wasm_browser

tinySQL WASM Browser (wasm_browser)

Part of tinySQL. For the full local-first browser app and GIS editor, see query_files_wasm.

Compiles tinySQL to WebAssembly and serves it with a browser UI. The SQL engine runs client-side; no server is needed after the initial file download.

Build

cd cmd/wasm_browser

# Build only (produces web/tinySQL.wasm, optional .gz, and web/wasm_exec.js)
./build.sh --build-only

# Build and start a local HTTP server on port 8080
./build.sh --serve

# Serve existing assets without rebuilding
./build.sh --skip-build --serve

Then open http://localhost:8080.

Manual equivalent:

cd cmd/wasm_browser
GOOS=js GOARCH=wasm go build -o web/tinySQL.wasm .
cp "$(go env GOROOT)/lib/wasm/wasm_exec.js" web/
cd web && python3 -m http.server 8080

UI features

• SQL editor with multi-statement support
• Result table with column headers
• Schema inspector (list tables, show columns)
• SQL editor state, selected demo query, and the database snapshot are restored from localStorage
• Export results as CSV or JSON
• CRS, WMS axis-order, OGC TileMatrix, WKB/EWKB, and GeoPackageBinary SQL functions from the generated function reference

The browser build excludes the path-based sqliteimport GeoPackage/MBTiles reader. See the geospatial standards guide for supported formats and CRS profiles.

JavaScript API

The module exposes window.tinySQL:

Notes

• The engine runs in memory. The demo persists a compact database snapshot to localStorage after successful mutations and restores it on reload. Clear the browser's site data for the demo origin to reset it.
• WASM files must be served over HTTP (not file://) due to browser security restrictions — use the built-in server or any static file host.
• Modern browsers load the generated tinySQL.wasm.gz companion and stream it through DecompressionStream; older browsers and hosts that already apply compression fall back to tinySQL.wasm automatically.
• The browser API executes directly against tinySQL's engine instead of through database/sql; this reduces bundle size and avoids connection-pool overhead.
• Repeated SQL text is served from a bounded compile cache, avoiding parser work on hot query paths.
• Set window.tinySQLWasmDebug = true before loading the module to enable diagnostic console logs; normal query paths stay quiet.
• For a Node.js variant see ../wasm_node/.

Performance benchmark

Run the repeat-query benchmark against a built browser module:

node wasm_benchmark.js web/tinySQL.wasm 10000

The output reports elapsed time, throughput, and microseconds per query or update as JSON. Pass another WASM file as the first argument to compare builds.