SQL Server driver

From built-in to plugin

The first two phases of SQL Server support were built as a built-in driver on the feat/sql-server branch of the app repository (epic #150): read-only connect, schema browsing and paginated SELECT queries, followed by TLS/auth connection fields and a TDS backend evaluation. That work proved the driver out — and also showed that the plugin path had caught up with what SQL Server needs.

The direction has changed: SQL Server now ships as a driver plugin, developed in tabularis-sqlserver-plugin. What tipped the decision:

• Independent release cadence. A driver plugin ships fixes and features on its own schedule instead of waiting for the next app release — the same channel Oracle, LibSQL and the other community drivers use.
• Leaner core binary. The TDS stack (tiberius + deadpool + TLS plumbing) stays out of the app binary that every user downloads, SQL Server user or not.
• The plugin protocol grew up. Capability flags, batch schema snapshots for the ER diagram, and execution-plan rendering are all expressible over the JSON-RPC plugin interface today — the gaps that originally justified a built-in are closed.

The built-in work was not thrown away: the introspection queries, pagination dialect, type-extraction rules and test discipline from feat/sql-server carried over into the plugin.

What the plugin covers

The plugin is written in Rust on top of tiberius with deadpool connection pooling, speaking JSON-RPC 2.0 over stdio like every other Tabularis driver plugin. The feature surface being built:

• Connections — pooled connections with session reset (sp_reset_connection), per-connection startup scripts, and TLS via the standard Tabularis ssl_mode values mapped onto the TDS encryption policy (disable, prefer, require, verify-full against the system trust store)
• Introspection — schemas, tables, columns, primary/foreign keys, indexes, views, routines and triggers
• Queries — execution with pagination, CTE/DML classification, multiple result sets, session-preserving batches, and accurate affected-row counts including DML OUTPUT
• Writes — INSERT / UPDATE / DELETE with composite primary keys and safe IDENTITY_INSERT recovery
• DDL — table, view, index and foreign-key DDL plus safe ALTER COLUMN generation; trigger create/edit/remove; procedure and function management with typed OUT/INOUT variables
• Explain — static and runtime execution plans via SHOWPLAN_XML / STATISTICS XML, rendered in the app's Visual EXPLAIN
• Types — the full common SQL Server type set, including DATETIMEOFFSET, UNIQUEIDENTIFIER, XML, SQL_VARIANT, ROWVERSION, HIERARCHYID and spatial types; BIGINT values outside JavaScript's safe range are delivered as strings

Targets: Linux x64/arm64, macOS x64/arm64, Windows x64.

What's still open

The plugin is in development — there is no release yet and it is not in the plugin registry. Known limitations being worked through:

• SQL authentication only; Azure AD and Windows Integrated Authentication are follow-up work
• Primary-key membership changes are disabled: the single-column alteration API cannot safely preserve composite PKs and referencing foreign keys
• Custom CA files and client certificates are rejected; strict TLS verification uses the system trust store

Once the first release lands, installation will be Settings → Plugins in Tabularis, or a manual download from the repository's releases page.

Try it and contribute

Start a throwaway SQL Server 2022 (~1.5 GB image, pulls once):

docker run -e 'ACCEPT_EULA=Y' \
  -e 'MSSQL_SA_PASSWORD=Strong!Pass123' \
  -p 1433:1433 \
  mcr.microsoft.com/mssql/server:2022-latest

Then build the plugin from source and install it locally:

git clone https://github.com/TabularisDB/tabularis-sqlserver-plugin.git
cd tabularis-sqlserver-plugin
just dev-install   # build + copy binary and manifest into the Tabularis plugins dir

Restart Tabularis and add a connection — driver SQL Server, host localhost, port 1433, user sa, password Strong!Pass123, database master.

Issues, testing reports and PRs all go to tabularis-sqlserver-plugin — not the app repository. Comment on an issue before starting so two people don't land on the same task.