gdreadme.txt

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This is the "readme" file for the GenDBCX utility.


Introduction
------------

A replacement for Microsoft's GenDBC utility, GenDBCX creates
a program that defines a class that contains a separate
method to recreate each table, view, connection, relation
and referential integrity constraint contained in a
database container (.dbc).

The major enhancements of GenDBCX over GenDBC are:

1) No more 'Program too large' errors, since the recreation program
consists of separate procedures for each table, view, etc., as
opposed to GenDBC's monolithic structure;

2) The required available disk space is minimized, as we write
directly to the output regeneration file, and avoid the use of
memo fields, which can bloat excessively and quickly when you
frequently add new strings to their contents;

3) Execution speed is on the order of two to three times faster,
mostly due to not using memo fields;

4) Since the output program defines a class, and each recreation
routine is a method of that class, you can incorporate GenDBCX's
output into an application, and call its methods to recreate
individual tables in the database.

5) GenDBCX provides a "hook" between the code that creates each
table, and the code that creates the table's properties.
Into this hook, you can insert any code that you need, such
as appending data from an existing table.


Installation
------------

As a simple utility, there's really nothing to install.
Simply copy the program file to wherever you want to run it
from, and have at it!


Usage
-----

You call GenDBCX the same way you call GenDBC, i.e.
DO GenDBCX [with "<OutputFileName>"].  You have an
additional argument, ["<ClassName>"], which represents
the name of the class you want GenDBCX to create.  The
full syntax of the program call is now:

 DO GenDBCX [with "<OutputFileName>"[, "<ClassName>"]]


Notes
-----

In most cases, GenDBCX "straight out of the box" will work
just fine for you.  If your database container (.dbc)
file gets "hosed", just run the program to recreate the
.dbc, copy the .dbc, .dct and .dcx files to your data
directory, and you're done!

In some situations, however, this simple recreation of the
database container may not suffice.  For those of you who
require additional processing of your database tables, we
have added the "CustomProcess" hook.  "CustomProcess" is
a method that is defined at the beginning of the GenDBCX
class; it is called after all the tables in your database
have been recreated, but before the database rules,
relations and triggers are re-instantiated.

The CustomProcess method allows you to add any code that
your database requires before its rules, relations and
triggers are re-instantiated.  For example, if you are
using GenDBCX to create a VFP database from a FoxPro 2.x
database on a regular (or not-so-regular) basis, you can
use the CustomProcess hook to append the data from your
2.x tables to your VFP tables before you add your VFP
constraints.

In order to use the CustomProcess hook, you must do the following:

1) Create a file called CustProc.h, and place it in a directory
   where the database recreation file can find it;

2) Within CustProc.h, #DEFINE a named constant called
   CUSTOM_METHOD_LOC, and assign to it the code that you
   want GenDBCX to #INCLUDE into the database recreation
   program.  For example:

	#DEFINE CRLF chr(13) + chr(10)
	#DEFINE TAB  chr(9)

	#DEFINE CUSTOM_METHOD_LOC ;
		TAB + TAB + "LOCAL laTables[1], pcOutputDirectory, i, lnOldArea" + CRLF + ;
		TAB + TAB + "CLOSE TABLES ALL"
		TAB + TAB + "lnOldArea = SELECT()" + CRLF + ;
		TAB + TAB + "SELECT 0" + CRLF + ;
		TAB + TAB + "pcOutputDirectory = 'D:\VFP5WORK\CONVERT\OUTPUT\'" + CRLF + ;
		TAB + TAB + "ADBOBJECTS(laTables,'TABLE')" + CRLF + ;
		TAB + TAB + "FOR i=1 TO ALEN(laTables)" + CRLF + ;
		TAB + TAB + "	IF FILE(pcOutputDirectory + laTables[i] + '.DBF')" + CRLF + ;
		TAB + TAB + "		USE (laTables[i])" + CRLF + ;
		TAB + TAB + "		APPEND FROM (pcOutputDirectory + laTables[i])" + CRLF + ;
		TAB + TAB + "	ENDIF" + CRLF + ;
		TAB + TAB + "NEXT i" + CRLF + ;
		TAB + TAB + "USE" + CRLF + ;
		TAB + TAB + "SELECT (lnOldArea)" + CRLF

Remember, CustomProcess is a separate method; you can do
anything you need to do within it to properly recreate
your database container and tables.


Updates & Problem Notification
------------------------------

To receive updates to this program as they become available,
please send a note containing your name, company name, and
email address to:

			[e-mail]

Please also use this email address to notify us of any
problems you encounter using GenDBCX, as well as letting
us know of any enhancements that would make the program
more valuable to you.


Steve Arnott
[e-mail]
CIS 70247,2614