Help with attempting to add time to a MySQL field from PHP?

[bobmct]

In my feeble attempt to keep track of login session timeouts I have the
following code in my login section of my program:

$sql = "UPDATE subscriber
SET _sessexp = 'DATE_ADD(NOW() ,INTERVAL 15 MINUTES)'
WHERE _userid = '$_userid'
LIMIT 1";

and when run I see NO ERRORS. However, either the field in the DB doesn't
change OR this expression is generating a value of '0' for the _sessexp
field.

I've tried using the ADDTIME function as an alternative but get the same
results. I'm kind of at a loss.

Any ideas as to why this is NOT behaving as I expect it to?

What I am attempting to do is to take the CURRENT TIME and add 15 minutes to
it and update a field in the database record. That simple!

Bob

[Rik]

Re: Help with attempting to add time to a MySQL field from PHP?

bobmct wrote:

In my feeble attempt to keep track of login session timeouts I have
the following code in my login section of my program:
>
$sql = "UPDATE subscriber
SET _sessexp = 'DATE_ADD(NOW() ,INTERVAL 15 MINUTES)'
WHERE _userid = '$_userid'
LIMIT 1";
>
and when run I see NO ERRORS. However, either the field in the DB
doesn't change OR this expression is generating a value of '0' for
the _sessexp field.
>
I've tried using the ADDTIME function as an alternative but get the
same results. I'm kind of at a loss.
>
Any ideas as to why this is NOT behaving as I expect it to?
>
What I am attempting to do is to take the CURRENT TIME and add 15
minutes to it and update a field in the database record. That simple!

First of all, you try to add the string 'DATE_ADD(NOW() ,INTERVAL 15
MINUTES)' to a date field, which is invalid and will result to 0. Remove the
quotes.
Grtz,
--
Rik Wasmus

[bobmct]

Re: Help with attempting to add time to a MySQL field from PHP?

Rik wrote:

bobmct wrote:

>In my feeble attempt to keep track of login session timeouts I have
>the following code in my login section of my program:
>>
> $sql = "UPDATE subscriber
> SET _sessexp = 'DATE_ADD(NOW() ,INTERVAL 15 MINUTES)'
> WHERE _userid = '$_userid'
> LIMIT 1";
>>
>and when run I see NO ERRORS. However, either the field in the DB
>doesn't change OR this expression is generating a value of '0' for
>the _sessexp field.
>>
>I've tried using the ADDTIME function as an alternative but get the
>same results. I'm kind of at a loss.
>>
>Any ideas as to why this is NOT behaving as I expect it to?
>>
>What I am attempting to do is to take the CURRENT TIME and add 15
>minutes to it and update a field in the database record. That simple!

>
First of all, you try to add the string 'DATE_ADD(NOW() ,INTERVAL 15
MINUTES)' to a date field, which is invalid and will result to 0. Remove
the quotes.
Grtz,

Well, OK;

Already tried that first. With/without, single/double, doesn't seem to
matter.

Re-tried your suggestion and the result STILL results in ONLY ZERO in the
field. However, can a time function's result be put into a bigint field?

Bob

[Rik]

Re: Help with attempting to add time to a MySQL field from PHP?

bobmct wrote:

Rik wrote:
>

>bobmct wrote:

>>In my feeble attempt to keep track of login session timeouts I have
>>the following code in my login section of my program:
>>>
>> $sql = "UPDATE subscriber
>> SET _sessexp = 'DATE_ADD(NOW() ,INTERVAL 15 MINUTES)'
>> WHERE _userid = '$_userid'
>> LIMIT 1";
>>>
>>and when run I see NO ERRORS. However, either the field in the DB
>>doesn't change OR this expression is generating a value of '0' for
>>the _sessexp field.
>>>
>>I've tried using the ADDTIME function as an alternative but get the
>>same results. I'm kind of at a loss.
>>>
>>Any ideas as to why this is NOT behaving as I expect it to?
>>>
>>What I am attempting to do is to take the CURRENT TIME and add 15
>>minutes to it and update a field in the database record. That
>>simple!

>>
>First of all, you try to add the string 'DATE_ADD(NOW() ,INTERVAL 15
>MINUTES)' to a date field, which is invalid and will result to 0.
>Remove the quotes.
>Grtz,

>
>
Well, OK;
>
Already tried that first. With/without, single/double, doesn't seem
to matter.
Re-tried your suggestion and the result STILL results in ONLY ZERO in
the field.

DATE_ADD(NOW(), INTERVAL 15 MINUTE)

NO 's' after MINUTE

However, can a time function's result be put into a
bigint field?

I'm not sure what database you use, but in recent MySQL versions it will
return a format of yyyy-mm-dd hh:mm:ss, not an integer.

Do you by any chance mean UNIX_TIMESTAMP( DATE_ADD(NOW(), INTERVAL 15
MINUTE))?

Grtz,
--
Rik Wasmus