feat: Add CreateTable API with simplified single-stage flow #1629

sanujbasu · 2026-01-20T08:35:16Z

🥞 Stacked PR

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stack/create_table_1 [Files changed]
- stack/create_table_2 [Files changed]

Implement create-table functionality where CreateTableTransactionBuilder::build()
returns a Transaction with stored actions to be used for a commit.

API Usage:
let result = create_table(path, schema, engine_info)
.build(engine, committer)?
.commit(engine)?;

This specific change doesn't allow table properties and features to be set and
has validations in the transaction module which error if unsupported features or
properties such as row tracking and ICT are set in the table configuration being
pushed down.

Key Changes:

CreateTableTransactionBuilder::build() takes committer and returns Transaction
with commit info, protocol and metadata actions.
Transaction struct holds optional protocol/metadata actions for create-table
Adds try_new_create_table() constructor alongside try_new_existing_table()
commit() handles both existing-table and create-table flows
get_write_context() now returns DeltaResult for proper error handling

This aligns the Rust Kernel's create-table flow with the Java Kernel's
approach where Transaction is the single unit for all commit operations.

Testing:
Unit and functional tests

codecov · 2026-01-20T08:40:15Z

Codecov Report

❌ Patch coverage is 80.08850% with 45 lines in your changes missing coverage. Please review.
✅ Project coverage is 84.12%. Comparing base (435b94e) to head (15afd12).

Files with missing lines	Patch %	Lines
kernel/src/transaction/mod.rs	72.41%	23 Missing and 9 partials ⚠️
kernel/src/transaction/create_table.rs	85.39%	8 Missing and 5 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1629      +/-   ##
==========================================
- Coverage   84.15%   84.12%   -0.04%     
==========================================
  Files         123      124       +1     
  Lines       34180    34377     +197     
  Branches    34180    34377     +197     
==========================================
+ Hits        28764    28919     +155     
- Misses       4021     4051      +30     
- Partials     1395     1407      +12

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kernel/src/transaction/mod.rs

kernel/tests/create_table.rs

kernel/src/transaction/mod.rs

ffi/src/transaction/write_context.rs

kernel/src/transaction/create_table.rs

kernel/tests/create_table.rs

OussamaSaoudi · 2026-01-20T18:44:03Z

kernel/tests/create_table.rs

+use serde_json::Value;
+use tempfile::tempdir;
+use test_utils::create_default_engine;
+


Add a test for CTAS. Ensure that CREATE table transaction cannot add remove actions.

Ill add that in write integration tests. Issue filed #1647.

kernel/src/transaction/mod.rs

scottsand-db · 2026-01-21T21:15:41Z

kernel/src/transaction/create_table.rs

+/// * `storage` - The storage handler to use for listing
+/// * `delta_log_url` - URL to the `_delta_log` directory
+/// * `table_path` - Original table path (for error messages)
+fn ensure_table_does_not_exist(


Style question: @nicklan or @OussamaSaoudi -- Do we have a style guide on where/when pub functions should be vs private associated functions?

e.g. I (a "java" guy) would imagine a reader would expect/want pub fn create_table to be the top fn in this class, not a private function

(Not a blocker for this review -- can figure out offline)

scottsand-db · 2026-01-21T21:18:45Z

kernel/src/transaction/create_table.rs

+///
+/// This function checks the `_delta_log` directory to determine if a table already exists.
+/// It handles various storage backend behaviors gracefully:
+/// - If the directory doesn't exist (FileNotFound), returns Ok (new table can be created)


Awesome. Perhaps in a future PR, we add tests for each of these cases, to be thorough?

scottsand-db

LGTM! Thanks! Two minor questions (one on code organization, one on test followup) -- non blockers

Implement create-table functionality where CreateTableTransactionBuilder::build() returns a Transaction with stored actions to be used for a commit. API Usage: let result = create_table(path, schema, engine_info) .build(engine, committer)? .commit(engine)?; This specific change doesn't allow table properties and features to be set and has validations in the transaction module which error if unsupported features or properties such as row tracking and ICT are set in the table configuration being pushed down. Key Changes: - CreateTableTransactionBuilder::build() takes committer and returns Transaction with commit info, protocol and metadata actions. - Transaction struct holds optional protocol/metadata actions for create-table - Adds try_new_create_table() constructor alongside try_new_existing_table() - commit() handles both existing-table and create-table flows - get_write_context() now returns DeltaResult<WriteContext> for proper error handling This aligns the Rust Kernel's create-table flow with the Java Kernel's approach where Transaction is the single unit for all commit operations. Testing: Unit tests

Add comprehensive tests validating the basic create_table() functionality introduced. Test coverage includes: - test_create_simple_table: Verifies basic table creation with a multi-column schema, snapshot version (0), and field preservation - test_create_table_already_exists: Validates error handling when attempting to create a table at an existing path - test_create_table_empty_schema: Ensures empty schema validation fails at build time with appropriate error message - test_create_table_log_actions: Verifies delta log structure with correct action ordering (CommitInfo, Protocol, Metadata) for ICT compliance, and validates action contents including engineInfo, operation type, protocol versions, and kernelVersion

github-actions bot assigned sanujbasu Jan 20, 2026

sanujbasu requested a review from OussamaSaoudi January 20, 2026 08:39

sanujbasu linked an issue Jan 20, 2026 that may be closed by this pull request

[EPIC] Create table API support for Kernel Rust #1613

Open

sanujbasu requested a review from scottsand-db January 20, 2026 08:39

sanujbasu force-pushed the stack/create_table_1 branch 2 times, most recently from 1861faa to c41a7cc Compare January 20, 2026 09:21

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