The creation of a geodatabase is one of the most important steps when creating and storing data. Geodatabases are the new frontier in geospatial data storage and allow us to easily store data in a neat, organized fashion with files that classify data and contain metadata.
Geodatabases also allow us to set domains ranges to our data. A domain range is the valid values for a particular element in the geodatabase. An example in our case would be temperature. This time of year we know temperature should be between -20 and 60 degrees, so by setting a range on the data it allows us to check for errors while inputting the data. On other field values, we can also set up coded values. These a predetermined values that you can choose from when entering data. These are helpful since it can eliminate typing errors and time while inputting.
Tutorial
The first step in creating a geodatabase is to open up ArcCatalog. In ArcCatalog, you will want to right click on the folder you wish to place the geodatabase in. From there you will want to select "New," then select a "New File Geodatabase" (Fig 1). Depending on the work you are preforming you can choose from either a Personal or File Geodatabase. With a Personal Geodatabase, the space is limited and it must also be stored and accessed in Microsoft Access. It is recommended in most cases to use a File Geodatabase.
Figure 1.
The geodatabase has now been created and can be seen in your designated folder (Fig 2). You will now want to created a new feature class in the designated geodatabase. This can be done by right clicking on the geodatabase and choosing "New" and "Feature Class" (Fig 3). You want to name the Feature Class and choose the type. In this case, we will use a point type feature class. The feature class should now be visible your geodatabase (Fig 4).
Figure 2.
Figure 3.
Figure 4.
The nest step in creating a geodatabase for deployment is the addition of domains. As recalled, a domain range is a set of valid values for the field. A coded domain may also be used to give a lost of choices during data collection. To start adding domains, you will want to right click on your geodatabase in the menu and choose properties (Fig 5). In the tabs on the Database Properties window, you will want to select Domains (Fig 6). To add domains, you will want to name the domain. This will must likely correlate to the data you will be using the domain for. An example for this exercise is wind direction. You can then enter a description of the domain for other users to see in case there are any questions about the domain. In the lower part of the window, there are the domain properties (Fig 6). This allows you to set the minimum and maximum values for the field, the field type (if numeric, text, etc.), and split and merger policies. For our example of wind direction, we will be measuring the direction from which the wind is coming from with a compass. True North will be 0 degrees. Since we will be using a compass, the minimum value will be 0 and the maximum will be 360 since there are only 360 degrees in a circle.
Figure 5.
Figure 6.
You can add as many domains as needed for the number of fields you have for data collection. Another option is a coded domain. By using a coded domain, a list of options appear for the field when collecting data. For this example, ground type will use a coded domain (Fig 7). By using the coded values option on the bottom, options can be entered like grass, concrete, etc. It is always important to enter a description of the code so that any user can use it for reference if questions occur.
Figure 7.
The next step is to apply these domains to your fields. By right clicking on the feature class and choosing properties, the Feature Class properties window will appear (Fig 8). In the Feature Class Properties window, you will want to add all of the fields of data you will be collecting (Fig 9). In this case, it includes wind speed, wind direction, humidity, temperature, ground cover, dew point, and wind chill. In the data type, you will want to choose the type of data that will be entered (Fig 10). This includes short integer, long integer and text. You will need to choose the correct type so that when data is entered, it is placed into the correct format (like how many decimal places to include).
Figure 8.
Figure 9.
Figure 10.
For each field, you will also be able to select the appropriate Field Properties (Fig 11). The Alias will show up as the name of the field as you specified above. You have the option to except null values if wished, and also specific a domain. When you click to specify a domain, a drop down lost will appear with all of the domains you added earlier (Fig 12). Choose the appropriate domain for each field type.
Figure 11.
Figure 12.
Now that all fields and domains have been applied, you are now ready to deploy the geodatabase and collect data!
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