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  • Committer: Package Import Robot
  • Author(s): Dmitry Borodaenko, Dmitry Borodaenko, Cédric Boutillier
  • Date: 2013-08-10 18:38:17 UTC
  • mfrom: (1.1.8)
  • Revision ID: package-import@ubuntu.com-20130810183817-iqanz804j32i5myi
Tags: 4.1.1-1
[ Dmitry Borodaenko ]
* New upstream release.
* Standards-Version upgraded to 3.9.4 (no changes).
* Added Build-Depend on ruby-sqlite3.

[ Cédric Boutillier ]
* debian/control: remove obsolete DM-Upload-Allowed flag.
* use canonical URI in Vcs-* fields.
* debian/copyright: use DEP5 copyright-format/1.0 official URL for Format
  field.
* Update debian/watch. Thanks Bart Martens.

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lib/sequel/adapters/utils/emulate_offset_with_row_number.rb
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module Sequel
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  module EmulateOffsetWithRowNumber
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    # When a subselect that uses :offset is used in IN or NOT IN,
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    # use a nested subselect that only includes the first column
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    # instead of the ROW_NUMBER column added by the emulated offset support.
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    def complex_expression_sql_append(sql, op, args)
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      case op
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      when :IN, :"NOT IN"
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        ds = args.at(1)
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        if ds.is_a?(Sequel::Dataset) && ds.opts[:offset]
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          c = ds.opts[:select].first
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          case c
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          when Symbol
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            t, cl, a = split_symbol(c)
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            if a
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              c = SQL::Identifier.new(a)
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            elsif t
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              c = SQL::Identifier.new(cl)
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            end
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          when SQL::AliasedExpression
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            c = SQL::Identifier.new(c.aliaz)
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          when SQL::QualifiedIdentifier
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            c = SQL::Identifier.new(c.column)
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          end
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          super(sql, op, [args.at(0), ds.from_self.select(c)])
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        else
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          super
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        end
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      else
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        super
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      end
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    end
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    # Emulate OFFSET support with the ROW_NUMBER window function
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    # 
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    # The implementation is ugly, cloning the current dataset and modifying
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        raise(Error, "#{db.database_type} requires an order be provided if using an offset")
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      end
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      columns = clone(:append_sql=>'').columns
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      dsa1 = dataset_alias(1)
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      rn = row_number_column
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      sql = @opts[:append_sql] || ''
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        unordered.
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        select_append{ROW_NUMBER(:over, :order=>order){}.as(rn)}.
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        from_self(:alias=>dsa1).
 
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        select(*columns).
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        limit(@opts[:limit]).
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        where(SQL::Identifier.new(rn) > o).
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        order(rn))
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    def default_offset_order
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      clone(:append_sql=>'').columns
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    end
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    # This emulation adds an extra row number column that should be
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    # eliminated.
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    def offset_returns_row_number_column?
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      true
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    end
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  end
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end