Databend is an open source elastic and reliable Modern Cloud Data Warehouse, it offers blazing fast query and combines elasticity, simplicity, low cost of the cloud, built to make the Data Cloud easy.
Below is a list of some major changes that we don't want you to miss.
Migrate to new planner
- support limit for new planner (#5301)
- enhance GROUP BY semantic check (#5431)
- avoid ub and delete unnecessary unsafe (#5338)
- fix get function unnecessary double column loop (#5349)
- display friendly error if not started with valid flags (#5443)
Build / Testing / CI
- Sql logic test framework (#5416)
- fix some cases in aggregator plan (#5307)
- fix wrong result of memory table engine (#5364)
- fix server hang when processor panic (#5394)
Let's learn a weekly tip from Databend.
Analyze User Retention With Databend
User retention helps you analyze how many users return to your product or service. Let's go through an example and see how to analyze it in Databend.
Create a Table
CREATE TABLE events(`user_id` INT, `login_date` DATE);
Now we have a table with the following fields:
user_id- a unique identifier for user
login_date- user login date
User Retention Analysis
It's easy and performance to use Databend Retention Function to do the user retention analysis.
SELECT sum(r) AS r1, sum(r) AS r2, sum(r) AS r3 FROM ( SELECT user_id, retention(login_date = '2022-05-15', login_date = '2022-05-16', login_date = '2022-05-17') AS r FROM events GROUP BY user_id );
- How to Analyze User Retention With Databend
- Databend Retention Function
- Support aggregate function
You can check the changelogs of Databend nightly to learn about our latest developments.
Thanks a lot to the contributors for their excellent work this week.
Please join the DatafuseLabs Community if you are interested in Databend.
We are looking forward to seeing you try our code. We have a strong team behind you to ensure a smooth experience in trying our code for your projects. If you are a hacker passionate about database internals, feel free to play with our code.
You can submit issues for any problems you find. We also highly appreciate any of your pull requests.