I have been looking at the datatypes for MySQL but there is nothing really that I can see that mandates that input is either one thing or another. E.g. "option1" or "option2".
How might I do something like this when creating a table?
You can use enum datatype for restricting input within a range of values. Below is a sample table that shows the usage.
CREATE TABLE Sample
(
id int auto_increment primary key,
options enum('option1', 'option2')
);
The options field will only accept NULL, option1 OR option2 values. However, you can mark it NOT NULL as well.
You can further read the doco here