Redpanda and ClickHouse

Presented on December ClickHouse Meetup. Dec 3, 2019 Concrete findings and "best practices" from building a cluster sized for 150 analytic queries per second on 100TB of http logs. Topics covered: hardware, clients (http vs native), partitioning, indexing, SELECT vs INSERT performance, replication, sharding, quotas, and benchmarking.

ClickHouse clusters depend on ZooKeeper to handle replication and distributed DDL commands. In this Altinity webinar, we’ll explain why ZooKeeper is necessary, how it works, and introduce the new built-in replacement named ClickHouse Keeper. You’ll learn practical tips to care for ZooKeeper in sickness and health. You’ll also learn how/when to use ClickHouse Keeper. We will share our recommendations for keeping that happy as well.

JSON is the king of data formats and ClickHouse has a plethora of features to handle it. This webinar covers JSON features from A to Z starting with traditional ways to load and represent JSON data in ClickHouse. Next, we’ll jump into the JSON data type: how it works, how to query data from it, and what works and doesn’t work. JSON data type is one of the most awaited features in the 2022 ClickHouse roadmap, so you won’t want to miss out. Finally, we’ll talk about Jedi master techniques like adding bloom filter indexing on JSON data.

This presentation covers all aspects of PostgreSQL administration, including installation, security, file structure, configuration, reporting, backup, daily maintenance, monitoring activity, disk space computations, and disaster recovery. It shows how to control host connectivity, configure the server, find the query being run by each session, and find the disk space used by each database.

An instant world requires instant decisions at scale. This includes the ability to digest and react to changes in real-time. Thus, event logs such as Apache Kafka can be found in almost every architecture, while databases and similar systems still provide the foundation. Change Data Capture (CDC) has become popular for propagating changes. Nevertheless, integrating all these systems, which often have slightly different semantics, can be a challenge. In this talk, we highlight what it means for Apache Flink to be a general data processor that acts as a data integration hub. Looking under the hood, we demonstrate Flink's SQL engine as a changelog processor that ships with an ecosystem tailored to processing CDC data and maintaining materialized views. We will discuss the semantics of different data sources and how to perform joins or stream enrichment between them. This talk illustrates how Flink can be used with systems such as Kafka (for upsert logging), Debezium, JDBC, and others.

This document discusses building event streaming architectures using Scylla and Confluent Kafka. It provides an overview of Scylla and how it can be used with Kafka at Numberly. It then discusses change data capture (CDC) in Scylla and how to stream data from Scylla to Kafka using Kafka Connect and the Scylla source connector. The Kafka Connect framework and connectors allow capturing changes from Scylla tables in Kafka topics to power downstream applications and tasks.

Joins in Kafka Streams and ksqlDB are a killer-feature for data processing and basic join semantics are well understood. However, in a streaming world records are associated with timestamps that impact the semantics of joins: welcome to the fabulous world of _temporal_ join semantics. For joins, timestamps are as important as the actual data and it is important to understand how they impact the join result. In this talk we want to deep dive on the different types of joins, with a focus of their temporal aspect. Furthermore, we relate the individual join operators to the overall ""time engine"" of the Kafka Streams query runtime and explain its relationship to operator semantics. To allow developers to apply their knowledge on temporal join semantics, we provide best practices, tip and tricks to ""bend"" time, and configuration advice to get the desired join results. Last, we give an overview of recent, and an outlook to future, development that improves joins even further.

From webinar on December 3, 2019 New users of ClickHouse love the speed but may run into a few surprises when designing applications. Column storage turns classic SQL design precepts on their heads. This talk shares our favorite tricks for building great applications. We'll talk about fact tables and dimensions, materialized views, codecs, arrays, and skip indexes, to name a few of our favorites. We'll show examples of each and also reserve time to handle questions. Join us to take your next step to ClickHouse guruhood! Speaker Bio: Robert Hodges is CEO of Altinity, which offers enterprise support for ClickHouse. He has over three decades of experience in data management spanning 20 different DBMS types. ClickHouse is his current favorite. ;)

Welcome to a live session of our popular introduction to ClickHouse application development. The talk explains what ClickHouse is and how to install it. We then work through the basics of inserting and selecting data, followed by tips on how to maximize the legendary performance of ClickHouse. You’ll get everything you need to get started on your own application, including some time at the end for questions.