The app uses Views to filter data in a more advanced way.
A View allows to get all the documents matching specific conditions. For example, you can create a view called Recent books with a condition that matches books published after 2010.
Every condition is defined by a field (1), an operator (2) and a value (3).
In a condition, the operator defines the comparison type.
- Equal to, Greater than, Less than. They compare numbers, strings, booleans, dates and other field types.
- Contains. The condition is verified if the field's value contains the specified value. For example, Selection contains an item, Group contains a value, Text contains another text.
- Empty. The condition is verified if the field's value is empty.
You can combine multiple views through the exists operator.
The condition is verified if the linked document, defined by a document reference, exists in the secondary view.
For example, you can get all the Books by young authors with the exists operator and a secondary view Young authors that gets only the authors born after the 1990.
Exists operator is available for one-to-many relationships (Documents field) in the following variants: One exists if at least one document exists, and None exists if no document exists.