View Source Dequel (Dequel v0.7.0)
Dequel - A friendly query language
Query Adapters
Use Dequel.where/1 to convert queries to Ecto dynamic expressions:
Book
|> where(^Dequel.where("author.country:DE tags{name:fiction}"))
|> Repo.all()In-Memory Matching
For auto-updating saved queries, use matches?/2 to test preloaded structs:
book = Repo.get(Book, 1) |> Repo.preload([:author, :tags])
Dequel.matches?(book, "author.country:DE")
# => true or falseUse preloads/1 to get the required preloads for a query:
Dequel.preloads("author.country:DE tags{name:fiction}")
# => [:author, :tags]Summary
Functions
Tests if a struct matches a Dequel query.
Accepts a struct with preloaded associations and a query (string or AST). Returns true if the struct matches all conditions.
Examples
book = Repo.get(Book, 1) |> Repo.preload([:author])
Dequel.matches?(book, "author.country:UK")
# => true
Dequel.matches?(book, "title:*Rings author.country:UK")
# => true if title contains "Rings" AND author is from UKPreload Requirements
All associations referenced in the query must be preloaded. Use preloads/1
to get the required preloads:
preloads = Dequel.preloads(query)
book = Repo.preload(book, preloads)
Dequel.matches?(book, query)Raises Dequel.PreloadRequiredError if an association isn't loaded.
Extracts required preloads from a query.
Returns an Ecto-compatible preload list that can be passed to Repo.preload/2.
Examples
Dequel.preloads("author.name:Tolkien")
# => [:author]
Dequel.preloads("author.publisher.name:Penguin")
# => [author: :publisher]
Dequel.preloads("tags{name:fiction}")
# => [:tags]
Dequel.preloads("author.country:UK tags{name:fiction}")
# => [:author, :tags]