---
title: 'This Week in Databend #136'
date: 2024-03-18
slug: category-weekly/2024-03-18-databend-weekly
cover_url: 'weekly/weekly-136.jpg'
image: 'weekly/weekly-136.jpg'
tags: [weekly]
category: Weekly
description: 'Stay up to date with the latest weekly developments on Databend!'
contributors:
  - name: andylokandy
  - name: ariesdevil
  - name: b41sh
  - name: BohuTANG
  - name: chienguo
  - name: dantengsky
  - name: Dousir9
  - name: drmingdrmer
  - name: everpcpc
  - name: Freejww
  - name: JackTan25
  - name: ncuwaln
  - name: PsiACE
  - name: SkyFan2002
  - name: soyeric128
  - name: suimenno3002
  - name: sundy-li
  - name: TCeason
  - name: TracyZYJ
  - name: xudong963
  - name: youngsofun
  - name: zhang2014
  - name: ZhiHanZ
  - name: zhyass
authors:
  - PsiACE
---

[Databend](https://github.com/databendlabs/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](https://app.databend.com) .

## What's New

Stay informed about the latest features of Databend.

### Understanding Tasks and Notifications in Databend

Databend now supports a comprehensive mechanism for tasks and notifications.

Tasks are executed according to a schedule or based on a DAG of tasks, executing specified SQL statements. With notification integrations, notifications can be sent to external messaging services.

{/* truncate */}

```sql
CREATE TASK IF NOT EXISTS mytask
 WAREHOUSE = 'mywh'
 SCHEDULE = 30 SECOND
 ERROR_INTEGRATION = 'myerror'
AS
BEGIN
    BEGIN;
    INSERT INTO mytable(ts) VALUES(CURRENT_TIMESTAMP);
    DELETE FROM mytable WHERE ts < DATEADD(MINUTE, -5, CURRENT_TIMESTAMP());
    COMMIT;
END;
```

The above example defines a task named mytask that runs every 30 seconds on the mywh compute cluster. The task executes a multi-statement transaction that includes an `INSERT` statement and a `DELETE` statement. When the task fails, it will trigger an error integration named `myerror`.

The mechanisms related to tasks and notifications are ready to use out of the box in Databend Cloud. If you would like to learn more, please contact the [Databend team](https://databend.com/contact-us/) or refer to the resources listed below:

- [Docs | Task ](https://docs.databend.com/sql/sql-commands/ddl/task/)
- [Docs | Notification ](https://docs.databend.com/sql/sql-commands/ddl/notification/)

## Code Corner

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

### Databend vs. Snowflake: Data Ingestion Benchmark

We conducted four specific benchmarks to evaluate Databend Cloud versus Snowflake:

- **TPC-H SF100 Dataset Loading:** Focuses on loading performance and cost for a large-scale dataset (100GB, ~600 million rows).
- **ClickBench Hits Dataset Loading:** Tests efficiency in loading a wide-table dataset (76GB, ~100 million rows, 105 columns), emphasizing challenges associated with high column counts.
- **1-Second Freshness:** Measures the platforms' ability to ingest data within a strict 1-second freshness requirement.
- **5-Second Freshness:** Compares the platforms' data ingestion capabilities under a 5-second freshness constraint.

#### Data Loading Benchmark

![data loading](../static/img/blog/databend-vs-snowflake-data-loading.png)

#### Freshness Benchmark

![data freshness](../static/img/blog/databend-vs-snowflake-data-freshness.png)

Welcome to read the following documentation to understand the low-cost, high-performance data ingestion of Databend Cloud.

- [Docs | Databend vs. Snowflake: Data Ingestion Benchmark](https://docs.databend.com/guides/benchmark/data-ingest)

## Highlights

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

- Added support for spill in `CROSS JOIN`.
- Added support for spill in the new aggregate hash table.
- Added support for refreshing inverted indexes.
- Added more function aliases for time and date related functions to support more data analysis tools.

## 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.

### Adding support for TOP K Syntax

Databend plans to support the `SELECT TOP` statement to pick the top K items from a result set.

The following `SELECT TOP` statement is used to select the top 4 items from an ordered result set:

```sql
select TOP 4 c1 from testable ORDER BY c1;
```

Equivalent to the following `SELECT ... LIMIT` statement.

```sql
select c1 from testable order by c1 limit 4;
```

This is a good first issue, aimed at guiding everyone interested in Rust and Databend to participate.

[Issue #14972 | Feature: top k syntax support](https://github.com/databendlabs/databend/issues/14972)

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](https://link.databend.com/i-m-feeling-lucky) to get started.

## New Contributors

We always open arms to everyone and can't wait to see how you'll help our community grow and thrive.

- [@suimenno3002](https://github.com/suimenno3002) implemented support for histogram aggregate functions, [#14839](https://github.com/databendlabs/databend/pull/14839).

## Changelog

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

**Full Changelog**: [https://github.com/databendlabs/databend/compare/v1.2.371-nightly...v1.2.378-nightly](https://github.com/databendlabs/databend/compare/v1.2.371-nightly...v1.2.378-nightly)