'if' conditionals acting reverse

BEFOR

The below if statements occur within a repeat region.
Why are if's acting in reverse?
The query is correct, as a sperate echo has verified.
Duplicating the query within this column makes no difference.
Is this because the 'if' is on the LEFT OUTER JOIN value?

MPID comes from a LEFT OUTER JOIN
MPID is the primary id

if($row_All['MPID']<>NULL) //does not result in an echo (but should) when a record does exist

if($row_All['MPID']==NULL)//does result in an echo when a value exists (but shouldn't)

if(!empty($row_All['MPID']))//does not result in an echo (but should) when a record does exist

if(empty($row_All['MPID'])!='')//does result in an echo when a value exists (but shouldn't)
###########################

SELECT *
FROM Members, Submits, MNotify LEFT OUTER JOIN MemPay as mp on
(mp.MPMem_ID=Members.MemID and Members.MemID=colname and mp.MPSub_ID=MNotify.FK_SubmID)
WHERE Submits.SubmID=MNotify.FK_SubmID and Members.MemID=colname

MemPay - payment table, where
MPID | MPMem_ID (actually foreign) | MPSub_ID

Members
MemID

Submits - submitted ads
SubID

MNotify - Members become notified of individual submitted ads
MNID | FK_MemID | FK_SubmID

this occurs in a repeat region where Members can view each MNotify.FK_SubmID (submitted ads, ea. of which can have a different status -- hence the conditions -- the ads may be bought, and if so, they are found in MemPay table. MPMem_ID is the buyer and MPSub_ID is the submitted ad they bought.)

bogu

BEFOR wrote:
if(empty($row_All['MPID'])!='')//does result in an echo when a value exists (but shouldn't)

this is not correct empty() function is a boolean function witch return true or false, why do u compare true or false with empty value?

BEFOR wrote:
if($row_All['MPID']<>NULL) //does not result in an echo (but should) when a record does exist

this could be write this way too ...

if (!is_null($row_All['MPID']))

is_null also a boolean function ...

BEFOR wrote:
Is this because the 'if' is on the LEFT OUTER JOIN value?

If statement don't care where do u take your value from it cares if your value is true or false, if statement is working like this:

/* will echo always True */
if (true) echo "True";
else  echo "False";
/*
 *OR 
 *will echo always False 
 */ 
if (false) echo "True";
else  echo "False";

Installer

will echo always False
/
if (false) echo "False";
else echo "True";

No, that code will always echo "True", since boolean false is equal to boolean false.

BEFOR

then what can be used for
$row_All['MPID']

as a condition to check for a resulting echo when:

a) there is no record
b) there is a record

Is there an issue with checking on a LEFT OUTER JOIN value?

bogu

Installer wrote:
No, that code will always echo "True", since boolean false is equal to boolean false.

Ups ... :p
your right ... 😃
I reedit my post, I was in a hurry ...

bogu

BEFOR wrote:
then what can be used for
$row_All['MPID']

as a condition to check for a resulting echo when:

a) there is no record
b) there is a record

Is there an issue with checking on a LEFT OUTER JOIN value?

echo your $row_All['MPID'], the value could be: ex. either null (is_null()) or either empty (empty()) if none of those it means you got a value ...

Installer

🙂

BEFOR

How could it be possible that when:

<?php
if($row_All['MPID']<>NULL){echo'record exists';}?> //nothing echoes

at the same time:

<?php echo $row_ALL['MPID']; ?>

echoes the value on the page?

now the ALL query is only query of its type on the page, no repeat regions, with this being the only test.

did try also:

if (!is_null($row_All['MPID']))

which causes the page to only partially load.