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Q128890: How the Import Wizard Determines the Text File Type

Article: Q128890
Product(s): Microsoft FoxPro
Version(s): WINDOWS:3.0
Operating System(s): 
Keyword(s): 
Last Modified: 12-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
=======

The Import Wizard assists you in creating a FoxPro table from another type of
file, such as a text file. This article explains how FoxPro determines the type
(fixed-length, comma-delimited, or tab-delimited) of text file you are
importing.

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

Determining Records to Analyze
------------------------------

When you import a text file using the Import Wizard, by default it reads the
first 50 records in the text file. To begin analysis at a different row, or
perform analysis on all records, choose the Options button in the "Step 1a -
Options" screen of the Import Wizard.

NOTE: The analysis of records cannot be manually interrupted.

Determining File Type
---------------------

The following tests are performed in the order listed to determine the file's
type:

1. Do all records have the same length? If true, this is a fixed-length file.

2. Do all records have the same number of commas? If true, this is a
  comma-delimited file.

3. Do all records have the same number of tabs? If true, this is a tab-delimited
  file.

4. Do all records have the same number of semicolons? If true, this is a
  semicolon-delimited file.

5. If none of the previous tests are true, the Import Wizard assumes the file to
  be a fixed-length file, using the length of the longest record in the
  50-record sample as the record length.

Determining File Structure
--------------------------

Once the file's type is determined, the following tests are performed to
determine its structure.

- Fixed-length Files: Each record is analyzed to determine potential column
  breaks, by tracking the locations in each record where a space is followed by
  a non-space character. When 75% or more of the records have this transition
  from a space to non-space character in the same location, that location is
  assumed to be a column break. This is how the Import Wizard decides where to
  place the default column breaks displayed in Step 1a.

- Delimited Files: Each field in all records is analyzed to determine the
  maximum field lengths. All fields are assumed to be character unless a field
  is wider than the maximum character field width, in which case the field is
  assumed to be a memo field.

Additional query words: VFoxWin semi-colon 3.00

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

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