Enable subqueries inside views

[jepett0]

Ticket

• views: IN (< subquery >) clause cannot be used in view queries #10521

Please see the ticket for the problem description.

Context

Views store only the text of the query that was used to create them. Nevertheless, we build the AST node of the view's select statement to validate it during the parsing of the CREATE VIEW statement.

Our goal is to validate view queries as strictly as possible. This means we validate the view query using a parser context that closely resembles the one that would be created when the view is queried.

Let's name the three parser contexts that are relevant for views:

1. Creation Parser Context. The context in which the CREATE VIEW statement is executed.
2. Validation Parser Context. Used for view query validation.
3. Execution Parser Context. Used during the execution of a SELECT statement from a view.

Using the creation context for validation would allow queries with references to named expressions defined in the creation context to pass validation, which we want to avoid. Unfortunately, implementing this restriction introduces some issues.

Cause

The view validation context lacks blocks to store subquery references. Unlike the TSqlQuery translator, we cannot simply create new blocks because the query references we create must be passed back to the parent context for further translation.

The only viable solution I see is to use the blocks from the current parent context within the validation context. This approach has been implemented in this pull request.

Note

The main commit is:

• 6424ed6

The others are supplementary.

[github-actions]

⚪ 2024-10-16 13:31:44 UTC Pre-commit check linux-x86_64-relwithdebinfo for 1492f71 has started.
⚪ 2024-10-16 13:31:56 UTC Artifacts will be uploaded here
⚪ 2024-10-16 13:35:04 UTC ya make is running...
🟡 2024-10-16 14:35:29 UTC Some tests failed, follow the links below. Going to retry failed tests...

Test history | Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
76072	62099	0	1	13870	102

⚪ 2024-10-16 14:43:31 UTC ya make is running... (failed tests rerun, try 2)
🟢 2024-10-16 14:55:17 UTC Tests successful.

Test history | Ya make output | Test bloat | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
102 (only retried tests)	4	0	0	0	98

🟢 2024-10-16 14:55:24 UTC Build successful.
🟢 2024-10-16 14:55:43 UTC ydbd size 2.8 GiB changed* by +29.0 KiB, which is < 100.0 KiB vs main: OK

ydbd size dash	main: 362f6f5	merge: 1492f71	diff	diff %
ydbd size	3 027 720 680 Bytes	3 027 750 328 Bytes	+29.0 KiB	+0.001%
ydbd stripped size	480 017 112 Bytes	480 017 880 Bytes	+768 Bytes	+0.000%

^{*please be aware that the difference is based on comparing your commit and the last completed build from the post-commit, check comparation}

[github-actions]

⚪ 2024-10-16 13:33:41 UTC Pre-commit check linux-x86_64-release-asan for 1492f71 has started.
⚪ 2024-10-16 13:33:45 UTC Artifacts will be uploaded here
⚪ 2024-10-16 13:36:42 UTC ya make is running...
🟡 2024-10-16 14:58:00 UTC Some tests failed, follow the links below. This fail is not in blocking policy yet

Test history | Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
13185	12937	0	56	90	102

🟢 2024-10-16 14:59:06 UTC Build successful.
🟢 2024-10-16 14:59:42 UTC ydbd size 5.7 GiB changed* by +62.7 KiB, which is < 100.0 KiB vs main: OK

ydbd size dash	main: 362f6f5	merge: 1492f71	diff	diff %
ydbd size	6 128 233 176 Bytes	6 128 297 400 Bytes	+62.7 KiB	+0.001%
ydbd stripped size	1 529 059 856 Bytes	1 529 061 456 Bytes	+1.6 KiB	+0.000%

^{*please be aware that the difference is based on comparing your commit and the last completed build from the post-commit, check comparation}