Saturday, July 27, 2013
On Saturday, July 27, 2013 4:22:26 AM UTC+1, marcin longlastname wrote:
So instead, it seems I have to order the entire table first, then pluck, and then getting the last few rows. This seems extremely inefficient since I have to order all rows of it first, even though I am specifically using pluck over select for performance and memory reasons. Does anyone have any suggestions or ideas for a higher performance method of getting the a specific column of the last few rows of a table ordered by the primary key? I also extremely reccomend mentioning in the pluck API documentation that pluck returns an un-ordered list so others do not fall into the same mistake I did.
Timed.asset.order('id desc').limit(10).pluck(:id)
In general if you haven't specified an order then no order is applied. First is an exception rather than the rule here.
Fred
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