Multi-dialect SQL language support for VS Code, powered by the sqllens analyzer via sqllens-language-server. Fully self-contained: the language server is bundled with the extension, so installing it is the only step.
Source-first and semantics-first: SQL is understood statically, across ten real dialects, without a database connection.
Features
- Diagnostics: positioned syntax errors plus semantic errors (unknown table/column/field) when a schema catalog is configured.
- Typed hover (with nullability where provable), go-to-definition, find references, document highlight, document symbols, code lens.
- Scope-aware completion (works mid-edit), signature help, inlay hints, semantic highlighting, folding and selection ranges.
Dialects: databricks, tsql, snowflake, bigquery, redshift,
postgres, duckdb, trino, sqlite, mysql.
Configuration: .sqllens.json
Optional, at the workspace root. Maps files to dialects (first match wins) and points at a schema catalog that switches on the semantic tier:
{
"dialects": [{ "files": "tsql/**/*.sql", "dialect": "tsql" }],
"default": "duckdb",
"schema": "schema.json"
}
schema.json is a plain { "table": { "column": "type" } } catalog. Without
any config, files fall back to the databricks dialect and the syntax tiers
still work.
No config file at all? The language picker doubles as a dialect picker: set a
file (or a files.associations glob) to "SQL (DuckDB)", "SQL (BigQuery)", ...
and that binds its dialect directly.
Plugins
JavaScript plugins declared in .sqllens.json add live schema catalogs and
custom diagnostics/hover/completion hooks; tutorial in
PLUGINS.md.
Feedback
Issues and suggestions: GitHub issues.
Development
This folder is a self-contained sub-package of the sqllens-language-server repo:
npm install
npm run build # tsc → dist/
npm run package # vsce → .vsix
The bundled server version is pinned by this package's dependency on
sqllens-language-server; extension releases mirror server releases.
License
MIT