Q131265: Use Exclamation Mark (!) Notation for Precise Referencing

Article: Q131265
Product(s): Microsoft FoxPro
Version(s): WINDOWS:3.0
Operating System(s): 
Keyword(s): 
Last Modified: 15-FEB-2000

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, version 3.0 
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SUMMARY
=======

Use the exclamation mark (!) notation to reference tables in databases (.DBC
files). Use it to reference tables that have the same names but that exist in
different databases, and use it to make code more readable. Its main purpose is
to guarantee the opening of a specific table.

MORE INFORMATION
================

Here is the syntax:

     USE <cDatabase_name>!<cTable_name>

NOTE: Do not put spaces on either side of the exclamation mark.

Step-by-Step Example
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1. Create the following directory structure:

  C:\MAIN
  C:\MAIN\ONE
  C:\MAIN\TWO

  This can be done Visual FoxPro by issuing these commands:

  CD C:\ 
  MD MAIN
  CD C:\MAIN
  MD ONE
  MD TWO

2. Issue the following commands in the Command Window:

     CD C:\MAIN\ONE
     CREATE TABLE tb_mytbl (fld1 c(10))
     CD C:\MAIN\TWO
     CREATE TABLE tb_mytbl (fld1 c(10))
     USE
     CD C:\MAIN
     CREATE DATABASE db_one
     ADD TABLE C:\MAIN\ONE\tb_mytbl
     CREATE DATABASE db_two
     ADD TABLE C:\MAIN\ONE\tb_mytbl
     SET DATABASE TO db_one

  These commands set up a scenario where a database named db_one contains a
  table named tb_mytbl, which is located in the C:\MAIN\ONE directory. Another
  database named db_two contains a different table named tb_mytbl, which is
  located in the C:\MAIN\TWO directory.

  The issue is to open the tb_mytbl table in the db_two database. The current
  database is db_one, so you can't use this command:

        USE tb_mytbl

  It would open the table in db_one located in C:\MAIN\ONE.

3. Open the tb_mytbl table in the db_two database by using this command:

     USE db_two!tb_mytbl

The exclamation mark (!) notation works in the same manner for long table names,
and it makes code more readable. The notation makes it clear exactly which
database holds the table of interest. It is especially useful in SQL-SELECT
statements.

Additional query words: VFoxWin !-symbol bang symbol

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Keywords          :  
Technology        : kbVFPsearch kbAudDeveloper kbVFP300
Version           : WINDOWS:3.0

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