Apache Solr按功能排序

Question

Trying to sort a query by a field closest to today. From what i understand the sub function only allows references to the document. Is it possible to perform this via other means?

This is the error returned by Solr: sort param could not be parsed as a query, and is not a field that exists in the index: sub(NOW,StartDate)','code'=>400}}

eg sort=sub(NOW, StartDate) asc

Answer 1

Use the ms function if you're planning to do arithmetic operations on dates. This will convert the date to an integer.

In fact, the examples for ms shows exactly what you're trying to do:

ms(NOW,mydatefield)

.. which is described as

ms(a,b) : Returns the number of milliseconds that b occurs before a (that is, a - b)