No. An index basically tells the search function where to search, so your searches happen faster.
For example, let’s say you have a word that you want to find in a dictionary. Say the word is “quaff”. What is the fastest way to find the word in the dictionary? You jump to the part of the book that starts with “Q”. How do you know which page is where Q starts? Most dictionaries have an alphabet index, which tells you things like “Q - page 324”. So you know to start searching at page 324.
The dictionary example from above is indexed by first letter.
You can index by day, so you are saying “Day 1: page 0, Day 2: page 5…”. It doesn’t change the comparison. It just changes the organization of the data so your query can return results fast.
The docs isn’t very clear on what @search(by: [day]) actually means. Is it by day (monday, tuesday, etc…), is it by day of month (1, 2, 3…31), is it by date up to the day (2020-01-01, 2020-01-02…). I will try to get that answered and amend the docs asap.