Do you only need the current count or do you want to keep the historical counts also? By active users, does that mean some kind of user that the application tracks (as opposed to the Cassandra user connected to the cluster)?
I would consider a table like this for tracking active users through time: Create table users_by_day ( app_date date, hour integer, minute integer, user_count integer, longest_login_user text, longest_login_seconds integer, last_login datetime, last_login_user text ) primary key (app_date, hour, minute); Then, your reporting can easily select full days or a specific, one-minute slice. Of course, the app would need to have a timer and write out the data. I would also suggest a TTL on the data so that you only keep what you need (a week, a year, whatever). Of course, if your reporting requires different granularities, you could consider a different time bucket for the table (by hour, by week, etc.) Sean Durity – Staff Systems Engineer, Cassandra From: Abdul Patel <abd786...@gmail.com> Sent: Thursday, February 6, 2020 1:54 PM To: user@cassandra.apache.org Subject: [EXTERNAL] Re: Running select against cassandra Its sort of user connected, app team needa number of active users connected say every 1 to 5 mins. The timeout at app end is 120ms. On Thursday, February 6, 2020, Michael Shuler <mich...@pbandjelly.org<mailto:mich...@pbandjelly.org>> wrote: You'll have to be more specific. What is your table schema and what is the SELECT query? What is the normal response time? As a basic guide for your general question, if the query is something sort of irrelevant that should be stored some other way, like a total row count, or most any SELECT that requires ALLOW FILTERING, you're doing it wrong and should re-evaluate your data model. 1 query per minute is a minuscule fraction of the basic capacity of queries per minute that a Cassandra cluster should be able to handle with good data modeling and table-relevant query. All depends on the data model and query. Michael On 2/6/20 12:20 PM, Abdul Patel wrote: Hi, Is it advisable to run select query to fetch every minute to grab data from cassandra for reporting purpose, if no then whats the alternative? --------------------------------------------------------------------- To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org<mailto:user-unsubscr...@cassandra.apache.org> For additional commands, e-mail: user-h...@cassandra.apache.org<mailto:user-h...@cassandra.apache.org> ________________________________ The information in this Internet Email is confidential and may be legally privileged. It is intended solely for the addressee. Access to this Email by anyone else is unauthorized. If you are not the intended recipient, any disclosure, copying, distribution or any action taken or omitted to be taken in reliance on it, is prohibited and may be unlawful. When addressed to our clients any opinions or advice contained in this Email are subject to the terms and conditions expressed in any applicable governing The Home Depot terms of business or client engagement letter. The Home Depot disclaims all responsibility and liability for the accuracy and content of this attachment and for any damages or losses arising from any inaccuracies, errors, viruses, e.g., worms, trojan horses, etc., or other items of a destructive nature, which may be contained in this attachment and shall not be liable for direct, indirect, consequential or special damages in connection with this e-mail message or its attachment.
