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  • 1.  Select statement is generating popup error message

    Posted 09-23-2020 14:20
      |   view attached
    We seem to have found a potential floating-point error in MIPro object operations.

    I've attached two MapInfo Pro vector tables, each of which has a single region object in it. One region object is entirely contained within the other, so there is a non-zero area overlap. However, when I run this query:

    Select Query2.ncessch, AreaOverlap(tile.obj, Query2.obj) "OverlapArea" from Query2, tile where Query2.Obj Intersects tile.Obj into qFail

    If I run this query and then try to open qFail in a browser, I get a popup error message that says: "You cannot Split, Erase or Overlay objects with a linear object."

    Can anyone explain why this is happening?

    Follow up note: If you zoom into the north west corner of the object in Query2, you see a very tiny and thin spur. If you remove the most northwest node (at the tip of the spur) and save the table, the query runs and the browser opens without error.



    ------------------------------
    Matthew Katinsky
    Senior GIS Programmer
    SCHLOSSER GEOGRAPHIC SYSTEMS
    Montpelier VT
    ------------------------------

    Attachment(s)

    zip
    Error.zip   5 KB 1 version


  • 2.  RE: Select statement is generating popup error message

    Posted 09-23-2020 18:24
    Hi Matthew,

    This seems to have to do with the name of your "Query2" table.  If you rename it the message will not appear.



    ------------------------------
    James Nolet
    Dooley Mitchell & Morrison Pty Ltd
    Mentone, VIC, Australia
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  • 3.  RE: Select statement is generating popup error message

    Posted 09-24-2020 10:19
    Thanks for looking! Unfortunately, that did not work for me. I saved the table with a new name "Reg.tab", closed Query2, opened the new table, and reran the query with the new table. I still got the popup error. Please keep in mind that the SELECT statement itself does not fail. I only get the error when I open a browser on the query table (qFail). It's as if the select statement is lazy loading (like a Javascript promise) and doesn't actually run  the AreaOverlap until I force it to display the calculated value.

    ------------------------------
    Matthew Katinsky
    Senior GIS Programmer
    Schlosser Geographic Systems
    Montpelier VT
    ------------------------------



  • 4.  RE: Select statement is generating popup error message

    Posted 09-25-2020 07:53
    Hi Matthew,

    I've taken another look.  Previously I suggested you "rename" the table, but I actually did a "Save Copy As", and saved to MapInfo Extended.  In MapInfo Extended format the query succeeds.

    Experimenting further, I found that there is an issue with the polygon in Query2.tab, and probably has to do with the strange slither you mentioned that is at the north west corner.  I tried editing the table by dragging nodes around, and the same "You cannot Split, Erase or Overlay objects with a linear object" error message appeared the first few times.

    So the solution is to either save as MapInfo Extended, or fix the polygon.  For example, deleting the north-most node of the slither is enough to remove the slither entirely and seems to fix the problem.


    ------------------------------
    James Nolet
    Dooley Mitchell & Morrison Pty Ltd
    Mentone, VIC, Australia
    ------------------------------



  • 5.  RE: Select statement is generating popup error message

    Employee
    Posted 09-25-2020 08:28
    That slice also looks a bit suspicious to me

    Notice how it doesn't seem to end at the same point even though it should be the same point.
    And no border between the "two" points at the top of the slice.


    ------------------------------
    Peter Horsbøll Møller
    Principal Presales Consultant | Distinguished Engineer
    Precisely | Trust in Data
    ------------------------------



  • 6.  RE: Select statement is generating popup error message

    Posted 09-25-2020 10:11
    Good eyes, James and Peter - thank you. When I am zoomed out enough that the oddity of the slice is not noticeable, you can select the one node at its tip and delete it. This will also fix the problem. I'll try the extended version idea.

    Is it likely that someone from Precisely will read this post and take up the issue, or should I formerly report this as a bug through tech support?

    ------------------------------
    Matthew Katinsky
    Senior GIS Programmer
    Schlosser Geographic Systems
    Montpelier VT
    ------------------------------



  • 7.  RE: Select statement is generating popup error message

    Posted 09-26-2020 08:30
    Peter will be able to advise better whether to report this as a bug, but it seems to me that MapInfo is doing its best to display a dodgy spatial object.  What is the source of the polygon?  Was it created in MapInfo or elsewhere?

    ------------------------------
    James Nolet
    Dooley Mitchell & Morrison Pty Ltd
    Mentone, VIC, Australia
    ------------------------------



  • 8.  RE: Select statement is generating popup error message

    Employee
    Posted 09-28-2020 04:20
    Hi Matt

    You can send it to our tech support if you want: PBS Software Support (software.support@pb.com). Tech Support won't pick up issues from the Community unless we ask them to.

    ------------------------------
    Peter Horsbøll Møller
    Principal Presales Consultant | Distinguished Engineer
    Precisely | Trust in Data
    ------------------------------