Fix: Dremio AT BRANCH/TAG/REF/COMMIT dropped in CTAS, CREATE VIEW, INSERT

[Copilot]

format_statement extracted the Dremio version clause correctly but only forwarded it to the Statement::Query arm. The CTAS, CREATE VIEW, and INSERT arms all called their inner query formatters with version: None, silently dropping the clause and changing query semantics.

Changes

• src/format/sql/mod.rs: Thread version: Option<DremioVersionClause> through format_create_table_with_query, format_create_view, and format_insert; pass it to the inner format_query/format_query_with_layout_preference call instead of None; update all three call sites in format_statement
• fixtures/dremio/out/12.sql: Correct expected output to preserve AT COMMIT 'a1b2c3d4' in the CTAS statement
• fixtures/dremio/in/17.sql / out/17.sql: New regression fixtures covering all four affected statement types
• Tests: Three new unit tests — preserves_version_clause_in_ctas, preserves_version_clause_in_create_view, preserves_version_clause_in_insert_select

Example

Before:

-- Input
CREATE TABLE snap AS SELECT * FROM sales.orders AT COMMIT 'a1b2c3d4';

-- Output (wrong — clause silently dropped)
CREATE TABLE snap AS
SELECT *
FROM sales.orders;

After:

-- Output (correct)
CREATE TABLE snap AS
SELECT *
FROM sales.orders
AT COMMIT 'a1b2c3d4';

Original prompt

Summary

Fixes #2.

sqlchisel drops Dremio versioned table-reference clauses (AT BRANCH|TAG|REF|COMMIT, optional AS OF TIMESTAMP) when the source query is nested inside a CREATE TABLE ... AS, CREATE VIEW ... AS, or INSERT INTO ... SELECT statement. Top-level SELECT already works correctly.

This changes query semantics and violates the expected behavior that formatting should never change what SQL does.

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Root Cause

In src/parser.rs, strip_dremio_version_clause correctly extracts the version clause and stores it in ParsedStatement::Sql { version: Some(...), .. }. However, in src/format/sql/mod.rs, format_statement only threads version through to format_query for the top-level Statement::Query arm. The CTAS, CREATE VIEW, and INSERT arms all call their inner query formatters with version: None, silently dropping the clause.

Broken call sites (all pass version: None today):

• format_create_table_with_query → format_query_with_layout_preference(..., None, ...)
• format_create_view → format_query(..., None, ...)
• format_insert → format_query(..., None, ...)

---

Required Changes

1. src/format/sql/mod.rs

Thread the version: Option<DremioVersionClause> parameter through the three broken formatter functions:

• format_create_table_with_query: Add version: Option<DremioVersionClause> parameter. Pass it to format_query_with_layout_preference instead of None. Update its call site in format_statement to pass version.
• format_create_view: Add version: Option<DremioVersionClause> parameter. Pass it to format_query instead of None. Update its call site in format_statement to pass version.
• format_insert: Add version: Option<DremioVersionClause> parameter. Pass it to format_query instead of None. Update its call site in format_statement to pass version.

The version value is already available in format_statement — it is extracted from ParsedStatement::Sql { version, .. } and currently only used for the Statement::Query arm. It must also be passed to the above three arms.

2. fixtures/dremio/out/12.sql

The existing CTAS fixture (fixtures/dremio/in/12.sql) contains AT COMMIT 'a1b2c3d4' but fixtures/dremio/out/12.sql drops it. Update the expected output to preserve the clause:

Current (wrong):

CREATE TABLE demoCatalog.sales.snapshot_orders AS
SELECT * FROM demoCatalog.sales."orders_history";

Expected (correct):

CREATE TABLE demoCatalog.sales.snapshot_orders AS
SELECT *
FROM demoCatalog.sales."orders_history"
AT COMMIT 'a1b2c3d4';

3. New regression fixtures

Add fixtures/dremio/in/13.sql and fixtures/dremio/out/13.sql covering all four statement types.

fixtures/dremio/in/13.sql:

CREATE TABLE a AS SELECT * FROM s.t AT TAG v1;
CREATE VIEW v AS SELECT * FROM s.t AT TAG v1;
INSERT INTO a SELECT * FROM s.t AT TAG v1;
SELECT * FROM s.t AT TAG v1;

fixtures/dremio/out/13.sql: The correctly-formatted version preserving all version clauses.

4. Tests

Add regression tests (unit or integration) verifying that format_sql with DialectKind::Dremio preserves the version clause in:

• CTAS (CREATE TABLE ... AS SELECT ... AT TAG)
• CREATE VIEW AS (with AT TAG)
• INSERT INTO ... SELECT (with AT TAG)
• Top-level SELECT (already passing — add a test to prevent regression)

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Acceptance Criteria

• AT BRANCH|TAG|REF|COMMIT and AS OF TIMESTAMP are preserved in: CTAS, CREATE VIEW AS, INSERT ... SELECT, and top-level SELECT.
• fixtures/dremio/out/12.sql is corrected.
• New regression fixtures fixtures/dremio/in/13.sql and fixtures/dremio/out/13.sql are added.
• Tests pass for all four statement types.
• No existing tests are broken.

This pull request was created from Copilot chat.

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