ElasticSearch学习笔记-相关度得分记录

最近想要修改调整一下ElasticSearch里面Doc的Score，因而在ES官网查阅了一下，相关的介绍和说明仍是很是详细的，能作的修改调整也仍是比较多的，须要根据具体的情形去选择相应的方式作合适的调整修改，这里作个简单的记录，以便后续使用方便。

相关解释描述能够参考链接：

https://www.elastic.co/guide/cn/elasticsearch/guide/current/controlling-relevance.html

https://www.elastic.co/guide/cn/elasticsearch/guide/current/function-score-query.html

https://www.elastic.co/guide/cn/elasticsearch/guide/current/boosting-by-popularity.html

https://www.elastic.co/guide/cn/elasticsearch/guide/current/function-score-filters.html

https://www.elastic.co/guide/cn/elasticsearch/guide/current/random-scoring.html

https://www.elastic.co/guide/cn/elasticsearch/guide/current/decay-functions.html

https://www.elastic.co/guide/cn/elasticsearch/guide/current/script-score.html

 

如下是API操做的部分记录：

 

ScoreFunctionBuilder scoreFunctionBuilder = 
ScoreFunctionBuilders.fieldValueFactorFunction(fieldName)
	.factor(boostFactor).modifier(modifier).missing(missing).setWeight(weight);
线性衰减函数  一旦直线与横轴 0 相交，全部其余值的评分都是 0.0
ScoreFunctionBuilders.linearDecayFunction(fieldName, origin, scale)
	.setDecay(decay).setOffset(offset).setWeight(weight)
指数衰减函数  先剧烈衰减而后变缓 
ScoreFunctionBuilders.exponentialDecayFunction(fieldName, origin, scale)
	.setDecay(decay).setOffset(offset).setWeight(weight)
高斯衰减函数  高斯函数是钟形的——它的衰减速率是先缓慢，而后变快，最后又放缓。
ScoreFunctionBuilders.gaussDecayFunction(fieldName, origin, scale)
	.setDecay(decay).setOffset(offset).setWeight(weight)
origin  中心点或字段可能的最佳值，落在原点 origin上的文档评分 _score 为满分 1.0 。
scale  衰减率，即一个文档从原点 origin下落时，评分 _score改变的速度。
decay  从原点 origin衰减到 scale所得的评分 _score，默认值为 0.5 。
offset  以原点 origin为中心点，为其设置一个非零的偏移量 offset覆盖一个范围，而不仅是单个原点。
	在范围 -offset <= origin <= +offset内的全部评分 _score 都是 1.0 。
随机评分
ScoreFunctionBuilders.randomFunction(seed)
权重因素
ScoreFunctionBuilders.weightFactorFunction(weight)

 

脚本评分

1. String timeField = getTypeTimeField(type);

2. if (StringUtils.isBlank(timeField)) {

3. searchRequestBuilder.setQuery(buildBoolQuery(params.keywords(), attributes));

4. } else {

5. String inlineScript = ElasticScriptUtils.scriptWithScoreAndTime(timeField, System.currentTimeMillis());

6. Map<String, Object> sparams = new HashMap<>();

7. Script script = new Script(inlineScript, ScriptType.INLINE, "groovy", sparams);

8. ScoreFunctionBuilder scoreFunctionBuilder = ScoreFunctionBuilders.scriptFunction(script);

9. searchRequestBuilder.setQuery(QueryBuilders.functionScoreQuery(

10. buildBoolQuery(params.keywords(), attributes), scoreFunctionBuilder));

11. }

 

1. public class ElasticScriptUtils {

2.  

3. public static String scriptWithScoreAndTimeV1(String field, long currentTime) {

4. String script = ""

5. + "field = (null==_source." + field + "?\"1970-01-01 12:00:00\":source." + field + ");"

6. + "format = \"\";"

7. + "ds = field.trim().split(\":\");"

8. + "if (ds.length == 3) {"

9. + " format = \"yyyy-MM-dd HH:mm:ss\";"

10. + "} else if (ds.length == 2) {"

11. + " format = \"yyyy-MM-dd HH:mm\";"

12. + "} else if (ds.length == 1) {"

13. + " ds = d.trim().split(\" \");"

14. + " if (ds.length == 2) {"

15. + " format = \"yyyy-MM-dd HH\";"

16. + " } else if (ds.length == 1) {"

17. + " ds = d.trim().split(\"-\");"

18. + " if (ds.length == 3) {"

19. + " format = \"yyyy-MM-dd\";"

20. + " } else if (ds.length == 2) {"

21. + " format = \"yyyy-MM\";"

22. + " } else if (ds.length == 1) {"

23. + " format = \"yyyy\";"

24. + " }"

25. + " }"

26. + "};"

27. + "parse_date = Date.parse(format, field).getTime();"

28. + "return _score.doubleValue() + (parse_date / " + currentTime + ");";

29. return script;

30. }

31.  

32. public static String scriptWithScoreAndTime(String fields, long currentTime) {

33. String script = ""

34. + "temp_fields = \"" + fields + "\".trim().split(\",\");"

35. + "target_field = temp_fields[0];"

36. + "temp_field = _source.target_field;"

37. + "for (i in 2.. temp_fields.length) {"

38. + " if (null != temp_field) break;"

39. + " target_field = temp_fields[i-1];"

40. + " temp_field = _source.target_field;"

41. + "};"

42. + "field = (null==temp_field ? \"1970-01-01 12:00:00\" : temp_field);"

43. + "format = \"\";"

44. + "ds = field.trim().split(\":\");"

45. + "if (ds.length == 3) {"

46. + " format = \"yyyy-MM-dd HH:mm:ss\";"

47. + "} else if (ds.length == 2) {"

48. + " format = \"yyyy-MM-dd HH:mm\";"

49. + "} else if (ds.length == 1) {"

50. + " ds = d.trim().split(\" \");"

51. + " if (ds.length == 2) {"

52. + " format = \"yyyy-MM-dd HH\";"

53. + " } else if (ds.length == 1) {"

54. + " ds = d.trim().split(\"-\");"

55. + " if (ds.length == 3) {"

56. + " format = \"yyyy-MM-dd\";"

57. + " } else if (ds.length == 2) {"

58. + " format = \"yyyy-MM\";"

59. + " } else if (ds.length == 1) {"

60. + " format = \"yyyy\";"

61. + " }"

62. + " }"

63. + "};"

64. + "parse_date = Date.parse(format, field).getTime();"

65. /**

66. + "println _score.doubleValue(); println (parse_date / " + currentTime + ");"

67. **/

68. + "return _score.doubleValue() + (parse_date / " + currentTime + ");";

69. return script;

70. }

71.  

 

https://www.elastic.co/guide/cn/elasticsearch/guide/current/decay-functions.html