This Week in Databend #79

February 1, 2023 · 3 min read

PsiACE

Databend is a powerful cloud data warehouse. Built for elasticity and efficiency. Free and open. Also available in the cloud: .

Databend is a powerful cloud data warehouse. Built for elasticity and efficiency. Free and open. Also available in the cloud: https://app.databend.com .

What's New

Check out what we've done this week to make Databend even better for you.

Features & Improvements ✨

AST

add syntax about parsing presign options with content type (#9771)

Format

add TSV file format back (#9732)

Functions

support array functions prepend and append (#9844)
support array concat (#9804)

Query

add topn runtime filter in native storage format (#9738)
enable hashtable state pass from partial to final (#9809)

Storage

add pruning stats to EXPLAIN (#9724)
cache bloom index object (#9712)

Code Refactoring 🎉

'select from stage' use ParquetTable (#9801)

Meta

expose a single "kvapi" as public interface (#9791)
do not remove the last node from a cluster (#9781)

AST/Expression/Planner

unify Span and Result (#9713)

Executor

merge simple pipe and resize pipe (#9782)

Bug Fixes 🔧

Base

fix not linux and macos jemalloc fallback to std (#9786)

Config

fix table_meta_cache can't be disabled (#9767)

Meta

when import data to meta-service dir, the specified "id" has to be one of the "initial_cluster" (#9755)

Query

fix and refactor aggregator (#9748)
fix memory leak for data port (#9762)
fix panic when cast jsonb to string (#9813)

Storage

fix up max_file_size may oom (#9740)

What's On In Databend

Stay connected with the latest news about Databend.

DML Command - UPDATE

Modifies rows in a table with new values.

Note: Databend guarantees data integrity. In Databend, Insert, Update, and Delete operations are guaranteed to be atomic, which means that all data in the operation must succeed or all must fail.

Syntax

UPDATE <table_name>
SET <col_name> = <value> [ , <col_name> = <value> , ... ]
    [ FROM <table_name> ]
    [ WHERE <condition> ]

Learn More

Docs | DML Command - UPDATE

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.

Support Arrow Flight SQL Protocol

Currently Databend supports the MySQL protocol, and it would be great if Databend could support the Arrow Flight SQL protocol as well.

Typically a lakehouse stores data in parquet files using the MySQL protocol while Databend has to do deserialization from parquet to arrow and then back to MySQL data types. Again on the caller end users use data frames or MySQL result iterators, which also requires serialization of types. With Arrow Flight SQL all of these back and forth serialization costs can be avoided.

Issue 9832: Feature: Support Arrow Flight SQL protocol

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