Awesome GitHub RepositoriesCustom Aggregation Function Writing

AlaSQL is a JavaScript SQL database engine that allows for the filtering, grouping, and joining of in-memory object arrays and JSON data. It functions as an in-memory SQL database and client-side data processor, enabling the execution of SQL statements against JavaScript arrays and external data sources in both browser and server environments. The project serves as a universal data query tool capable of performing relational joins across diverse sources, such as merging Google Spreadsheets, SQLite files, and remote APIs into a single result set. It also acts as an IndexedDB SQL wrapper, allow

Pinot is a distributed, columnar analytical database designed for high-concurrency, low-latency query processing. It functions as a real-time OLAP datastore, enabling interactive, user-facing analytics by ingesting and querying massive datasets from both streaming and batch sources. The system architecture relies on a centralized controller for cluster coordination and a distributed segment-based storage model to ensure horizontal scalability. The platform distinguishes itself through a hybrid ingestion pipeline that unifies real-time event streams and historical batch data into a single quer

Apache Hive is a SQL-on-Hadoop data warehouse that enables querying and managing petabytes of data stored in distributed storage such as HDFS and cloud storage services. It provides a familiar SQL interface for batch analytics and reporting, supported by a core set of components including the HiveServer2 Thrift service for remote query execution, the Hive Metastore Service for central metadata management, the Hive ACID Transaction Engine for concurrent read-write operations, and the Hive LLAP Interactive Engine for low-latency analytical processing. The WebHCat REST API offers an HTTP interfac

Arroyo is a high-performance stream processing platform built in Rust. It executes continuous SQL queries on streaming data with event-time semantics, enabling accurate windowed aggregations, joins, and stateful computations on unbounded event streams. The platform uses native Rust execution for high throughput and low latency, with periodic checkpointing for exactly-once fault tolerance and horizontal scaling across distributed workers. The system integrates deeply with Kafka for reading and writing topics with exactly-once delivery and supports change data capture (CDC) from MySQL and Postg

H2 是一个用 Java 编写的 JDBC 兼容关系型数据库管理系统。它作为一个可嵌入的 SQL 数据库，可以直接在应用程序进程内运行以消除网络延迟，或者作为内存数据库用于高性能的易失性存储。它还包含一个基于 Web 的控制台，用于执行 SQL 命令和管理模式。 该系统的特点是其灵活的部署模式，包括用于远程 TCP/IP 访问的独立服务器模式，以及用于同时进行本地和远程连接的混合模式。它具有方言模拟层和兼容模式，允许其模仿其他数据库系统的行为和语法。 该引擎提供了一套广泛的功能，涵盖具有多版本并发控制（MVCC）的 ACID 事务、地理空间和 JSON 数据支持，以及高级分析窗口函数。它包括通过压缩备份、SQL 脚本恢复和堆外内存管理来处理大数据集的数据保护工具。 该数据库使用标准的 Java 数据库连接驱动程序和连接 URL 与应用程序集成。

Velox 是一个高性能 C++ 查询执行引擎和列式数据处理库。它作为一个用于实现分析型查询引擎的可组合框架，提供了向量化表达式评估器和数据管理系统工具包。 该项目以使用向量化列式执行和基于 Arena 的内存分配来处理大规模数据集而著称。它具有专门的优化功能，如广播连接表缓存、动态过滤器下推和字典编码，以减少内存开销并加速分析读取。 该引擎涵盖了广泛的分析能力，包括实现哈希连接、合并连接和半连接，以及多阶段并行聚合和窗口函数计算。它提供了用于列式内存存储、Parquet 数据解码以及与云存储集成的原语。 通过用于自定义标量和聚合函数的函数注册系统提供可扩展性，并提供高级绑定以将 C++ 逻辑连接到 Python。