use of alias

Hello Everybody,<br /><br />I am trying to change a oracle function to postgreSQL. I have to use the function parameter
indifferent query so i need to use alias command.<br />but i am not able to use this alias in "from  clause" of select
statment.could anybody please let me know how can i use it in from clause.i am getting following error while executing
thefunciton..<br /><br />MT ALIAS FOR  $1;<br />ST ALIAS FOR  $2;<br /><br />select  count(*) into count1 from MT,ST
whereMT.phonenumber=ST.phonenumber;<br /><br /><b>ERROR:  syntax error at or near "$1"<br />LINE 1: select count(*)
from $1 , $2  where MT.phonenumber=ST.phone...<br /><br />Thanx in Advance for all of your suggestion....</b><br /><br
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