When I search in Elasticsearch, Elasticsearch send RESTAPI to original db?
Or Elasticsearch have orginal data?
I find Elasticsearch have indexing data. But I can't certain Elasticsearch have original data.
Elasticsearch is a database itself, so if you want some external data source to be in Elasticsearch (e.g: SQL Database) you need to index the data into Elasticsearch first, and then search against that data.
So no, the REST Api will not query against the original DB but against the data you have in Elasticsearch.
You can read more about the process here:
https://www.elastic.co/guide/en/cloud/current/ec-getting-started-search-use-cases-db-logstash.html
Related
I am trying to sync data between Bigquery and elasticsearch using the job template provided in GCP. The issue is that Bigquery sends all the documents everytime the job is run, now as elasticsearch has the document id as _id ,it creates duplicate documents.
Is there a way by which we can configure data _id field while sending data from bigquery to elasticsearch.
I'm using JanusGraph with ElasticSearch and Cassandra.
My question is how JanusGraph stores the data when I create a new entity in case that I'm using two databases (JanusGraph and ElasticSearch)
I could understand that ElasticSearch is used as index backend and Cassandra is the storage, but:
What JanusGraph does when I persist a new data ? It'll duplicate the same data into Cassandra and also on ElasticSearch (because it's also a database)?
If the answer for the first item is yes, so, when we perform a query that will traversal the graph, the JanusGraph will understand and perform the query on Cassandra and when this is a full text search then JanusGraph switch the query to ElasticSearch ?
If the answer for the first item is no, so, all the data will be stored on Cassandra and in some way JanusGraph will just use the index from ElasticSearch to do a search on Cassandra database ?
ElasticSearch indexes the data stored in Cassandra.
When you do graph traversals, it uses the search index to retrieve the data from Cassandra. Cheers!
Disclaimer: I am very new to ELK Stack, so this question can be very basic.
I am setting up ELK stack now. I have below basic questions about ElasticSearch.
What is the storage model elastic search is following?
For example Oracle is using relational model ,Alfresco is using "document model" and Apache Jackrabbit is using "hierarchial model"
2.Log data stored in elastic search is persistent/permanent ? Or ElasticSearch deletes log data after certain period?
3.How we will manage/backup this data?
4.Log/data files in Elastic Search is human-readable?
Any help/route to documentation will be appreciated.
the storage model is a Document model. Everything is a document. The documents are of a particular type and they are stored in an index.
Data send to ES is stored on disk. It can be then read, searched or deleted through a REST API.
The Data is managed through the rest API. Usually for log centralisation, the logs are stored in date-based index (one index for today, one for yesterday and so on), so to delete the logs from one day, you delete the relevant index. Curator can help in this case. ES offers a backup and restore module.
To access the data in ES, you'll have to use the REST API or use the Kibana client.
Documentation:
https://www.elastic.co/guide/en/elasticsearch/guide/current/index.html
https://www.elastic.co/guide/en/elasticsearch/reference/current/index.html
I started looking into ElasticSearch, and most examples of creating and reading involve POSTing data to the ElasticSearch server and then doing a GET to retrieve them.
Is this data that is POSTed stored separately by the ElasticSearch server? So, if I want to use ElasticSearch with MongoDB, does the raw data, not including the search indices, get stored twice (once copy for MongoDB and one for ElasticSearch)?
In conjunction with an answer to this question, a description or a link to a description of how ElasticSearch and the primary data store interact would be very helpful.
Yes, ElasticSearch can only search within its own data store, so a separate copy will be there.
You can use the mongodb connector to keep the data in elastic in sync with the mongo database: https://github.com/mongodb-labs/mongo-connector
How are events indexed and stored by Elasticsearch when using ELK (Elastichsearch, Logstash, Kibana)
How does Elasticsearch work in ELK
Looks like you got downvoted for not just reading up at elastic.co, but...
logstash picks up unstructured data from log files and other sources, transforms it into structured data, and inserts it into elasticsearch.
elasticsearch is the document repository. While it's not useful for log information, it's a text engine at heart and can analyze the data (tokenization, stop words, stemming, etc).
kibana reads from elasticsearch and allows you to explore the data and make dashboards.
That's the 30,000-ft overview.
Elasticsearch have the function of database on ELK Stack.
You can read more information about Elasticsearch and ELK Stack here: https://www.elastic.co/guide/en/elasticsearch/guide/current/index.html.
first of all you will have logs file that you used to write system logs on it
for example when you add new record to database you will write the record in any form you need to log file like
date,"name":"system","serial":"1234" .....
after that you will add your configuration in logstash to parse the data from the logs
and it will be like
name : system
.....
and the data will saved in elastic search
kibana is used to preview the elastic search data
and you can use send a request to elasticsearch with the required query and get your data from it