|
I may be wrong in some of the following – if so, please feel
free to correct it. I don’t use ESRI products. But I think that there are several people with misapprehensions about
the ESRI Geodatabase containers. Recent posts about a rejuvenated “Feature
Wish List” for MapInfo Professional have elicited these misleading ideas.
Richard Greenwood: > ESRI's personal geodatabase format is not exactly
'new', > it is actually being phased out, starting in 9.2 > with a new file-based format. I don't think
this is correct. The draft online ArcGIS 9.2 Desktop Help is a
good place to check this out – I would recommend that those who are even vaguely
interested start with “An
overview of the geodatabase” – last modified 6 October 2006. An ArcGIS geodatabase is a collection of geographic datasets of
various types held in a common file system folder, a Microsoft Access database,
or a multi-user relational database (such as Oracle, Microsoft SQL Server, or
IBM DB2). Also, this
section describes the types or variants of geodatabase: The geodatabase is a "container"
used to hold a collection of datasets. There are three types: 1.
File Geodatabases—Stored as folders in a file system. Each
dataset is held as a file that can scale up to 1 TB in size. This option is
recommended over personal geodatabases. 2.
Personal Geodatabases—All datasets are stored within a
Microsoft Access data file, which is limited in size to 2 GB. 3.
ArcSDE Geodatabases—Stored in a relational database using
Oracle, Microsoft SQL Server, IBM DB2, or IBM Informix. These multiuser
geodatabases require the use of ArcSDE and can be unlimited in size and numbers
of users. I would be
VERY surprised if ESRI is contemplating a change to the overall schema which
defines all of these. The XML Schema
document for the ESRI Geodatabase was published some time ago (2001 ? I think)
and AFAIK has been the basis of all of the “variants” described in
a fair amount of detail, in the online Help that I have referred to above. In my view, it
is an excellent and innovative design. It should also
be noted that “industry” geodatabases (of any of the 3 types or
variants) may be defined, all of which can conform to the underlying schema but
which may encompass unlimited (I believe) variation in detail. So, one
geological geodatabase may be designed for (say) mineral (gold, base metal,
etc) exploration, another for oil & gas, another for iron ore, another for
geochronology or for university research – and the XML Schema and the
package (the 3 variants described above) cater for these wide variations in
detailed database schemas. > The personal geodatabase (not to be confused with
SDE) > is built on the Microsoft Access MDB format. That IS true. > ERSI is moving toward a new, proprietary,
file-based personal > geodatabase format. ESRI uses the
same XML Schema for all forms of the GeoDatabase – see above. Chuck Lockwood
and others mention the (MI) Universal Translator, and Safe's FME product line.
As I read the Versions & Formats tables at Safe Software, in order to read
and create the various versions of the ESRI Geodatabase the various versions of
FME indeed DO require the corresponding ESRI products to be installed. That is
because (as far as I can tell, from reading the ESRI online manual for ArcGIS 9.2
Desktop Help fairly carefully) there are a lot more things (technical term)
stored within the geodatabase (whichever 'version') than just the geometry (eg,
SHP files or whatever), projections, datums, symbology, raster data sets, etc -
there is also the possibility of storing code and rules, and topology. It may
well be possible for FWTools (or some other gadget) to extract the former list
of components, but to assemble them into an ESRI “map” or other
rendition (eg, a surface) might require the code and the rules to operate (I’m
being rather vague about this). IL Thomas GeoSciSoft - -----Original Message----- On 10/22/06, Chuck Lockwood
<[EMAIL PROTECTED]> wrote: > Mat Elfstrőm's wish list specifies two items I
think are essential. Routing > capabilities and adding MapBasic to the core
product. I think the Universal > Translator should be updated and provisions made
to allow import and export > of ESRI's new geodatabase file format. ESRI's personal geodatabase format is not exactly
'new', it is actually being phased out, starting in 9.2 with a new
file-based format. The personal geodatabase (not to be confused
with SDE) is built on the Microsoft Access MDB format. ERSI is
moving toward a new, proprietary, file-based personal geodatabase format. As Bill T. pointed out, FW Tools supports the current
MDB geodatabase format (Although I have not tried it myself). And just for the record, I second the motion to
include an MB compiler w/ MI Pro. Rich -- Richard Greenwood [EMAIL PROTECTED] www.greenwoodmap.com |
_______________________________________________ MapInfo-L mailing list MapInfo-L@lists.directionsmag.com http://www.directionsmag.com/mailman/listinfo/mapinfo-l
