• Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 2942
  • Last Modified:

PHP MySQL Not Equal Comparison between Two Tables

I have two tables.  MySQL version 4.1.22-standard -  PHP 5.2.4.  

I'm trying to get the data from the Review Table that do not have entries in the Comment Table.  

Here's what I have..

First Table   Review - Fields ->  (item_id / date / user_id)  

Second Table Comments - Fields -> (comm_id, item_id, user_id,date)

Code Below.. Thanks..
SELECT Review.item_id, Review.date, Review.user_id, Comments.item_id
FROM Review, Comments
WHERE Review.item_id <> Comments.item_id

Open in new window

0
usiff
Asked:
usiff
  • 4
  • 2
1 Solution
 
hernst42Commented:
You can try the SQL below
SELECT Review.item_id, Review.date, Review.user_id
FROM Review LEFT OUTER JOIN Comments on (Review.item_id = Comments.item_id)
WHERE Comments.item_id IS NULL

Open in new window

0
 
dansotoCommented:

SELECT Review.item_id, Review.date, Review.user_id, Comments.item_id
FROM Review
WHERE Review.item_id NOT IN 
(SELECT Comments.item_id from Comments); 

Open in new window

0
 
usiffAuthor Commented:
Hello hernst42:

Here is another quick issue..

When I add this code below is doesn't work...
WHERE Comments.item_id IS NULL AND Review.user_id = $_SESSION['user_login_id']

But this will work?
WHERE Comments.item_id IS NULL AND Review.user_id = '444'

What the heck I'm I missing?

Thanks

usiff
0
Free Tool: Subnet Calculator

The subnet calculator helps you design networks by taking an IP address and network mask and returning information such as network, broadcast address, and host range.

One of a set of tools we're offering as a way of saying thank you for being a part of the community.

 
hernst42Commented:
maybe $_SESSION['user_login_id'] is empty and does not contain anything. What do ypu get when you print out var_dump($_SESSION['user_login_id']) before you create the SQL?
0
 
usiffAuthor Commented:
Hello hernst42,

It's printing our string(1) "444"

It's crazy..
0
 
usiffAuthor Commented:
It's working now..  Wow...  I was going crazy!!  

I love typosss

Thanks again!

0
 
usiffAuthor Commented:
Thanks!
0

Featured Post

Free Tool: ZipGrep

ZipGrep is a utility that can list and search zip (.war, .ear, .jar, etc) archives for text patterns, without the need to extract the archive's contents.

One of a set of tools we're offering as a way to say thank you for being a part of the community.

  • 4
  • 2
Tackle projects and never again get stuck behind a technical roadblock.
Join Now