Crecto::Repo::Query

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Crecto::Repo::Query

The Query class provides building robust composable query builder for retrieving and manipulate data.
Generally (but not necessary), its easiest to define a shortcut variable at the top level of your application.
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Query = Crecto::Repo::Query
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The query object can be composed and manipulated before being used.
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query = Query.new
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query = query.where(is_admin: true) if role === "admin"
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query = query.where(is_user: true) if role === "user"
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Repo.all(User, query)
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Query methods
where
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Query.where(name: "Aaliyah").where(is_admin: false)
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or_where
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Query.where(role: "admin").or_where(role: "user")
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select
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Query.select(["id", "name"])
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limit
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Query.where(name: "Usher").limit(10)
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offset
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Query.where(name: "Aretha").limit(10).offset(10)
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order_by
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Query.order_by("created_at DESC")
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join
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# SELECT * FROM users INNER JOIN images ON images.user_id = users.id
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# WHERE images.file_name = ?
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class User
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  # schema ...
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  has_many :images
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end
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​
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class Image
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  schema "images" do
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    field :file_name
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  end
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​
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  belogns_to :user
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end
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query = Query.join(:images).where("images.file_name = ?", "crystal.jpg")
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Repo.all(User, query)
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distinct
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Query.distinct("users.name")
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group_by
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Query.where(name: "Charlize").join(:posts).group_by("users.id")
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preload
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Query.preload(:images)
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Nested grouped queries
and
With a block:
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query = Query.where(foo: "bar").and do |q|
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  q.where(name: "GZA").or_where(name: "RZA")
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end
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With multiple query objects:
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query = Query.where(foo: "bar").and(
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  Query.where(name: "GZA").or_where(name: "RZA")
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)
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Would both produce the same query from Repo.all(User, query):
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SELECT users.* FROM users WHERE ((users.foo='bar') AND ((users.name='GZA') OR (users.name='RZA')))
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or
With a block:
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query = Query.where(foo: "bar").or do |q|
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  q.where(foo: "baz").where(name: "ODB")
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end
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With multiple query objects:
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query = Query.where(foo: "bar").or(
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  Query.where(foo: "baz").where(name: "ODB")
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)
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Would both produce the same query from Repo.all(User, query):
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SELECT users.* FROM users WHERE ((users.foo='bar') OR ((users.foo='baz') AND (users.name='ODB')))
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