Queries vs. Filters

Question

I can\'t see any description of when I should use a query or a filter or some combination of the two. What is the difference between them? Can anyone please explain?

Answer 1

Basically, a query is used when you want to perform a search on your documents with scoring. And filters are used to narrow down the set of results obtained by using query. Filters are boolean.

For example say you have an index of restaurants something like zomato. Now you want to search for restaurants that serve 'pizza', which is basically your search keyword.

So you will use query to find all the documents containing "pizza" and some results will obtained.

Say now you want list of restaurant that serves pizza and has rating of atleast 4.0.

So what you will have to do is use the keyword "pizza" in your query and apply the filter for rating as 4.0.

What happens is that filters are usually applied on the results obtained by querying your index.