Phases 1-3 built the storage primitives — vectors, row groups, column segments, and compression. But there’s no concept of a “table” yet. There’s no way to define a schema (CREATE TABLE), no way...

This lesson should have been learned with the CREATE TABLE of death, but it is worth a refresh. Do not uselessly grant CREATE and ALTER TABLE The reason I am posting this reminder is that...

PostgreSQL 19 Beta has been announced, with general availability expected in September, following the project's yearly major-release cadence. This release introduces native SQL Property Graph...

PostgreSQL's table access method interface lets you plug in alternative storage engines.

Phase 1 gave us pages and heap files (raw byte storage on disk). Phase 2 gave us schemas and serialization (typed values to/from bytes). But these two layers don’t know about each other — you’d...

PostgreSQL's Table Access Method API is finally seeing real action.

When everyone has access to the same AI models, the winners are those who use them to build advantages that competitors can’t copy.

最近，一位客户的数据库表的auto_increment值接近最大容量。为避免超限，建议将数据类型从INT UNSIGNED更改为BIGINT。在使用pt-online-schema-change进行修改时，由于索引过大导致进程缓慢，最终决定取消该操作，采用Aurora蓝绿部署，直接在新集群上进行ALTER操作。通过删除次级索引后再添加，成功在auto_increment耗尽前完成了修改。此案例强调了监控auto_increment和合理规划的重要性。

Here is a GUC that ships with a warning label. The docs, which are normally restrained to the point of parody, state plainly that setting this parameter wrong can cause “irretrievable data loss or...

PDF table extraction often looks easy until it fails in production. Real bank statements can be messy, with scanned pages, shifting layouts, merged cells, and wrapped rows that break standard Java...

Google 的 Swiss Table 是一种高效的哈希表实现，利用 SIMD 指令实现 16 路并行探测，性能比传统的 std::unordered_map 快 2 倍以上。它通过控制字节优化内存访问，减少缓存未命中率，提升查找效率，并采用开放寻址策略，解决了链式哈希的内存开销和性能瓶颈问题。

PostgreSQL 19 增加了 ALTER PUBLICATION 中对 EXCEPT TABLE 的支持，允许用户灵活地修改排除列表，从而更有效地管理表的发布和排除，提升了数据库的灵活性和可控性。

PostgreSQL 19将引入EXCEPT TABLE语法，允许用户在创建出版物时排除一个或多个表，从而避免将这些表的数据发送给订阅者。对于分区表，排除将在根级别应用，未来将支持通过ALTER PUBLICATION管理这些排除项。这一改进将增强逻辑复制的灵活性。

MySQL HeatWave is a fully-managed MySQL database service that combines transactions, analytics, machine learning, and GenAI services, without ETL duplication. Also included is HeatWave Lakehouse,...

文章介绍了《易经》六十四卦的Unicode范围（U+4DC0到U+4DFF），并提供了Python、PowerShell和JavaScript的代码示例，用于输出所有卦象。

2025年12月14日，亚历山大·科罗特科夫提交了ALTER TABLE ... MERGE PARTITIONS ...和ALTER TABLE ... SPLIT PARTITION ...两个DDL命令补丁。这些命令用于合并和拆分分区，但在高负载下不建议用于大型分区表，尽管为未来改进奠定了基础。

Managing large datasets can be a balancing act between performance and storage. Keeping your “hot” data lean is critical for speed and memory efficiency. But what about the “cold” data you still...

© Laurenz Albe 2025 Sometimes a string column should only contain one of a limited number of distinct values. Examples would be the current state of a service request or the US state in an...