Language Guide

Altering SQL Tables

SQL users know they can ADD or DROP fields from an SQL TABLE by using the ALTER TABLE command. Similarly, entire files can be added to (or dropped from) an SQL DATABASE with the ALTER DATABASE command.

heitml wouldn't be complete if it didn't give you the same degree of control over your environment, so we'll show you how to do that with the <dbupdate> Tag. Although we won't spend a lot of time here, the syntax of <dbupdate> is quite simple, and you shouldn't have any trouble applying it in a wide variety of situations.

To ADD a field:	To Drop a field:
<dbupdate> ALTER TABLE guestbook ADD Password CHAR(8) </dbupdate>	<dbupdate> ALTER TABLE guestbook DROP Password <dbupdate>

Naturally, it is beyond the scope of this Language Guide to enter into a discussion of the relative merits or potential pitfalls of allowing Client Users to make modifications to your SQL TABLES and DATABASES. There may be times, however, when you, the application designer, find it convenient to make such modifications on your own Server while working within the heitml framework. In any case, heitml's goal is to provide a seemless, integrated HTML/SQL environment. We can only assume, therefore, that you have taken the precaution of defining a list of valid User Names and Passwords in the Security Database on your Server, thus protecting your SQL DATABASES from unauthorized changes.