SQLFluff Extension for VS Code

A VS Code extension for SQLFluff, a SQL linter and formatter. SQLFluff is a popular, dialect-aware SQL linter and formatter that helps you write clean, consistent SQL code.

This extension fully relies on the SQLFLuff linter and formatter. It simply provides very barebones integration into VS Code via the Language Server Protocol (LSP).

Features

• SQL Linting: Checks your SQL code for syntax errors, style issues, and best practices
• SQL Formatting: Automatically formats your SQL code using sqlfluff fix which respects your project configuration
• Multiple SQL Dialects: Supports various SQL dialects like PostgreSQL, MySQL, BigQuery, Snowflake and more
• Format on Save: Optional ability to format your SQL code whenever you save
• Configurable Rules: Enable or disable specific linting rules to match your team's coding standards via .sqlfluff or pyproject.toml files

Requirements

• Python 3.8 or above
• VS Code 1.64.0 or above
• Python extension for VS Code

Extension Settings

This extension contributes the following settings:

• sqlfluff.args: Additional arguments passed to SQLFluff
• sqlfluff.path: Path to SQLFluff binary if not using the bundled version
• sqlfluff.importStrategy: Controls where SQLFluff is imported from ("useBundled" or "fromEnvironment")
• sqlfluff.interpreter: Python interpreter to use for SQLFluff
• sqlfluff.showNotifications: Controls when notifications are shown
• sqlfluff.diagnosticSeverity: Controls the severity level of SQLFluff diagnostics (error, warning, information, hint)
• sqlfluff.dialect: Specifies which SQL dialect to use for linting and formatting
• sqlfluff.templater: Defines which templater to use for processing SQL files

Note: While SQLFluff configurations are typically defined in .sqlfluff or pyproject.toml files, the VS Code settings above will override those configurations if set. This allows you to customize SQLFluff behavior specifically within VS Code without changing your project-level configurations.

SQLFluff Commands

The extension provides the following commands (accessible via Command Palette):

• SQLFluff: Restart Server (sqlfluff.restart): Restarts the language server

Configuration

SQLFluff can be configured using a .sqlfluff configuration file or pyproject.toml file in your project root. The extension will respect these project-level configurations when linting and formatting SQL files.

Example .sqlfluff configuration:

[sqlfluff]
dialect = snowflake
templater = jinja
exclude_rules = L016

[sqlfluff:indentation]
indented_joins = True
indented_using_on = True

[sqlfluff:layout:type:comma]
line_position = trailing

[sqlfluff:rules]
allow_scalar = True
unquoted_identifiers_policy = all

[sqlfluff:rules:capitalisation.keywords]  # CP01, formerly L010
capitalisation_policy = upper

[sqlfluff:rules:capitalisation.functions]  # CP03, formerly L030
capitalisation_policy = upper

Example pyproject.toml configuration:

[tool.sqlfluff]
dialect = "snowflake"
templater = "jinja"
exclude_rules = ["L016"]

[tool.sqlfluff.indentation]
indented_joins = true
indented_using_on = true

[tool.sqlfluff.layout.type.comma]
line_position = "trailing"

[tool.sqlfluff.rules]
allow_scalar = true
unquoted_identifiers_policy = "all"

[tool.sqlfluff.rules.capitalisation.keywords]  # CP01, formerly L010
capitalisation_policy = "upper"

[tool.sqlfluff.rules.capitalisation.functions]  # CP03, formerly L030
capitalisation_policy = "upper"

For detailed configuration options, see SQLFluff documentation.

Supported SQL Dialects

• ANSI (default)
• BigQuery
• ClickHouse
• Databricks
• DB2
• DuckDB
• Hive
• MySQL
• Oracle
• PostgreSQL
• Redshift
• Snowflake
• SparkSQL
• SQLite
• Teradata
• TSQL (SQL Server)

Quick Start

1. Install the extension
2. Open a SQL file (.sql extension)
3. Errors and warnings will be highlighted automatically
4. Format document with Format Document command (Shift+Alt+F) or on save if enabled

Troubleshooting

• SQLFluff Not Found: Make sure Python is installed and available in your path
• No Linting Results: Check if you have the correct dialect selected for your SQL
• Formatting Issues: Try using the dedicated "SQLFluff: Format SQL" command which uses sqlfluff fix internally
• Configuration Not Applied: Ensure your .sqlfluff or pyproject.toml file is correctly formatted and in the project root
• Performance Issues: For large files, consider excluding some rules in your configuration

Release Notes

1.0.0

Initial release of SQLFluff extension for VS Code

Development

Building the Extension

npm install
npm run package

Running Tests

npm test

License

This extension is licensed under the MIT License.