2021
LiliumCode - Spring Data Elasticsearch of 7 parts
    https://www.youtube.com/playlist?list=PLXy8DQl3058OoJqGLFdqoBkBKm2T0kS9B
    https://www.youtube.com/watch?v=IiZZAu2Qtp0
2020
Reelsen - Introduction into Elasticsearch & Spring Data Elasticsearch 0:00 of 1:20:09
    https://www.youtube.com/watch?v=84t_jC3dr3E
    https://noti.st/spinscale/YCsKrf/introduction-into-elasticsearch-spring-data-elasticsearch
        QueryBuilders
        https://spinscale.de/posts/2020-08-06-introduction-into-spring-data-elasticsearch.html
        https://noti.st/spinscale/YCsKrf/introduction-into-elasticsearch-spring-data-elasticsearch#ssINBth
            must
            filter
            mustNot
            SearchHit<Contribution>
            elasticSearchTemplate
            NativeSearchQuery
            Aggregations