[RESOLVED] Return NULL

zzz

I have a few fields in db tables that are set to NULL, however if I post a form and that updates that table it'll change the NULL to whatever value corresponds.

Now, I need to be able to change it back to NULL if a user updates the form and clears the form field or puts a space in it.

What's the best way to do it?

etully

update customers set name=null where id=75;

zzz

I think my problem is that currently I have something like this:

$value = trim(addslashes($_POST['myvalue']));

update customers set name="' . $value . '" where id=75;

If they put a space trim will take care of it and then I can do something like:

if (empty($value)) {
   $value = null;
}

But then my query will be update customers set name= "null" ... and my db will think this is an entry and not NULL.

NogDog

Perhaps something like this?

$value = trim($value);
$value = ($value === '') ? "null" : "'".mysql_real_escape_string($value)."'";
$query = "update customers set name=$value where id=75";

zzz

I was leaning this way but thought I was overcomplicating this. I'll give it a shot.

Question:
what does tripple === mean?

Also I've see people using : and ? to conjoin the parts of a string but can never find how to use it properly... What is it?

zzz

Ok found ===

TRUE if $a is equal to $b, and they are of the same type. (introduced in PHP 4)

Shouldn't I also change

$value = ($value === '') ? "null" : "'".mysql_real_escape_string($value)."'";

$value = (empty($value)) ? "null" : "'".mysql_real_escape_string($value)."'";

zzz

Here's final working code:

$value = trim(addslashes($value)); 
$value = ($value === '') ? "null" : "'".$value."'"; 
$query = "update customers set name=$value where id=75";

For some reason mysql_real_escape_string doesn’t work is the input is like O'Connor, i.e. has an apostrophe