Ctrip DAL: An Open-Source Database Access Framework for Scalable Enterprise Applications

As enterprises grow, database development evolves from single‑team, single‑instance setups to multi‑team, clustered, multi‑database environments, bringing challenges such as scaling, access management, investment protection, and security.

Ctrip, a leading online travel company, addressed these challenges by creating Ctrip DAL, a proprietary database access layer that supports sharding, works with Java and C#, and is compatible with MySQL and SQL Server.

The framework consists of a code generator and a client library; the generator produces standard DAO code or custom method‑level access, while the client is added via Maven dependencies.

By deploying the generator, Ctrip can centrally manage DAL development teams, define database ownership, and enforce consistent access patterns, dramatically improving efficiency, code quality, and maintainability.

Ctrip DAL offers extensive extension points for data source management, mapping, connection string handling, and custom access, and includes built‑in monitoring, logging, and statistics modules.

Developed over three years by Ctrip’s framework team, the DAL now serves over 117 independent teams, more than 2,000 applications, and covers over 90% of Ctrip’s database workloads.

The open‑source release includes the code generator and Java client (with a C# client forthcoming), complete documentation, and ready‑to‑use installation instructions.

For more details, see the GitHub repository: https://github.com/ctripcorp/dal .