Solved

Need help doing a dissolve in Oracle

Posted on 2011-02-22
4
1,025 Views
Last Modified: 2013-11-11
I am trying to dissolve a large number of polygons. In ArcGIS the operation simply was not practical so I am trying to do it in Oracle.  For my initial test I am trying this:

 SELECT TRANSTECH,MAXADDOWN,MAXADUP,HOCONAME,HOCONUM,SDO_AGGR_UNION(
  MDSYS.SDOAGGRTYPE(c.shape, 0.005))SHAPE
  FROM ADDRESS_EXTRACT_FC_BUFFER_RI c
  where c.objectid < 101
group by TRANSTECH,MAXADDOWN,MAXADUP,HOCONAME,HOCONUM,SHAPE;

But I am getting the following error:

ORA-22901: cannot compare VARRAY or LOB attributes of an object type
22901. 00000 -  "cannot compare nested table or VARRAY or LOB attributes of an object type"
*Cause:    Comparison of nested table or VARRAY or LOB attributes of an
           object type was attempted in the absence of a MAP or ORDER
           method.
*Action:   define a MAP or ORDER method for the object type.
Error at Line: 12 Column: 54

If I do the aggregate function on the shape column only  it works successfully.  I tried adding an ordered hint but no sucess either.

Any Ideas will be greatly appreciated.
Thanks,
0
Comment
Question by:OR1
4 Comments
 

Accepted Solution

by:
OR1 earned 0 total points
ID: 34954963
I got around the error I was having.  The statement runs without errors not and it gives me the same number of features I would expect from doing it with ArcGIS.  The problem I have now is that it is very slow. It took 1 hour to run on 3335 polygons. If there something I am doing wrong?

select TRANSTECH,MAXADDOWN,MAXADUP,HOCONUM,HOCONAME,SDO_AGGR_UNION(
  MDSYS.SDOAGGRTYPE(c.shape, 0.005))SHAPE
   FROM ADDRESS_EXTRACT_FC_BUFFER_RI c
  group by TRANSTECH,MAXADDOWN,MAXADUP,HOCONUM,HOCONAME;


Also I will have to convert this into something I can export to a new  geodatabase  feature class.  I was thinking about selecting the results of the query into a a table and register it later as a feature class. Does  that sound like the right approach?

Thanks,
0
 
LVL 5

Assisted Solution

by:mrfixit22
mrfixit22 earned 500 total points
ID: 34985603
you can use http://ss64.com/ora/syntax.html exp.  I would like to have the shape file to work with.
If you can let me know and I will give your a place to send it.
0

Featured Post

Gigs: Get Your Project Delivered by an Expert

Select from freelancers specializing in everything from database administration to programming, who have proven themselves as experts in their field. Hire the best, collaborate easily, pay securely and get projects done right.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Working with Network Access Control Lists in Oracle 11g (part 1) Part 2: http://www.e-e.com/A_9074.html So, you upgraded to a shiny new 11g database and all of a sudden every program that used UTL_MAIL, UTL_SMTP, UTL_TCP, UTL_HTTP or any oth…
How to Unravel a Tricky Query Introduction If you browse through the Oracle zones or any of the other database-related zones you'll come across some complicated solutions and sometimes you'll just have to wonder how anyone came up with them.  …
Video by: Steve
Using examples as well as descriptions, step through each of the common simple join types, explaining differences in syntax, differences in expected outputs and showing how the queries run along with the actual outputs based upon a simple set of dem…
This video shows how to Export data from an Oracle database using the Datapump Export Utility.  The corresponding Datapump Import utility is also discussed and demonstrated.

776 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question