I'm guessing you're asking about parameter substitution when using dynamic SQL which is ran within a cursor? I think it would depend upon the database product that you are using?
Informix had a nice feature allowing you to bind form variables to SQL cursors;
Constuct Bt Name - Informix 4GL
In Sybase and Powerbuilder I recall their where four main types of dynamix cursors;
Dynamix SQL - I'm guessing that this still applies to SQL Server since Mirco$wipe "based" their product on Sybase AS.
I recall some horrific outsourced code I had the misfortune of modifying, a lot of nasty code that defined a type 4
SQLDA dynamic cursor. Using SQLDA you are allowed to define a cursor in which the input parameters and types and the the result set and types are not defined until the querry runs. Just because you can, does not mean
you should however.