fix issue of actions dag split

[Algunenano]

Changelog category (leave one):

• Bug Fix (user-visible misbehavior in an official stable release)

Changelog entry (a user-readable short description of the changes that goes to CHANGELOG.md):

• ActionsDAG::split can't make sure that "Execution of first then second parts on block is equivalent to execution of initial DAG."

Documentation entry for user-facing changes

Continues from #60206

[robot-clickhouse]

This is an automated comment for commit b3e9f07 with description of existing statuses. It's updated for the latest CI running

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Check name	Description	Status
AST fuzzer	Runs randomly generated queries to catch program errors. The build type is optionally given in parenthesis. If it fails, ask a maintainer for help	❌ failure
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Integration tests	The integration tests report. In parenthesis the package type is given, and in square brackets are the optional part/total tests	❌ failure

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[Algunenano]

It failed a fast test and it seems related (doesn't fail without the change) so it seems this required a more detailed investigation. Reverting the offending PR is hard since a) there have been multiple changes after it and b) multiple fuzzer issues (aka crashes) were closed by those changes, so simply going back to the old code isn't a good option.

[Algunenano]

Suggested change

	now() as date,
	1::UInt32 as date,

To use correct types. In the current release it reproduces:

Code: 352. DB::Exception: Received from clickhouse-01:49000. DB::Exception: Block structure mismatch in (columns with identical name must have identical structure) stream: different columns:
date UInt32 UInt32(size = 0)
date UInt32 Const(size = 0, UInt32(size = 1)). (AMBIGUOUS_COLUMN_NAME)

[Algunenano]

@taiyang-li We are changing the code to cover the broken test in a simpler way. Do you have some other test that might fail in this case? Note that the original patch in the PR introduced multiple columns as input which lead to them being loaded unnecessarily, which is why 02263_lazy_mark_load failed.

[taiyang-li]

@taiyang-li We are changing the code to cover the broken test in a simpler way. Do you have some other test that might fail in this case? Note that the original patch in the PR introduced multiple columns as input which lead to them being loaded unnecessarily, which is why 02263_lazy_mark_load failed.

It seems still can't solve the issue described here: #60206 (comment). If the patch from #60206 is removed, it breaks the invariant described in comments of ActionsDAG::split.

/// Split ActionsDAG into two DAGs, where first part contains all nodes from split_nodes and their children.
/// Execution of first then second parts on block is equivalent to execution of initial DAG.
/// First DAG and initial DAG have equal inputs, second DAG and initial DAG has equal outputs.
/// Second DAG inputs may contain less inputs then first DAG (but also include other columns).
SplitResult split(std::unordered_set<const Node *> split_nodes, bool create_split_nodes_mapping = false) const;

[KochetovNicolai]

Integration tests (tsan) [4/6] - #59631

[KochetovNicolai]

@taiyang-li in the example from #60206 (comment) split is correct.
The main invariant of split is that the execution of splitted DAGs one by one is equivalent of execution of original DAG. This is still true.
The part First DAG and initial DAG have equal inputs, second DAG and initial DAG has equal outputs. is not true anymore, I will remove the comment.