Accepted Data Types (DateTime, Geometry)

[Metron4]

We are using SQL Server to store our map data, inside tables that contain non-spatial data. I noticed a couple of things;

(1) Fields in SQL with the "date" data type do not show up in the Map 3D schema. Does Map only accept "datetime"? What do you do if the client only wants to see the date?

(2) Fields in SQL using the "geography" data type become "geometry" data types in Map. Perhaps this isn't a problem. We would like to store lat/long and easting/northing data. Do I need to create separate columns for this or is all this data stored in a single column using the "geometry" data type?

Thanks,

Rob

[phil_borycens · Accepted solution]

Hi Rob,

Thanks for your post. Here is some info for you:

1. The "Date" Data Type in SQL Server Spatial is not supported in AutoCAD Map 3D. So if you create a field on the SQL Server side with a Data Type of "Date", that column will be invisible in the AutoCAD Map 3D data Table for that feature class.

This is implied when creating a New Property in the Schema of a SQL Server Spatial feature class. You'll notice that Date is not one of the choices in the list:


2. Regarding your question about the difference between geometry and geography, I'm going to paste the text verbatim from the AutoCAD Map 3D user help:

SQL Server Spatial includes two spatial data types: geometry and geography. Geography is used for geodetic data, such as latitude/longitude data. Geometry is meant for all other spatial data. The two spatial data types support similar operations.

Geometric properties have a Geometry or Geography column, depending on the coordinate system of the associated spatial context for the property. If the coordinate system is geodetic, it has a Geography column. Otherwise, it has a Geometry column. A coordinate system is Geodetic if its “well known text” (WKT) starts with GEOGCS.

My own thought regarding this is this: if your feature class is *points* data, then you can use separate X and Y attribute fields to define its geometry (location in any coordinate system). If your feature class is lines or polygons, then it cannot be defined in attribute fields (the geometry of lines and polygons are too complex to be defined by a numeric value in an attribute field).

I hope this proves helpful.

[Metron4]

Thanks, Phil. It's good to have that verified so I am not running around wondering why I can't display dates.

Thanks,

Rob