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859fba7c4b
MySQL supports DELETE with LIMIT and ORDER BY. https://dev.mysql.com/doc/refman/8.0/en/delete.html Before: ``` Post Destroy (1.0ms) DELETE FROM `posts` WHERE `posts`.`id` IN (SELECT `id` FROM (SELECT `posts`.`id` FROM `posts` WHERE `posts`.`author_id` = ? ORDER BY `posts`.`id` ASC LIMIT ?) __active_record_temp) [["author_id", 1], ["LIMIT", 1]] ``` After: ``` Post Destroy (0.4ms) DELETE FROM `posts` WHERE `posts`.`author_id` = ? ORDER BY `posts`.`id` ASC LIMIT ? [["author_id", 1], ["LIMIT", 1]] ```
67 lines
1.2 KiB
Ruby
67 lines
1.2 KiB
Ruby
# frozen_string_literal: true
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module Arel # :nodoc: all
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class TreeManager
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include Arel::FactoryMethods
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module StatementMethods
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def take(limit)
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@ast.limit = Nodes::Limit.new(Nodes.build_quoted(limit)) if limit
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self
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end
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def order(*expr)
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@ast.orders = expr
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self
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end
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def key=(key)
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@ast.key = Nodes.build_quoted(key)
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end
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def key
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@ast.key
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end
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def wheres=(exprs)
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@ast.wheres = exprs
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end
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def where(expr)
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@ast.wheres << expr
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self
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end
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end
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attr_reader :ast
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def initialize
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@ctx = nil
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end
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def to_dot
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collector = Arel::Collectors::PlainString.new
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collector = Visitors::Dot.new.accept @ast, collector
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collector.value
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end
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def to_sql(engine = Table.engine)
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collector = Arel::Collectors::SQLString.new
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collector = engine.connection.visitor.accept @ast, collector
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collector.value
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end
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def initialize_copy(other)
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super
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@ast = @ast.clone
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end
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def where(expr)
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if Arel::TreeManager === expr
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expr = expr.ast
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end
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@ctx.wheres << expr
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self
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end
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end
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end
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