'210010106140040100' == '210010106140040101'

Posted on 16th Feb 2014 07:03 pm by admin

Debugging this simple line of a PHP script

Code: if($a == $b){ }
I've found that with value of
$a = '210010106140040100' (type = string)
$b = '210010106140040101' (type = string)

the result of the comparison is TRUE

the same if i compare 2 integer

$a = 210010106140040100 (type = int)
$b = 210010106140040101 (type = int)

$a == $b ( true )

If I use the === operator

'210010106140040100' === '210010106140040101' (comparison of strings: result is FALSE)
210010106140040100 === 210010106140040101 (comparison of numbers: result is TRUE)

I think it could be caused by the fact that the string is 'like' integer, but exceed the standard size of integer number.
But the final result remain a mistery for me: I've tested some others 'big' numbers and I've found for example:

18014398509481980==18014398509481981 (true) !!!!
18014398509481982==18014398509481981 (false) !!!!

In my specific script i can handle this specific comparison using the === operator, because i can assume that the variable are string.

But i'd like to know why this happen, and i'd appreciate suggestions about how to efficiently compare 'big' integers.

Thanks!

I use PHP 5.2 with IIS

Your Answer:

Login to answer

Other forums

Help with echo()
I'm having some problems with this code:

Code: echo '
<A HREF="jav

Date Format
Hi there,

I have a date format like this right now:
Sat, 17 Oct 2009 17:04:00

I ne

FAGL_FC_TRANSLATION FAS52 New GL ECC 6.0
Hello,

The new program for Translating GL Balances (FAS 52) gives the option to use diffe

Auto-populating dropdowns and multiple forms.
Here's what I have so far:

First drop down = select a state (works)
This populates the sec

pls clear my confusion
Hi friends,

Pls solve my query .

what is the exact use of Scope Resolution Operator( i

php not working written for consumption of slots
1. Here is the function where i will be allowed to consume the slot booked by me.

2. Here i c

$_FILES array
Ok,

I just started experimenting with PHP today. My goal right now is to have people be able

help with mysql_error()
Hi,

I am trying to insert data into a table, but I am not able to insert it. I wanted to see

Nested (echoed) php running wrong script
Got a problem with a php website I'm creating.

In a nutshell, the first page is entirely html

MySQL issue
I am taking sentences through a form on page. Then checking some condition and trying to insert them