This repository is the Chinese translation of the PostgreSQL documentation, maintained by the PostgreSQL China User Group. It contains translated SGML and XML files for PostgreSQL versions 15 through 18, along with vendored DocBook DSSSL stylesheets (v1.79) and DTDs for rendering. The translation uses a custom marker system (`pgdoc-cn_start`/`pgdoc-cn_end`) with checksums to track original English content and translation state. A set of Python scripts (in `tools/`) post-processes the output, adding navigation bars, edit links, and generating mapping files. The project is actively maintained, but the toolchain is legacy (DocBook DSSSL from 2003, Python 3.4 references) and the duplicated version directories create maintenance overhead. This is not a standalone application or data pipeline; it is a documentation localization project with build tooling. Hybrid nature: primarily translation content, secondarily documentation processing scripts.