Exam02 Joins

Joins and Relates (9)

Questions

1. What is the difference between a join and a relate?
2. What is the difference between one-to-one, one-to-many, many-to-one relationships of data tables?

Tasks

1. Open a blank map and add countries from Exercise 3.
2. Add the "Data" worksheet from the data table HigherEducationData2002 (data source: NSF) in the Exam02 folder.
3. Examine both data files. How many countries in the geographic layer? How many in the education data table?
4. What field names contain country names in the two files?
5. Do a join between them using these fields. Keep only records that match (so that we can track how many do match).
6. What would you suggest as the next step if you were trying to create this as a research data set?

1. Add a fresh copy of countries to the map, color its polygons light grey with no borders and move it to the bottom.
2. Make a shade by quantity map of the data using the field that gives ratio of first university degrees to size of 24 year old population.

+ classmate instructions

Chapter 9: Joining and relating tables

Exercise 9a Joining tables

• Add database file
• Right click the layer, on the context menu click on "Joins and relates" and click "Join"
• Make sure "Join attributes from a table is selected"
• In the drop-down list #1, click IDNUMBER
• In the drop-down list #2, click the layer you wish to join
• In the drop-down list #3, make sure the IDNUMBER is chosen again
• Discuss different
• Choose "keep all records" or "keep matching records" based on data

Exercise 9b Relating tables

• Add database file
• Right click the layer, on the context menu click on "Joins and relates" and click "Relate"
• In the drop-down list #1, click IDNUMBER
• In the drop-down list #2, click the layer you wish to relate
• In the drop-down list #3, make sure the IDNUMBER is chosen again
• In the drop-down list #4, create a name for the related tables, then click OK

GOOD LUCK!!! <3