sth about solr and other opensource utils

solr

1 drill data by random,eg.&random_123

 solrQuery.addSortField("random_"+rand.nextInt(1000),SolrQuery.ORDER.desc);

2  search id not equal to 222

 eg.-id:222

3 deleteById(List<String> ids) in solrj

  we should delete anything by id As much as possible,using deleteByQuery function may occur some problem.

4 to get facet result we need to set facet and facet.field,also rows=0 is needed

5 if you use dismax to search,you should use q="val" instead of q="title:val"

6 highlight  params : &hl=true&hl.fl=title

7 show score params :&fl=score ,useful  score will  spread out before us when you search some words

8 delete url

   update/?stream.body=<delete><id>mm</id></delete>&stream.contentType=text/xml;charset=utf-8&commit=true

9 clear update docs

  after we commit docs,we need to use "this.docs.clear()"  to clear the queue stored docs

10 optimize

  optimizing one time per day is a good choice

11 get all the data which field value's length >0

   q=fieldName:["" To *]

12 use underline' can replace the default operator

   SolrQuery.setParam("q.op", "OR");

13 use dismax+qf to search instead of default text

14 url complex/analysis/field?q=param to get split words

15 if use mm, %25 is needed after urllink


16 query with q only will get better performance than 'q&fq'

json util

     we often use net.sf.json and org.json.simple to help us do explaining,on use we found some string cannot  be decoded well by  net.sf.json ,

so  org.json.simple is good complement .After import org.json we may use JSONParser to change string to JSONObject.

  For importing  net.sf.json,we may change list object to JSONArray,and decode json text to json object 

and then use a function(JSONObject.toBean(jsonObj,className)) to convert jsonObj to class object

    

原文地址:https://www.cnblogs.com/ai464068163/p/2375468.html