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Creating Thematics on Query Results based on Object Type

  • 1.  Creating Thematics on Query Results based on Object Type

    Posted 05-11-2021 22:02
    I have a table which contains both plines and regions (but mostly plines)

    I want to create a two seperate thematic layers, one on the pline elements and another on the region elements.

    I run a two queries to seperate the object types into two layers (eg. str$(obj) = "pline" /  str$(obj) = "region")

    I can create a thematic layer on the plines, but when I try and create a thematic layer on the region query, it treats the layer as if it's got plines in it. I can can't choose the style for regions in the thematic settings.

    Is there anyway around this?  Can this be fixed, so that when I try and create an individual Region Thematic, it lets me choose region styles (like fill pattern)?



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    Kalu Ribush
    Manager Mapping Team
    Department of Transport
    Victoria, Australia
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  • 2.  RE: Creating Thematics on Query Results based on Object Type

    Posted 08-24-2021 06:11
    Hi Kalu

    This sounds a bit like a bug to me. Have you raised this with our support?
    They might say it works as designed but at least we can get it flagged as an issue

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    Peter Horsbøll Møller
    Principal Presales Consultant | Distinguished Engineer
    Precisely | Trust in Data
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  • 3.  RE: Creating Thematics on Query Results based on Object Type

    Posted 08-25-2021 08:31
    MIPro determines the theme style applied using the dominant object type in the table.
    We know the count of each object type in a table when you select a thematic template, so if the table contains more Polylines than Regions, and you select a Region based theme template, it will treat the theme with Polyline styles, etc. I'm assuming we are looking back at the base table the query was derived from when setting the thematic styles.  I would suggest separating these objects out into their own tables as a workaround if you can.  We can look at this code and see if there is a way to do this better with Query tables, but it could get a bit hairy with changing this.  Perhaps we need to revisit how\why we have to use the dominant object type in the table to determine styles with theme templates.
    Not a good practice for GIS in general to mix object types in a table, but sometimes it can't be avoided, and MIPro lets you do this obviously if required.  I don't believe this has changed since we implemented theme templates back in version 4.x or 5.x (I forget which version exactly).

    Thx,
    -Bill

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    Bill Wemple
    Principal Software Engineer, Quality Management
    Precisely, Inc
    precisely.com
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  • 4.  RE: Creating Thematics on Query Results based on Object Type

    Posted 08-25-2021 19:18
    Hi Peter and Bill

    Thanks for your responses.  Your explanation is as I expected.  I take your point Bill about not mixing object types in a table, but sometimes it's really convenient to do this.  For example we have a table of transport projects, which could be represented as points/lines/polygons, and it's much easier to maintain the attributes and perform analysis on one table than three.

    When it comes to creating a thematic map on features on the map, the style should really be dictated by the template that the user selects.  If I choose a point template, then the point objects in the layer should be style (and the others ignored).



    thanks

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    Kalu Ribush
    Manager Mapping Team
    Department of Transport
    Victoria, Australia
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