Question

我试图在我的mysql查询中内置动态订单，以便在顶部优先处理某些匹配。

Ticket.where(
  "id LIKE :search || name LIKE :search", 
  {search: "%#{params[:search]}]%"}
).order(
  "id = :exact DESC, name = :exact DESC, id LIKE :search DESC, name LIKE :search DESC", 
  {exact: params[:search], search: "%#{params[:search]}%"}
)

查询应该像这样假设params [：search] =＆＃39; search_value＆＃39;：

SELECT * FROM tickets
WHERE id LIKE "%search_value%" || name LIKE "%search_value%"
ORDER BY id = 'search_value' DESC, name = 'search_value' DESC, id LIKE "%search_value%" DESC, name LIKE "%search_value%" DESC;

我随时都这样做但是从ActiveRecord :: QueryMethods.validate_order_args收到错误，说明Direction应该是：asc或：desc。

除了手动清理搜索然后将其直接插入到顺序字符串中之外，有没有办法让它像where子句的绑定变量一样运行？

Answer 1

所以经过一番挖掘后我觉得我已经找到了解决方案，虽然我希望rails有更好的方法。

我已将其包含在我的rails项目中

class ActiveRecord::Base
  def self.corder *array
    statement = array.shift
    while (i=array.shift).present?
      case i
      when Hash
        i.each do |k,v|
          statement.gsub!(':' + k.to_s, ActiveRecord::Base.sanitize(v))
        end
      when String
        statement.sub!('?', ActiveRecord::Base.sanitize(i))
      else
        raise "Unknown type: #{i} -- #{i.class}"
      end
    end
    self.order(statement)
  end

  def corder *array
    statement = array.shift
    while (i=array.shift).present?
      case i
      when Hash
        i.each do |k,v|
          statement.gsub!(':' + k.to_s, sanitize(v))
        end
      when String
        statement.sub!('?', sanitize(i))
      else
        raise "Unknown type: #{i} -- #{i.class}"
      end
    end
    self.order!(statement)
  end
end

就我的目的而言，虽然可以很容易地扩展，但这种方法很有效。这两个是完全相同的（在类和实例上需要它的简单解决方案）。

此时你可以：

Model.where(
  'id LIKE :search || name LIKE :search', 
  {search: "%#{params[:search]}%"}
).order(
  'id = :exact DESC, name = :exact DESC, id LIKE :rough DESC, name LIKE :rough DESC', 
  {exact: params[:search], rough: "%#{params[:search]}%"}
)

SQL假设params [：search] ==＆＃39; ibm＆＃39;：

SELECT * FROM model WHERE id LIKE '%ibm%' || name LIKE '%ibm%' ORDER BY id = 'ibm' DESC, name = 'ibm' DESC, id LIKE '%ibm%' DESC, name LIKE '%ibm%' DESC;

或者＆＃39;？＆＃39;绑定变量也起作用，例如：

Model.where(
  'id LIKE ? || name LIKE ?', 
  "%#{params[:search]}%", "%#{params[:search]}%"
).order(
  'id = ? DESC, name = ? DESC, id LIKE ? DESC, name LIKE ? DESC', 
  params[:search], params[:search], "%#{params[:search]}%", "%#{params[:search]}%"
)

Rails 4 ActiveRecord查询：在order子句中绑定变量

1 个答案: