how to check numeric value of field in database in asp using javascript and update

[dosa]

hello
the promblem is when i want decrement the value of field in database didn't work like this:

copy=rs.fields( "num_copies").v alue;
copy=copy-1;


then i want update the value of field (num_copies) in database

<%@language="javascript"%>
 <!--#include file="connection.asp"-->
  <%

 
   RS.open("SELECT *FROM book_info where (num ="+Request.form("No_Book")+")and(title_book='"+Request.form("Book1")+"')",abCon);
	if(!RS.EOF)
      {
	   
	    if( RS.fields("num_copies").value >1)
	      {
		  copy=RS.fields("num_copies").value;
	       rent=RS.fields("Rent_book").value;
	       copy=copy-1;
		   rent=rent+1;
		   RS.Fields("num_copies")=copy;
		   RS.Fields("Rent_book")=rent;
	       RS.Update;
          RS.Close;
         abCon.close;
		
	      }
     else
	  {
	    Response.write("There is no enogh copies of this book");
	  
	   RS.close;
	   abCon.close;
	   }
	   }
   %>

[Rabbit]

You haven't explained what problem you're having with your code.

[dosa]

hello i want know how to do it my code is wrong

[VanessaMeacham]

Hi Give the Clear Description that which kind of Problem you face with this code.

[Rabbit]

Your Copy variable is only a copy of the data on the database. It is not linked to the value in the database itself.

You will need to run an update query.

[sharmajv]

Have u tried using

copy=rs.fields("num_copies").value;
copy=CInt(copy)-1;