Elastic search for time series

Hi All,

I am new to Nosql and Elastic Search world.

I am evaluating Database for keeping 5 years of time series data for multiple clients, the data changes from client to client that’s why I am looking for NoSql Database like Elastic Search.

The data is mostly float numbers and we will be crushing numbers quite a lot to get the reporting. We keep data day by day and We need to crunch data of 2 years in a single go.

We have tried using CosmosDB from Microsoft and there are limitations on how much we can do with it and there is no proper aggregation in the Cosmos. I have read about Elastic Search would love to know in detail how the sql query does aggregations perform ?
Is the index performance if we add a new column in the document for a year or two, does it affect the performance while the index is being created in the background ?

I also read about approximations that’s done across shard, the reports generated will require exact values, not approximates, does it causes a significant difference if I turn off approximation (somehow) ?

Thanks in Advance

That is a very broad question, which will be difficult to answer.

Have you looked at the following resources?