The input location fields are set on the Input Locations dialog box. This is displayed by pressing the Set Columns button in the Input Columns box on the Database Parameters dialog box.
Locations can be specified using three different methods. These are specified using the Locations are: drop-down box on the Database Parameters dialog box. Locations can be specified using pushpins, street addresses (i.e. geocoding), or coordinates. Each method will result in a different appearance for the Input Locations dialog box. These are described separately below:
Setting Pushpin Locations
For pushpin locations, each source and destination location is specified using a text field that gives the name of a pushpin. The pushpins are found in the map file specified on the Database Parameters dialog box.
The Input Locations dialog box will look like this:
There are only two drop-down boxes that need to be set: select the data fields that store the pushpin names for the start and end locations (Source and Destination respectively, in this example).
Pushpin names should be unique. If two pushpins have the same name, there is no guarantee which pushpin will be returned by MapPoint.
Setting Coordinate Locations
For coordinate locations, each source and destination location is specified using geographic coordinate. This is specified by two fields (longitude, latitude) that use decimal degrees. Hemisphere conventions follow those of MapPoint and most GPS systems (North and East = Positive).
The Input Locations dialog box will look like this:
The longitude and latitude data fields must be specified for both the start and end locations.
Finally, you must specify a Primary Key. This can be any text or integer field with a set of unique values for each row. This might use an existing data field where this can be guaranteed, or more likely, it will be a database identifier code ("ID" in the above example). This field is used to ensure the correct data rows are updated with th calculated values.
Setting Street Address Locations
MPMileage can also geocode locations on-the-fly, converting street addresses into points on a map. This is potentially unreliable because geocoding will often have errors due to spelling mistakes or old road data. Therefore although this option can be very convenient, only use it when you know MapPoint can geocode your data satisfactorily. Otherwise, you should expect lots of location errors in your results.
The Input Locations dialog box will look like this:
A street address is specified using a number of different fields. Select all that are relevant and "<none>" for those where you do not have a data field. In the above example we do not have any Other city fields. Similarly, if you were only working with zipcodes, you would only set the Postcode (Zipcode) fields.
Most people will be working within one country, so it is usually best to set the Override Country to setting. This will set the country for ALL locations, and will hide the two Country fields. You would use the two Country fields if you wish to specify the country on a point-by-point basis - e.g. if you were routing across Western Europe.
Finally, you must specify a Primary Key. This can be any text or integer field with a set of unique values for each row. This might use an existing data field where this can be guaranteed (as above), or more likely, it will be a database identifier code. This field is used to ensure the correct data rows are updated with th calculated values.
