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Vector Spatial Layers and End Product

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Due to the fact that data may not be available or missing, all fields in the two feature classes will accept a NULL value. Both feature classes have no default value because the input data is various. Field names and their data type are shown below:
→ Land_use: this will state the type of the buildings (Commercial, Residential or Public). For this field, short integer data type was associated with it in order to link the field with a table that holds the IDs for each type.
How will you associate a designation of the time period, 1920, with the feature classes you create? Be mindful of the integrity of your data versus considerations of data-redundancy. Justify your decision.
The only way to associate the time period is to add a field in both feature classes to feature the year of the building and the street, which will also help to avoid mixing different data because the project will cover 10-year intervals and there will be a large number of feature classes. Another way is to add the time period to the title of the shapefile, for example (streets_1920 or Buildings_1920)
In order to use the orthophoto file, the spatial reference should be defined too (UTM Zone 17 North, NAD83). This step could be done using ArcCatalog by entering the properties of the layer and then selecting the spatial reference from the projection folder. Another way to define the projection is by using the projection tool in Arc Toolbox.
The reason for not using the DRG file instead of the orthophoto is that the orthophoto file offers more detail to plot the control points, back to the higher resolution of the photo. For example, if it becomes necessary to add a control point where the primary school is, it would not be possible to use the DRG file because the location of the school would be hard to recognize.