Hello friends I am new to wordpress.
I have used query like this query_posts('cat=1,2,3')
now If category 1 is parent of 2 and 3.
then query_posts('cat=1') and query_posts('cat=1,2,3') will get same posts or not? or how can I manage If I want to include posts form subcategories.
In short: Yes.
Your question is about the query_posts Wordpress PHP function. The link I've placed is the official wordpress codex documentation for that function.
For your example it states:
Display posts from only one category ID (and any children of that category):
query_posts('cat=4');
I hope this information is helpful. You find more infos in codex, the function is pretty powerful.
Yes, cat=x get's posts in x and all sub-categories, if you don't want this behavior doing category__in => array( x ) will only get posts specifically in that category.
I can't comment yet, so I have to submit an answer. To map Joe Hoyle's answer on to query_posts, you'd do the following:
query_posts('category__in=1');
That'd would give you just the main category, without the subcategories.
It's not what the OP was asking for, but I found this via Google when searching for how to just show the main category, so others may find this too.
