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a738295805
Currently supported by PostgreSQL 9.4+ and SQLite 3.30+ See: - http://modern-sql.com/feature/filter - https://www.postgresql.org/docs/9.4/static/sql-expressions.html#SYNTAX-AGGREGATES - https://sqlite.org/lang_aggfunc.html#aggfilter Example: Model.all.pluck( Arel.star.count.as('records_total').to_sql, Arel.star.count.filter(Model.arel_table[:some_column].not_eq(nil)).as('records_filtered').to_sql, )
45 lines
965 B
Ruby
45 lines
965 B
Ruby
# frozen_string_literal: true
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module Arel # :nodoc: all
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module Nodes
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class Function < Arel::Nodes::NodeExpression
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include Arel::WindowPredications
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include Arel::FilterPredications
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attr_accessor :expressions, :alias, :distinct
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def initialize(expr, aliaz = nil)
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super()
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@expressions = expr
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@alias = aliaz && SqlLiteral.new(aliaz)
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@distinct = false
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end
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def as(aliaz)
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self.alias = SqlLiteral.new(aliaz)
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self
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end
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def hash
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[@expressions, @alias, @distinct].hash
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end
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def eql?(other)
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self.class == other.class &&
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self.expressions == other.expressions &&
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self.alias == other.alias &&
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self.distinct == other.distinct
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end
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alias :== :eql?
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end
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%w{
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Sum
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Exists
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Max
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Min
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Avg
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}.each do |name|
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const_set(name, Class.new(Function))
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end
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end
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end
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