To learn more about how to create relationships and use Lookup and Summary columns, see the next article about "How to use relationships".
Table relationships in concept
Relationships are really powerful concepts in Tables -- they are derived from traditional database table "relationships" or "references". This section will give you a brief outline of relationships and what you can do with them.
Say you have two tables of data: a table of “People”, and a table of “Countries”. Each of the rows in these tables is what we call a “record”, and the individuals in the “People” table records can be related to the countries in the “Countries” table in different ways.
Let’s say we want to track citizenship for each person. Here’s how it might look below; you can now see a new “Citizenship ↳ Country” column in the People table that shows the countries that the people are citizens of. Each country in the “Country” column in the People table “refers to” a country in the Countries table -- meaning any value in that column must come from one of the records in the Countries table -- and we do this by creating a new “Citizenship” relationship in the People table that “links to” the Countries table and pulls in the “Name” column.
Note: since Mar '21, we now generate the relationship name automatically using the table names, and you should simply title the column "Citizenship country" instead, but overall relationship concepts are still the same.
Having this table relationship allows us to pull in more data from the Countries table if needed:
Multiple table relationships
We can also create multiple relationships to represent the different ways data are related, and in this case, we can also track country of residence for each person with another relationship:
Summarizing or aggregating related information
These relationships allow you to connect your data together in ways that reflect the nuance and complexity of how information relates to each other. By connecting your data together via these table relationships, you’re able to update data in one place and have it reflect everywhere it’s linked, and also perform powerful aggregation or summarization functions:
To learn more about how to create relationships and use Lookup and Summary columns, see the next article about "How to use relationships".