solr查询字段为空值,删除字段空值的方法

1. 例,我想查找内容字段content为空值的文档,看看文档有多少?执行如下查询.

http://127.0.0.1:11100/solr/province/select?q=-(content:*)&wt=json&indent=true

 2.删除域段空值:

http://127.0.0.1:11100/solr/province/update/?stream.body=<delete><query>-(content:*)</query></delete>&stream.contentType=text/xml;charset=utf-8&commit=true