While i'm create a simple object class in Map3D, i can choose in the Properties List from the available properties, or create my own. If i create a new custom property, i can choose in the drop down list from these data types: Text String, Integer, 3D point, Real, Boolean (Yes/No). If i choose the Integer type, i can't set the default value to NULL. - these settings displayes on the "Define Object Classification" window.
After creating the object class, and run the classification, i can't set my Custom property on the classified CAD object to NULL (Properties pane), it would be very important.
Any Idea, or method to create Nullable Custom Object Data field?
Integers are whole numbers that do not contain a decimal point, therefore it requires a value. If you want it as NULL set it as a string.
Thank you for your reply, Murph!
This is a problem for me, because set the datatype to string isn't an option. How to set NO DATA value without nullable integer data type?
Unfortunately using Text-String isn't a good solution, because i want to move my data into postgis database. As i know, the whole "Object Data concept" was made to move simple CAD objects to GIS datastore. (define classes, classification CAD objects, export the classified CAD data via mapexport or bulk copy into GIS datastores). I can't understand, how can i do this workflow successfully without nullable integer OD fields.
I need to create a GIS database, which contains streets, and they are stored the number of parking places.
Suppose that, i get the streets like CAD polylines, so i need to create my own object class, which has only one custom field: parkingplaces
- If the parkingplaces field is integer: i can't set the NO DATA value, because the '0' is a value too
- If the parkingplaces field is text: i can set the NO DATA value, but few problems comes later:
- The user type accidental text, instead of number
- While copying the CAD objects with bulk copy, i need to choose the fields in a drop down list in the From, and of course the To side. My field types will different, because in the datastore the parkingplaces field is an integer. Set the datatype to text in the datastore isn't an option. How can i running spatial query, create statistic, create thematic maps on a text field? Not at all.
>> If the parkingplaces field is integer: i can't set the NO DATA value, because the '0' is a value too
If a "NULL"-value is allowed or not depends on the type of database, not all databases support a NULL value for integers (or even any numeric value).
And I do understand that you have to differentiate between the two states:
And now you have two chances:
Just my 2c, - alfred -