# PDU — PostgreSQL Data Unloader

> PDU is a PostgreSQL physical data recovery tool. It reads database files and WAL directly when normal SQL access is unavailable.

PDU can reconstruct offline catalog metadata, export readable heap and TOAST data, recover selected deleted or pre-update rows from available WAL, and scan disk fragments for dropped-table recovery. It is an emergency recovery aid, not a replacement for backups, pgBackRest, or PITR.

## Primary resources

- Product overview: https://pduzc.com/features
- Recovery scenarios: https://pduzc.com/use-cases
- Verified recovery cases: https://pduzc.com/cases
- Documentation: https://pduzc.com/docs
- Quick start: https://pduzc.com/quickstart
- Technical articles: https://pduzc.com/blog
- GitHub: https://github.com/wublabdubdub/PDU-PostgreSQLDataUnloader
- PostgreSQL project announcement: https://www.postgresql.org/about/news/pdu-an-open-source-postgresql-data-unloader-for-full-database-offline-export-and-targeted-wal-recovery-3335/

## 中文说明

PDU 是 PostgreSQL 物理数据恢复工具，可在数据库无法启动时直接读取数据文件和 WAL，用于损坏文件提取、误删/误更新恢复和被删除表的碎片扫描。恢复前应先保护并复制原始 PGDATA。