This Week in Databend #114

Databend is a modern cloud data warehouse, serving your massive-scale analytics needs at low cost and complexity. Open source alternative to Snowflake. Also available in the cloud: https://app.databend.com .

What's On In Databend

Stay connected with the latest news about Databend.

MERGE

The

MERGE

INSERT

UPDATE

DELETE

A

MERGE

MATCHED

NOT MATCHED

MATCHED

UPDATE

DELETE

NOT MATCHED

INSERT

-- Merge data into 'salaries' based on employee details from 'employees'
MERGE INTO salaries
USING (SELECT * FROM employees)
ON salaries.employee_id = employees.employee_id
WHEN MATCHED AND employees.department = 'HR' THEN
    UPDATE SET
        salaries.salary = salaries.salary + 1000.00
WHEN MATCHED THEN
    UPDATE SET
        salaries.salary = salaries.salary + 500.00
WHEN NOT MATCHED THEN
    INSERT (employee_id, salary)
    VALUES (employees.employee_id, 55000.00);

MERGE

is currently in an experimental state. Before using the

MERGE

command, you need to run

SET enable_experimental_merge_into = 1;

to enable the feature.

If you are interested in learning more, please check out the resources below:

• Docs | MERGE

Code Corner

Discover some fascinating code snippets or projects that showcase our work or learning journey.

Introducing

DATABEND_DATA_PATH

to Python Binding and Local Mode

Databend's local mode now allows users to control the storage location of metadata and data files by setting the

DATABEND_DATA_PATH

DATABEND_DATA_PATH=/tmp/data/ databend-query local -q "create table abc(a int); insert into abc values(3);"

DATABEND_DATA_PATH

databend

import os

os.environ["DATABEND_DATA_PATH"] = "/tmp/def/"

from databend import SessionContext

If you are interested in learning more, please check out the resources below:

• PR #13089 | feat: support DATABEND_DATA_PATH in bendpy and databend-local

Highlights

We have also made these improvements to Databend that we hope you will find helpful:

• Improved Hash Join, resulting in a 10% performance improvement in certain scenarios.
• Enhanced distributed execution of MERGE.
• Improved CI by using

  quickinstall
  
  to install relevant binary tools and executing unit tests with

  nextest
  
  .

What's Up Next

We're always open to cutting-edge technologies and innovative ideas. You're more than welcome to join the community and bring them to Databend.

Delete Files When Dropping Internal Stage

In Databend, an Internal Stage stores data files in the storage backend specified in

databend-query.toml

Considering that users will not be able to access the staged files after dropping an Internal Stage, it is necessary to remove the staged files when dropping the Internal Stage.

Issue #12986 | remove files at the same time of drop internal stage

Please let us know if you're interested in contributing to this feature, or pick up a good first issue at https://link.databend.com/i-m-feeling-lucky to get started.

Changelog

You can check the changelog of Databend Nightly for details about our latest developments.

Full Changelog: https://github.com/datafuselabs/databend/compare/v1.2.137-nightly...v1.2.147-nightly