Get to know ArcPad AXF

Get to Know ArcPad AXF

June 17th, 2008 · 22 Comments · GIS

The excellent ArcPad Team Blog has info on the new storage format for ArcPad 7.1.

Prior to ArcPad 7.1, shapefiles were ArcPad’s most common spatial file format for features. Shapefiles are great for many applications, but shapefiles lack the capabilities to support more sophisticated relational database requirments that exist in the ArcGIS Geodatabase. So ArcPad 7.1 introduced the AXF format, which we like to refer to as a “lightweight geodatabase”.

As a user of ArcPad at my old job, I really hated storing information in the shapefile format. Actually I hate shapefiles, period. Any format that requires you to maintain at least 3 separate files to ensure they work is a bad idea in my book. I liked that the ArcPad team build upon the Microsoft’s SQL Server Compact Edition platform.

Time to bury the shapefile format!

Tags: ArcPad·ESRI·geodatabase·shapefiles·sqlserver

22 responses so far ↓

1 Cellulose // Jun 17, 2008 at 10:10 pm

And use GML as the next spatial data format for exchanging data across vendors?
2 James Fee // Jun 18, 2008 at 6:17 am

GML, KML anything but shapefile.
3 MarkB // Jun 18, 2008 at 8:04 am

I very much appreciate the power and abstraction that ESRI’s various geodatabase formats provide. But, what other widespread, open, and file-based binary storage formats exist?

And, to play devil’s advocate, is the file geodatabase conceptually all that different in maintenance from the shapefile (of course I know better than that).

File Geodatabase (from ESRI):
“A collection of various types of GIS datasets held in a file system folder
This is the recommended native data format for ArcGIS stored and managed in a file system folder.”
4 John Reiser // Jun 18, 2008 at 8:08 am

Why Microsoft? Why not something open like SQLite? It has spatial extensions…
5 atanas entchev // Jun 18, 2008 at 8:09 am

Too many GIS formats. Way too many. I don’t care for the shapefile, but it has (had) one thing going for it that no other GIS format has — it came as close to a “standard” as any GIS format ever did.

It looks to me like ESRI is lost. Releasing new data formats is the last thing they need to do. Google will drink ESRI’s milkshake with KML. If it hasn’t already.
6 blizzardice // Jun 18, 2008 at 8:18 am

Will the other ESRI products support SQLCE or just ArcPad. If so it might work. But do we support that or GML/KML? Can KML do the more advanced stuff that ESRI switched to SQLCE for?
7 central_meridian // Jun 18, 2008 at 8:55 am

Until ESRI publishes a free API to the file geodatabase (as promised), the shapefile is here to stay as a data-distribution format. Last I heard we aren’t slated to see the File Geodatabase API until ArcGIS 10.

I would love to be using the file geodatabase more, but you can’t do anything with it unless you have access to ArcEngine/ArcObjects - which I do but my “customers” (read: the public) do not. ESRI could have owned the next gen GIS data format but now it is probably too late.
8 Regina // Jun 18, 2008 at 10:13 am

Can KML and GML use indexes? I didn’t think it could which would make it a poor storage for doing real gis work.

I don’t like SQLite all that much either. Something about its limitation on data types and the fact it doesn’t even validate that bothers the DB programmer in me.

I’m actually thinking FireBird is looking pretty darn good as something that is light enough to be portable and SQL perspective ANSI compliant rich enough to be cool. All it needs is someone to port GIS functionality to it. Although this is just all from what I read. Still need to try it out to see if the reality matches the fantasy.
9 James Fee // Jun 18, 2008 at 10:24 am

I find it curious the negative reaction to extending the geodatabase to Windows CE devices.

Given the hardship of moving from ArcSDE to ArcPad devices in the past, I for one was jumping up and down when I heard about this at the Dev Summit.

@atanas: I’m assuming you don’t use ArcPad that much as you’d be very unhappy with the ability to store data on mobile devices until now. As far as ArcGIS users are concerned, this is just one more way to extend the Geodatabase and will be seamless for those users. I’m just not sure anyone outside of ArcPad users needs to care about it.
10 atanas entchev // Jun 18, 2008 at 10:35 am

@James: You are correct, I am not a heavy ArcPad user. But I do care about system architecture, and the role mobile devices play in the grand scheme of things. Mobile devices have to be, first and foremost, simple and easy to use. Otherwise they get “accidentally” run over by the truck all too frequently.

Leica Geosystems has an interesting approach to “mobile” computing. Their MobileMatriX software sits on top of ArcGIS and allows users with laptops to collect data in the field directly in the geodatabase.

