Inline SQL Toolkit

Inline SQL Toolkit highlights SQL embedded in Python strings and formats selected SQL with the bundled sql-formatter layout engine. It supports ordinary .py files, marimo (.mo.py) programs, and Python cells in Jupyter notebooks. In marimo notebooks the python and mo-python cell languages are supported. SQL-language cells and notebook magic commands (%sql, %%sql, and similar magic syntax) are not supported.

Requirements are VS Code 1.95 or newer. Formatting is manual-only: this extension does not register a formatter provider, format on save, format on type, or format ranges automatically. It never executes SQL, validates SQL, infers a SQL dialect, connects to a database, or sends source to the network. The formatter is best-effort; an unsafe candidate is skipped while other safe candidates may still be edited.

In short, SQL is never executed by this extension. SQL is never validated by this extension.

Quick start

Open a supported Python document or notebook cell, place the cursor in one of the examples below, and choose a command from the Command Palette.

Plain string

query = "SELECT id, name FROM users WHERE active = true"

Marker triple-quoted string

query = """
-- sql
select id, name
from users
where active = true
"""

Complex f-string

account_id = get_account_id()
query = f"""
-- sql
SELECT id, name
FROM users
WHERE account_id = {account_id}
  AND status = {{'active'}}
"""

The f-string example demonstrates that Python replacement fields and escaped braces remain Python source. Only the SQL portions are considered for layout; the extension preserves the original f-string expressions and escapes.

Commands

The command IDs are shown for keybindings and automation integrations:

• Inline SQL: Format at Cursor (inlineSql.formatAtCursor) formats the SQL candidate containing the cursor.
• Inline SQL: Format Selection (inlineSql.formatSelection) formats SQL candidates intersecting the current selection.
• Inline SQL: Format All (inlineSql.formatAll) formats every detected candidate in the current document or notebook cell.

Each invocation checks the document version and the expected source text before creating one WorkspaceEdit, so the operation is one undo step. VS Code does not provide an atomic, versioned precondition for an edit that happens after that check. Changes observed before the edit are rejected as stale; a change that races after the check can still be applied because VS Code provides no later atomic precondition.

Settings

• inlineSql.format.keywordCase: upper (default), lower, or preserve.
• inlineSql.format.indentWidth: SQL indentation width from 1 to 8 spaces (default 2).
• inlineSql.format.wrapAfter: preferred line width from 20 to 500 (default 88).
• inlineSql.format.useSpaceAroundOperators: add spaces around operators (default true).
• inlineSql.format.expandSelectList: place every SELECT column on its own indented line in triple-quoted SQL (default true).
• inlineSql.format.trimBlankBoundaries: collapse extra blank lines at the start and end of triple-quoted SQL to a single line ending (default true).
• inlineSql.format.dialect: SQL dialect used by the formatter (sql, mysql, postgresql, or sqlite; default postgresql).

The extension contributes semantic tokens for both the Python code and the SQL it embeds, registered after the Python language server activates. SQL tokens are applied on top of the Python tokens so SQL highlighting is not overwritten by the language server; editor.semanticHighlighting.enabled stays on.

Detection and supported syntax

Formatter detection is source-level: it examines Python tokens and the literal characters in the source, rather than evaluating the string value. A candidate is found when either condition holds:

1. The first logical, non-blank line starts with -- sql or --sql after horizontal whitespace. Matching is case-insensitive and the marker text is preserved.
2. After removing only physically present ASCII space, tab, CR, and LF characters, the source starts with one of SELECT, WITH, INSERT, UPDATE, DELETE, MERGE, CREATE, ALTER, DROP, TRUNCATE, or EXPLAIN, followed by a word boundary. The two source characters \n are not treated as whitespace.

Standalone plain and raw strings, f-strings, and raw f-strings (f, rf, and fr, in either case) are supported with single, double, and triple delimiters (', ", ''', and """). A parseable candidate in a supported literal is also the candidate used by the syntax highlighting grammar.

The following are intentionally skipped: bytes and byte strings (b/rb), implicit or explicit string concatenation, t-strings, invalid Python, dynamic or non-literal SQL, and SQL-language cells. A candidate that cannot be restored without changing Python source is reported as unsafe and is not edited.

Trust, privacy, and offline behavior

In an untrusted workspace the extension provides highlighting only. The three formatting commands remain visible, but formatting is disabled: no analysis runs, no Code Actions are offered, and no edits are applied until the workspace is trusted. SQL is not written to disk, logged, telemetered, sent over the network, passed to a shell/database, or executed. The bundled sql-formatter code runs offline and is a layout engine, not a SQL validator.

Troubleshooting

• No candidate found: confirm the source uses a supported literal and that the first logical line has -- sql/--sql, or that a listed keyword is at the source-level start with a word boundary.
• Unsupported literal or unsafe f-string: remove concatenation, bytes or t-string syntax, and verify that Python parses the document. Complex f-string expressions are skipped when their source spans cannot be restored exactly.
• Formatting is unavailable: use a trusted workspace and check the diagnostic reason shown by the extension (WORKSPACE_UNTRUSTED, INVALID_CONFIGURATION, PROCESS_TIMEOUT, or PROCESS_FAILED).
• SQL looks different than expected: formatting does not validate SQL or infer a dialect. Adjust the settings above and review the source-level candidate before applying the one-step edit.

For security reporting, see SECURITY.md. For source-free bug reports and diagnostic reason codes, see SUPPORT.md. Licensing and component provenance are in THIRD_PARTY_NOTICES.md.