SQL Query and Variable help

[redgunner]

:shrug:

 

	$id = '9';

$MyQuery = "SELECT * FROM bookings WHERE id = '$id'";
$retrieve = mysql_query($MyQuery) or die(mysql_error());
if(mysql_num_rows($retrieve) != 0):
	$row = mysql_fetch_assoc($retrieve);
else:
	echo 'No Information';
endif;	

echo 'Full Name: ' . ($row['fullname']) . '<br><br>';	

 

The above code is working for me however when I change it to what I do...

 

	$id = ($row['id']);

 

It tells me I have an undefined row variable... What will fix this? Thanks in advance...

[Vince889]

Because the $row variable is being created within a conditional statement, it will only be created IF that statement is true.

In the case, the $row variable will only be set IF  the numbers of rows DOES NOT equal zero. Obviously, the query is returning 0 and not setting your $row variable. <-- Ignore that, I misread.

 

Its because you're referencing the $row variable before the $row variable even exists. The $row variable isn't defined until here:

$row = mysql_fetch_assoc($retrieve);

 

After that, assuming that the conditional statement succeeds, you can use it. Otherwise, if a variable has not been set/defined/exists prior to use, PHP will return an error.

[redgunner]

Yeah but everytime I go to define the $row variable I still need to pickup on $id and is really confusing me...

 

Could I be so bold to ask what a working code would be?

[Pikachu2000]

You can't use the variable before it's defined, therefore you can't use it as part of the WHERE clause in that query before the query has even run. Please explain exactly what you're trying to do with this code.

[redgunner]

The page is edit.php?id=x

x being unique primary key

 

I just need $id variable to set it to whatever that number is...

[Pikachu2000]

Oh, that's easy enough . . .

 

$id = (int) $_GET['id']; // typecast to integer when the incoming value is expected to be an integer . . .

[redgunner]

Tried that and I get this...

 

Notice: Undefined index: id in C:\Users\Chris\Desktop\www\edit.php on line 9

No Information

Notice: Undefined variable: row in C:\Users\Chris\Desktop\www\edit.php on line 19

ID:

 

the previous page has

<a href="edit.php?id.php='.$row['id'].'">edit</a>

 

Im totally stuck on this1 and ive tried everything

[Pikachu2000]

Would you explain exactly what it is you're trying to do, and in what order things are currently being done? That would make it a lot easier to help you with this.