I am not crazy about either approach. Leica’s MMX is somewhat of a behemoth, while ArcPad is somewhat flaky, methinks.
11 blizzardice // Jun 18, 2008 at 10:58 am

I think the conversation has turned more into a death to shapefile conversation than an arcPad one. I am all for the conversion and would actually like to see it pushed to all the ESRI products.
12 BigBoy // Jun 18, 2008 at 12:34 pm

@Atanas: Direct GPS for ArcView was similar in that GPS data was written directly to a shapefile while you watched in on your laptop in the field. Can’t remember the manufacturer’s name.
13 Nico // Jun 18, 2008 at 3:01 pm

It’s great that they got the Attribute Domains - Subtypes built into the AXF, and Relates (as limited as they are in 7.1) are a huge improvement.
Question: what other programs can read AXF? If Arcpad and Arcpad Toolbar for Arcmap can’t read the file what do we do? Files get corrupted when batteries die on these portable devices, and correction files (.SSF) can get out of sync with the corrupted geographical file. I found out the hard way that Arcpad v6.
It’s interesting to learn that it’s SQLCE — maybe that means that some Microsoft product can read AXF if the ESRI products cannot.
You can do an AXF Data dump in Arcpad Studio 7.1 but that’s about it.
14 Elvin // Jun 19, 2008 at 7:09 am

Nico, because AXF files are SQL CE databases you have a range of options beyond ArcPad that can work with them, including :-

* MS SQL Server Management Studio

* ADO.NET objects (includes desktop and compact frameworks)

* OLEDB COM objects

* Growing range of 3rd party products (eg. http://www.primeworks-mobile.com/ )

* ArcPad Studio also has a ‘repair’ option available
15 Dejan // Jun 20, 2008 at 12:54 am

I really hope that support of a Shapefile will maintain in the future releases of ArcPad or at least there will be a free conversion utility AXF -> SHP and vice versa.

I got a response from ESRI 2 yrs ago about AXF and there are no plans to write a technical documentation about the file type format like for the Shapefile. I miss that.

Many customers are non-ESRI desktop users and I am affraid that ESRI can loose them easily. However, I was expecting from AXF much more than only the RDBMS in a compact edition, but also basic topology support (e.g. at least the simple edge geometric network rule, where every line has to have two points).

I have been always happy to see in the product the co-operation of the ArcPad team with the rest of the ESRI departments. Hopefully this will maintain in this way.

Cheers,
Dejan
16 Cellulose // Jun 20, 2008 at 7:36 am

With as hard as ESRI is pushing the ST_GEOMETRY, why isn’t the internal storage format of the AXF the ST_GEOMETRY? As I recall, the shapefile can’t represent curves and a few other concepts the same way that a GDB can.

If we’re going to kill the shapefile eventually, why continue letting it dictate future technology?
17 Evan // Jun 20, 2008 at 3:57 pm

I give the axf a hand-raise and a ‘yea’ if for no other reason than it’s a single file that can hold multiple feature layers as well as forms and scripts. The installation of my ArcPad project in the bad old days with multiple shapefiles, dbfs, and vbs files was a real pain and confused users to no end.
18 James Fee // Jun 21, 2008 at 9:47 am

@atanas:

Leica Geosystems has an interesting approach to “mobile” computing. Their MobileMatriX software sits on top of ArcGIS and allows users with laptops to collect data in the field directly in the geodatabase.

Bringing the geodatabase to a TabletPC is much different than bringing a database to WindowsCE.

The bottom line is if you want to bring a geodatabase to WindowsCE, you use the best product to handle databases on WindowsCE, Microsoft’s SQL Server Compact Edition.
19 atanas entchev // Jun 21, 2008 at 10:10 am

@James: Of course it is different.

From a system design standpoint, the question is not how to bring the geodatabase to WindowsCE, or whether we use WindowsCE, Vista, Linux, or AuntMildred’sAmazin’Home-MadeOSan’Stuff. The question is: How do we make our field operations more efficient? If (if) the answer is WindowsCE, then use AXF, I guess.
20 Joseph Wallis // Jun 24, 2008 at 5:07 pm

and just 3 years ago I was being told by ESRI that mobile devices couldn’t handle databases…glad they figured it out!
21 Dale Lutz // Jun 28, 2008 at 11:05 am

At the risk of chiming in a bit late, as someone who’s seen many different formats and schemas in my day, I have to say that there is a lot to like in how the AXF format is done, particularly how the domains and subtypes have been structured. We’ll have to figure out a way to get FME working with it soon….
22 James Fee // Jun 30, 2008 at 1:46 pm

Glad to hear you guys are keeping an eye on AXF. More geodatabase support is always welcome Dale!