                        WELCOME TO BORLAND SQL LINK
                          CONNECTING TO INTERBASE
                        ---------------------------

This file contains important, late-breaking information about Borland SQL
Link, including revisions to the documentation.  Information in this file
supersedes information in the SQL Link documentation.


TABLE OF CONTENTS
-----------------

1.  Tips for using SQL Link
2.  SQL Link Documentation Notes
3.  ObjectPAL Tips for SQL Link Applications


1.  TIPS FOR USING SQL LINK
---------------------------

CONNECTING VIA FTP PC/TCP.  Because the FTP PC/TCP connection to InterBase 
requires a large amount of system resources, you may not be able to run 
other Windows applications (such as Help) after connecting to InterBase.  
If this happens, you can reserve system resources by starting a small 
Windows application (like Notepad) before starting Paradox.  After con-
necting to InterBase, you can close the first application.  This reserves
system resources for Help and other Windows applications.

The connection to Interbase via FTP PC/TCP is sensitive to the amount of 
conventional memory available to DOS before Windows is started.  You need 
at least 440 KB to use this connection protocol.


CONNECTING VIA PC NFS.  If you encounter problems using this connection 
protocol, please contact Technical Support for assistance.


IMPROVING PERFORMANCE OF ONE-TO-MANY LINKS.  Often a one-to-many link 
joins a single-field index in the master table to the first field of a 
multi-field index in the detail.  A common example is ORDERS.ORDERNUM 
joined to LINEITEM.ORDERNUM, where LINEITEM  has a unique index on its 
ORDERNUM and ITEMNUM fields together.  In InterBase 3.3 you can sometimes
improve performance by adding a non-unique index on LINEITEM.ORDERNUM 
alone.


USING ALIASES WITHOUT SPECIFYING A LANGUAGE DRIVER.  If no language
driver is specified, the default language driver is ASCII.  Language-
specific processes like character translation and table name validation 
will default to U.S. rules.  For further information, see the section
on Borland language drivers in your Connecting To... manual.


  
WORKING WITH LARGE TABLES.  If you create data entry forms on large tables
you may find some performance degradation -- particularly if the user is 
allowed to view unrestricted record sets.  The following suggestions may 
help cut down the load on your server and help optimize server perfor-
mance:

-  With large data sets, it is good programming practice to write 
   applications which access relatively few records at a time.  One way to
   do this within a form-based application is to create forms which order
   the data by index and set RANGE criteria to limit the record set.  
   This can be done interactively using the ORDER/RANGE dialog, but can 
   also be controlled by the application developer.  (For example, instead
   of creating a form which displays all orders for all customers, write
   your application to limit the user's working selection by criteria such
   as customer name, state, and area code.)

-  Forms which update existing data must be indexed in InterBase.  At 
   least one unique index is required.

-  Where possible, create applications which order on fields which were
   created with the REQUIRED (NOT NULL) option.  Since this field
   property must be specified at the time of table creation; be sure to 
   plan for this as part of your application design.

-  To significantly improve performance, create both ascending and 
   descending indexes on fields which are frequently used to order data
   in forms.



2. SQL LINK DOCUMENTATION NOTES
-------------------------------


INTERBASE BLOB SUBTYPE SUPPORT.  SQL Link supports the creation of text-
type blobs in InterBase.


SQL LINK USER'S GUIDE, PAGE 13.  Two additional points for the subsection
on "Using Table windows" are: (1) The .TVS file is not automatically 
deleted when the SQL table is deleted, and (2) If you change your private 
directory the table will no longer be displayed with the properties you 
set.


SQL LINK USER'S GUIDE, PAGE 14.  Add the following note before the para-
graph that begins with "For detailed information..."

     NOTE:  The above tables are only generated if the query is processed
            within the QBE environment.  For further information, see
            "QBE query processing," in Chapter 3.


SQL LINK USER'S GUIDE CHAPTER 4.  Chapter 4, "SQL-enabled ObjectPAL," does
not document the transactionsActive() database method or the 
update(fname,fvalue [,fname,fvalue]) tcursor method.  For information
about these two methods, see NEWPAL.DB. 


SQL LINK USER'S GUIDE, PAGE 29.  The description of the syntax for 
beginTransaction includes the parameter ([const isoLevel String]).  This
parameter is not supported in this release of SQL Link.


SQL LINK USER's GUIDE, PAGES 29 - 31.  Tables 4.5 and 4.6 are not sorted
by object type.

SQL LINK USER'S GUIDE, PAGE 30.  Table 4.5, "Standard ObjectPAL methods
that support SQL Link," includes the sort table method.  The sort method
belongs in Table 4.6, "Standard ObjectPAL methods that do not support
SQL Link." 


SQL LINK USER'S GUIDE, PAGE 37.  peOptRecLockFail should be
peOptRecLockFailed. Error constant is incorrect.


SQL LINK USER'S GUIDE, PAGE 40.  The steps for rebinding forms discussed
on this page of the User's Guide should be corrected as follows:

1.  Copy Paradox tables to the SQL server.

2.  Index the server tables to duplicate the linking and ordering indexes
    you had on your original tables.

3.  Before you rebind the form, copy it to a different subdirectory so that
    Paradox for Windows will not be able to find the original tables when
    you open the form.

4.  Change your working directory to the new subdirectory and Open the form
    in Design Mode.

5.  When the original Paradox tables cannot be found, you will be allowed 
    to replace those tables in the data model with the equivalent SQL 
    tables.

6.  In some cases, you may need to fix up the links between tables in the
    Data Model dialog.  To do this, simply unlink all tables and re-link
    on the appropriate indexes.

7.  Recreate all calculated fields.

8.  Update all hard-coded table names in ObjectPAL code.

9.  Save the form.


3. OBJECTPAL TIPS FOR SQL LINK APPLICATIONS
-------------------------------------------

For tips on how to create ObjectPAL applications for use in an SQL 
environment, see the text file OPALTIPS.TXT.