ZhaoYongChun

PostgreSQL's pgvector extension enables vector storage and similarity search, but Java lacked a clean mapping. dbVisitor 6.7.0's PgVectorTypeHandler maps vector columns directly to List with full Fluent API support for CRUD and KNN queries.

Dynamic SQL can be expressed with XML tags or written directly in SQL using dbVisitor rules. Both approaches require clear semantics for condition activation, parameter binding, and empty collections. This article covers common rule patterns and explains which forms are not interchangeable.

As dbVisitor expanded from RDBMS to NoSQL, the dialect system's abstractions became fragmented. This post explains a deep architectural refactoring that unifies dialect metadata and command building into a cohesive design — no functional changes, pure structural improvement.

dbVisitor's "Two-Layer Adapter" unifies RDBMS and NoSQL access through two abstractions: Layer 1 — a unified API (LambdaTemplate / Mapper) hiding syntax differences; Layer 2 — JDBC-compliant drivers wrapping NoSQL protocols. Use the full stack, or integrate the driver with an existing MyBatis project after checking its required JDBC capabilities.

After dbVisitor can a single API truly unify RDBMS and NoSQL? This post tackles the controversy and explains the design principles behind dbVisitor's "One API, Access Multiple Databases" vision.

Data storage has diversified beyond RDBMS to NoSQL, NewSQL, and AI Vector. dbVisitor aims to define the next-generation standard: One API, Access Multiple Databases.

In hybrid projects with both MySQL and ElasticSearch, the data access layer often splits between MyBatis XML and complex DSL builders. dbVisitor lets you operate ElasticSearch using the same Mapper interfaces and XML, unifying your data access code.

In hybrid projects with both MySQL and MongoDB, the data access layer often feels fragmented — MyBatis Mapper on one side, MongoTemplate on the other. dbVisitor lets you operate MongoDB using the same Mapper interfaces and XML, achieving a unified architecture.

Java ORM tools are mature for RDBMS, but MongoDB's document model needs ODM (Object-Document Mapping) for clean Java integration. This post surveys the landscape and introduces dbVisitor as a JDBC-based solution.

Use dbVisitor's AND/OR rules to build complex nested SQL conditions in one line.