Function to return a multiple colmn table or view

<p align="LEFT"><span lang="en-ca"><font face="Arial" size="2">I</font></span><span lang="en-ca"></span><span
lang="en-ca"><fontface="Arial" size="2"></font></span><span lang="en-ca"></span><span lang="en-ca"> <font face="Arial"
size="2">amnew to psql</font></span><span lang="en-ca"></span><span lang="en-ca"> <font face="Arial" size="2">, so
pleasebe patient !</font></span><p align="LEFT"><span lang="en-ca"><font face="Arial" size="2">Can someone please
providea small quick example of a a</font></span><span lang="en-ca"></span><span lang="en-ca"><font face="Arial"
size="2"></font></span><spanlang="en-ca"></span><span lang="en-ca"> <font face="Arial" size="2">function that take 1
paramaterand based on that parameter, returns a table or view ?</font></span><span lang="en-ca"></span><span
lang="en-ca"></span><palign="LEFT"><span lang="en-ca"><font face="Arial" size="2">Etc</font></span><span
lang="en-ca"></span><spanlang="en-ca"> <font face="Arial" size="2">…</font></span><span lang="en-ca"></span><span
lang="en-ca"><fontface="Arial" size="2">.</font></span><span lang="en-ca"></span><span lang="en-ca"> <font face="Arial"
size="2">Note this is just a abstract of the functon, not a working function call !!!</font></span><p
align="LEFT"><spanlang="en-ca"><font face="Arial" size="2">Create function viewtest( start_month) </font></span><p
align="LEFT"><spanlang="en-ca">        <font face="Arial" size="2">If</font></span><span lang="en-ca"></span><span
lang="en-ca"><font face="Arial" size="2">$1 =</font></span><span lang="en-ca"></span><span lang="en-ca"> <font
face="Arial"size="2">‘</font></span><span lang="en-ca"></span><span lang="en-ca"><font face="Arial"
size="2">April</font></span><spanlang="en-ca"></span><span lang="en-ca"><font face="Arial"
size="2">’</font></span><spanlang="en-ca"></span><span lang="en-ca"></span><p align="LEFT"><span lang="en-ca">       
<fontface="Arial" size="2">Then </font></span><p align="LEFT"><span lang="en-ca">        <font face="Arial"
size="2">Select* from april_view;</font></span><p align="LEFT"><span lang="en-ca">        <font face="Arial"
size="2">Return;</font></span><p align="LEFT"><span lang="en-ca"><font face="Arial" size="2">Let me know  how to do
this.</font></span><palign="LEFT"><span lang="en-ca"><font face="Arial" size="2">Thanks</font></span><span
lang="en-ca"></span><spanlang="en-ca"></span>