't make any sense, so... what exactly is $select supposed to be here?

In your code you still compare it with 0, and then you try to use it as though it were supposed to be a PDO connection. So which is it?

24hourcoder

Sorry I got everything mixed up, old and new. I took the if out for now. I'm using PDO. Still getting the error. 🙁

<?php

//show comments
function showcomments($select) {  

$show = $select->query("SELECT username, subject, contact, comment, date FROM comments WHERE page = ? ORDER BY time");
$show->execute(array($_SERVER['REQUEST_URL']));
$numRows = $show->rowCount();
}


?>

bradgrafelman

How do you call the function? Show us the definition of the variable you pass in as the $select parameter.

24hourcoder

<?php

//show comments
function showcomments($select) {

$show = $select->query("SELECT username, subject, contact, comment, date FROM comments WHERE page = ? ORDER BY time");
$show->execute(array($_SERVER['REQUEST_URL']));
$numRows = $show->rowCount();
}

24hourcoder

Sorry. I do call the function in the other file like this.

<?php
showcomments($select);
?>

As for declaring the variable, I was wondering about that earlier. If I'm using it for the query to do the select statement, what do I need to declare it as? Originally I thought it was ok and what was in the select statement would go to it, then get passed to the first variable $show. But something is missing.

Weedpacket

Do you have a PDO connection to your database anywhere? That's what you should be using.

bradgrafelman

24hourcoder;11032039 wrote:
But something is missing.

Yep; a basic understanding of OOP programming.

If you don't declare $select (talking about the variable you're passing into showcomments() - not the parameter; note these are two completely separate entities) before you pass it into showcomments(), then you're trying to use an undefined variable. So rather than just blow up, PHP will 1) emit an error message, and 2) continue on as if you had passed in NULL instead. Thus, inside the function, you're trying to use the NULL value as if it were an object (namely, you're trying to call one of its methods named 'query').

24hourcoder

Ok. I wasn't sure "what" to declare it as since it will begin the array. So for testing, I declared it as 'a'. Still got error, and even when I declared it as a global got the error. I'm looking at a totally different example then what I'm donig though.

<?php

//show comments

$select = 'a';

function showcomments($select) {  

global $select;
$show = $select->query("SELECT username, subject, contact, comment, date FROM comments WHERE page = ? ORDER BY time");
$show->execute(array($_SERVER['REQUEST_URL']));
$numRows = $show->rowCount();
}


?>

I do have a connection to my database (no errors from it anyways🙂 and that is referenced in a seperate file and included into the main file, as is this function page I'm working on.

Weedpacket

You need to have the connection stored in [font=monospace]$select[/font], since that is what you're trying to send the query to.

24hourcoder

$select should connect or it should be passed througĥ function (db connection and $select)

Heres my connect code. Do I pass $conn and $select in the function? Or replace $cõnn with $select?



 <?php
$username="no
$password="nonono"




$conn = new PDO('mysql:host=localhost;dbname='comments', $username, $password);


?>