OpenADS — Documentation (English)

OpenADS is a free, clean-room implementation of an ADS-compatible database engine. It is a drop-in replacement for the Advantage Client Engine (ace32.dll / ace64.dll / libace.so) — Harbour / Clipper applications that link against contrib/rddads keep working without recompilation.

Current release: v1.0.0-rc29.

What’s in here

• Getting started — install, first build, smoke test.
• Architecture — five-layer architecture (ABI / Session / SQL / Engine / Platform).
• Wire protocol — formal spec of the OpenADS-native TCP / TLS wire (frame layout, every opcode, payload format, error semantics, versioning).
• Main flows — interactive single-page sequence walk-through of the eight canonical call paths (local DBF, remote TCP, SQL pipeline, Studio HTTP, AOF/Rushmore, memo I/O, transactions, wire-protocol opcodes), backed by assets/flows.json.
• Data Dictionary — clean-room .add text format + the engine::DataDict API + REST surface.
• Studio (web console) — administer an OpenADS database from any browser through the embedded HTTP console (Remote Server or LocalServer mode).
• Benchmarks — cross-platform SQL workload numbers + AOF (Rushmore) + wire-protocol xbrowse repaint.
• rddads / X# RDD compat — Harbour contrib/rddads and X# AXDBFCDX compatibility surface (rc19 M12.22 / M12.23).
• Service deployment — run openads_serverd as a Windows Service / systemd unit / macOS launchd plist (rc14).
• TLS deployment — terminate HTTPS in front of Studio with Caddy / nginx / stunnel / SSH tunnel.
• Ordinal compatibility — fix the Windows “ordinal NNN not found” loader error when an app’s import table references SAP-style ordinals.
• Known issues — current open items.

Other languages

Español · Português

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Table of contents

• Getting started
• Architecture
• Studio (web console)
• Wire protocol
• Benchmarks
• Data Dictionary
• rddads / X# RDD compat
• TLS deployment
• Fix "ordinal NNN not found"
• Service deployment
• Main flows