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#
#  Author: Praveen Devarao <praveendrl@in.ibm.com>
#

module Arel
  module SqlCompiler
    class IBM_DBCompiler < GenericCompiler

      def limited_update_conditions(conditions, taken)
        quoted_primary_key = engine.quote_table_name(primary_key)
        update_conditions = "WHERE #{quoted_primary_key} IN (SELECT #{quoted_primary_key} FROM #{engine.connection.quote_table_name table.name} #{conditions} " #Note: - ')' not added, limit segment is to be appended
        engine.add_limit_offset!(update_conditions,{:limit=>taken,:offset=>nil})
        update_conditions << ")" # Close the sql segment
        update_conditions
      end

      def add_limit_on_delete(taken)
        raise "IBM_DB does not support limit on deletion" # Limiting the number of rows to be deleted is not supported by IBM_DB
      end

    end
  end
end