how to include if condition with like under select query

[reddymade]

How to include an if condition to see wether $areacode is null or not, under the select query before executing:

areacode like '%".$areacode."%'

$strSQL = "Select distinct id, login, SUBSTRING(comment,1, 165) as comment, gender, date_birthday,icon_path, default_icon as icon_path_default,
from ".USERS_TABLE."
where date_birthday like '%-".date("m")."-".date("d")."%'
and status='1' and root_user = '0' and guest_user='0' and id != '".$user[0]."' order by id".$limit_str;

Thank you very much for the information.

[The_Chancer]

$query="Select distinct(id), login, SUBSTRING(comment,1, 165) as comment, gender, date_birthday,icon_path, default_icon as icon_path_default  from ".USERS_TABLE."
where date_birthday like '%".date("m")."-".date("d")."%'
and status='1' and root_user = '0' and guest_user='0' and id != '".$user[0]."' AND areacode!=null order by id".$limit_str";

SHould sort you

[reddymade]

Hello Chancer,

I need a like query for areacode.

if the user want to make a search with a specific areacode, otherwise i don't want to include the like in the select query where condition.