Converting XML to FoxPro tables


Many FoxPro developers are familiar with XMLTOCURSOR() which converts an XML file to a FoxPro cursor for review. This function works typically best with a single table in an XML file.

Unfortunately, it requires a fairly well structured XML file. For example, it can parse this XML perfectly:
<?xml version = "1.0" encoding="Windows-1252" standalone="yes"?>
<vines>
    <vine_lot>
        <id>1</id>
        <ripe_grape>4</ripe_grape>
    </vine_lot>
    <vine_lot>
        <id>2</id>
        <ripe_grape>3</ripe_grape>
    </vine_lot>
    <vine_lot>
        <id>3</id>
        <ripe_grape>3</ripe_grape>
    </vine_lot>
</vines>

Yet, it complains when trying to convert:
<?xml version = "1.0" encoding="Windows-1252" standalone="yes"?>
<vines>
     <Lot>
          <id>1</id>
           <ripe-grape>4</ripe-grape>
     </Lot>
     <Lot>
          <id>2</id>
           <ripe-grape>3</ripe-grape>
     </Lot>
     <Lot>
          <id>3</id>
           <ripe-grape>3</ripe-grape>
     </Lot>
</vines>

Now the reason may be obvious to FoxPro developers - (ripe-grape is not a valid field while ripe_grape is) - so clearly you have to be very careful when using XMLTOCURSOR.


This program (Advanced XML Converter) will take nested XML tables and create multiple DBF files with it (as well as other formats) - it also deals with these types of issues.

I tried it out because I'm always interested in handling different XML formats. I could likely transform a nested XML into a single one with an XSL but this seemed a little easier.

For those who are unsure what I mean by a nested table, here is a sample (borrowed from here):

<Vineyard>
      <Lot id="1">
           <ripe-grapes>4</ripe-grapes>
           <Picker>
                 <name>John</name>
                 <metabolism>2</metabolism>
                 <grape-wealth>20</grape-wealth>
           </Picker>
     </Lot>
<Vineyard>

In this scenario, you would see two tables: Lots and Pickers.

Advanced XML Converter saw this and when I saved it as "Vine" it created two DBF files: Vine_Lots and Vine_pickers.

Unfortunately, what it missed was the relationship between Lots and Pickers.

I would have expected to see an foreign key in Pickers that would link it back to Lot. Unfortunately, it missed this relationship. To get it to work properly, I had to do:

<Vineyard>
      <Lot id="1">
           <ripe-grapes>4</ripe-grapes>
           <Picker id="2">
               <lot>1</lot>
                 <name>John</name>
                 <metabolism>2</metabolism>
                 <grape-wealth>20</grape-wealth>
           </Picker>
     </Lot>

Which defeats the purpose of the nested XML.

It's too bad - because it did a great job in other areas. Still, might be worth a look if you're looking to at least see what's up with it.

Here's my list of ERs:
1) properly handle relationships
2) build an XSL that will do the conversion for you automatically

Of course, that's not necessarily its purpose - it's more for data crunchers but without the relationship support for nested XML, it is lacking it.

Do you know of a tool that can do this? (either from a command line or others)


Software can turn raw data into structured text., HiBase Group

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