I remember when I first looked into Base, before I had any real knowledge of the theory of databases, and I looked for the feature you’re looking for. It doesn’t exist, but there is a better way to accomplish the same thing. Let me explain:
First, you should understand “primary keys” and “foreign keys”. If you are kind of fuzzy on understanding those, or don’t instantly know exactly what they are and what is the difference between them, read this tutorial until you get enough theoretical background.
Now, I’ll describe the feature the way I imagined it, before I knew anything about databases. I wanted to choose a name (first and last name) out of the “customers” table when inputting data into the “orders” table. I wanted a drop down list to show in the “customer” field of the “orders” table, which would concatenate the first and last names of each customer from the “customers” table.
If you understand primary keys, you will easily see that I didn’t understand them at the time.
The actual way to solve what I was attempting is to have a primary key in the “customers” table which would be an integer, not the names. In the “orders” table I would have a foreign key linked to the primary key of the “customers” table.
Of course, this would be utterly useless for entering information directly into the “orders” table, because I would have to just type in a number for the customer, and just remember that “customer #65536” is “Bob Jimson”. Not going to happen.
The rest of the answer is to make a FORM. In a form, NOT in a table, is where you can get your drop down boxes. The form can only be created after the “customers” and “orders” tables have both been created. It can be set up so when you go to enter a new order, using the form, you get a drop down list showing the first and last name of each customer. When you choose a customer from the list, that customer’s ID# (primary key) is entered in the “customer” column of the “orders” table (as a foreign key) for the order record you are creating.
The “how to” on this is covered quite well in the tutorial I linked to, but this should hopefully give you some idea of how the pieces fit together.
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