Calculate and display a derived value
Conditionally hide or show content
Change display properties
Change the state of a view that is embedded on a different view or a page
Change a link URL
Change the text in a link
Set which roows are displayed
Change the options in a drop-down
Create a calculated field (stored or not stored)
Express that some rows are owned by users according to an expression that is more complicated than a simple field
The formula must return a value which is then used depending on where the formula is entered. Some examples:
You want to use a field in the current row to calculate a URL that you are linking to. An example Formula for an internal link could be: '/view/mypage?id='+id, and for an external URL 'https://en.wikipedia.org/wiki/'+wiki_page_name
You want to use a field name is the label for a link. If you have a field called name, then name is a valid formula.
You only want to show a section on rows where age is greater than 65. In the container settings, under Show if... formula, enter age>65
Any field in the current table, that is the table that the current view is based on, is available as a variable. You can also access join fields using dot notation. For instance, if the current table has a key field called author to the writers table, and the writers table has fields name and age, you can use the expression author.name in a formula
Where formulas in select field views and aggregations are very limited in the types of expressions they support, because they need to be checked for security and then translated to SQL. You can only use simple expressions such as name==="Foo" combined with &&, ||, !, <, >, <=. You can also state that two fields should be equal such as name===name2.