which is better single query or multiple query?

mathew

I do have 8 tables. when a query fires from search page data from all these 8 tables is pulled out and displayed on the result page. What I want to know is which is the best optimized query method for this process??

what I do now is :

$result = mysql_query("SELECT * FROM TG_dat,TG_dat1,TG_dat2,TG_dat3 WHERE 
TG_dat.web = TG_dat1.web AND TG_dat.web = TG_dat2.web AND TG_dat.web = 
TG_dat3.web AND TG_dat.web='".$uri."'")or die(mysql_error());

or do i need to use this??

$result = mysql_query("SELECT * FROM TG_dat WHERE web='$uri'")or die(mysql_error());
$result = mysql_query("SELECT * FROM TG_dat1 WHERE web='$uri'")or die(mysql_error());
$result = mysql_query("SELECT * FROM TG_dat2 WHERE web='$uri'")or die(mysql_error());
$result = mysql_query("SELECT * FROM TG_dat3 WHERE web='$uri'")or die(mysql_error());