Reading Paradox Files

Back in the day, Paradox was a pretty amazing database.  I recently had a reason to read some Paradox files for a friend, who had a client with a Paradox database.  They needed their data out of the database to insert into something more modern.

Googling for the file format of a Paradox DB didn’t turn up much, other than this excellent document written in 1996.  It was enough to give me a good start.  I also found some sample DB files, interestingly from the Paradox documentation.

The end result was paradoxReader, which you can download here.  It handles most of the data types other than BLOBs, so far.  The documentation on how to use it is here.  It uses the visitor pattern, which means all you need to do is pass it an InputStream to a .db file, and implement a single interface which is called once per row, with the row data.

The default implementation currently outputs CSV for each table, however it wouldn’t be difficult to have it output SQL or even just connect to a JDBC database and insert the data into a table.

Similar Posts

  • TNT

    If you haven’t read this book, I highly recommend it.  I discovered it in high school and finally purchased my first copy at the now-gone Duthie Books in Kitsilano.  Without going into the details of the book, the author uses a simple Peano arithmetic called Typographical Number Theory  (TNT) to illustrate some of his points. An example…

  • phpGrammar

    I’ve recently becoming interested in porting legacy PHP sites to JSPs.   It seemed to me that one of the hardest parts of this problem was parsing the PHP code.  Once a parse tree was created, the next step would be to emit equivalent JSP code. I went looking for an ANTL4 grammar for PHP,…

  • Parsing HTML

    I’ve been interested in HTML parsing for a while now.  There are a number of reasons to do this, such as: Validating that what claims to be HTML, is HTML Finding every style sheet and script in an HTML file Pretty-printing Syntax highlighting Linting Translating between markup languages, for example generating JSPs from PHP, or…

4 Comments

  1. Hi,

    This is great!
    I recive a Exception:
    Caused by: java.lang.Exception: Unknown field type ‘4’
    at com.khubla.pdxreader.db.DBTableField.readFieldTypeAndSize(DBTableField.java:119)
    … 5 more

    I can see that FieldType 4 is missing. Do you know whay you fiealdType 4 is not implemented?

    BR
    Mats Ahlbom

    1. Hi!

      I also use this great library to read old paradox db files and faced the same problem. But I’ve fixed this with little patch of the lib. Unknown field type ‘4’ is an integer type, there is also type ’21’ missing for timestamp fields.

      I supported two new FieldType enum values and their handling in DBTableValue and that’s worked.

  2. Hi,
    I am getting a block size error (16) with some of the DB files I try to process. Just in case someone ran into the same issue and has a solution.
    Tom, I sent you an email with a sample.
    Thanks,
    Marc

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.