…#69399 (#69560)

### What problem does this PR solve?

Related PR: #69399

Problem Summary: Backport #69399 to `branch-4.2`.

A CTE fails to plan with "A expression contains slot not from children"
when the optimizer inlines it after one of its scans got a virtual
column: a CTE that orders by `score()` or by an ANN distance with a
LIMIT, or that has MATCH in its select list and is inlined after
rewrite. `LogicalPlanDeepCopier` gave each virtual column two ids,
copied them in list order, kept the old slot in the output of the copied
scan and left the score and ANN order keys on the old slots. The copier
now maps every virtual column to its new id before copying their
expressions and remaps the order keys, and
`LogicalOlapScan.withVirtualColumns` replaces the old virtual slots in
the output.

#### Branch adaptations

The branch has no table streams, so the change to
`LogicalOlapTableStreamScan` is dropped. `withVirtualColumns` keeps the
constructor call of the branch, `LogicalPlanDeepCopier` imports
`LogicalOlapScan`, which master already imported, and
`LogicalPlanDeepCopierTest` keeps the tests of the branch and adds the
two tests of #69399.

### Release note

Fix "A expression contains slot not from children" for a CTE that orders
by `score()` or by an ANN distance with a LIMIT, or that has MATCH in
its select list and is inlined after rewrite.

### Check List (For Author)

- Test
    - [x] Regression test
    - [x] Unit Test
    - [ ] Manual test
- Behavior changed:
    - [x] No.
- Does this need documentation?
    - [x] No.

### Validation

Validated together with the other two backports (#69399, #69419 and
#69292 on `branch-4.2` at ecbc5fe), in a local ASAN build:

- PASS: FE unit tests `LogicalPlanDeepCopierTest`, `CTEInlineTest`,
`InferPredicateByReplaceTest`, `InferPredicatesTest`,
`UnequalPredicateInferTest`, `BindScoreToOlapScanTest`,
`SearchExpressionTest`, `TopNRuntimeFilterTest`,
`PullUpProjectExprUnderTopNTest` and `MaterializedViewUtilsTest` (280
tests), and FE Checkstyle.
- PASS: `./build.sh --fe --be`.
- PASS: BE unit tests `SegmentIteratorScoreCommonExprTest`,
`SegmentIteratorApplyIndexExprTest` and `VirtualSlotRefTest` (31 tests);
clang-format 16 on the changed BE files.
- PASS: the 23 regression suites of the branch that use `score()`,
including `test_cte_inline_virtual_column`, `infer_match_predicate`,
`test_score_filter_usage` and `test_score_filter_matrix`, with unchanged
`.out` files.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Opus 5.5 <[email protected]>

…69292 (#69562)

### What problem does this PR solve?

Related PR: #69292

Problem Summary: Backport #69292 to `branch-4.2`. It contains the commit
of #69560, the backport of #69399, which it needs: binding runs before
CTE inlining, which copies scans with virtual columns. Merge #69560
first.

`score()` only worked as `ORDER BY score() LIMIT n` directly above the
scan whose MATCH defines it. A minimum score filter without that TopN
evaluated the unbound `score()` placeholder as zero and silently dropped
every row:

```sql
SELECT id FROM documents WHERE content MATCH 'apple' AND score() > 0.00001;  -- returned nothing
```

`BindScoreToOlapScan`, which replaces `CheckScoreUsage`, binds `score()`
to the scan of its SELECT at the start of rewrite and rejects the uses
it cannot bind. The minimum score stays a predicate of the scan, and
`PushDownScoreTopNIntoOlapScan` still pushes a TopN on the score
together with the minimum. In the BE, an expression on the score reads
the score column instead of evaluating `Score()`, and MATCH projections
do not add to the score. See #69292 for the supported and rejected uses.

#### Branch adaptations

- The `SegmentIterator` of the branch collects the columns of
pushed-down expressions in `_extract_common_expr_columns` instead of
per-column states, so the score column is marked there, and the new BE
test checks `_common_expr_columns` and `_is_common_expr_column`. The
branch reads the columns collected there before it evaluates the
expressions, also virtual ones, and a virtual slot uses a column that is
already read.
- When `limit + offset` overflows, `PushDownScoreTopNIntoOlapScan` keeps
the behavior of the branch and skips the push-down instead of failing.
- `SearchDslParser` is imported from its package on the branch.
- The branch does not have #68672, which keeps predicates on virtual
columns out of the condition cache. The minimum score is now a predicate
of the scan, and a score depends on every rowset, so a cached result
goes stale when a rowset is added: without the change,
`test_score_filter_matrix` lost the rows of the first rowset.
`VirtualSlotRef::get_digest` returns 0 as on master, the part of #68672
that this needs, with the `VirtualSlotRef` tests of #68672 that the
branch can run.

### Release note

`score()` works in the select list, window functions and ORDER BY of a
SELECT on one table whose WHERE clause has MATCH or SEARCH, with an
optional minimum score `score() > x` or `score() >= x`, without `ORDER
BY score() LIMIT`. A scored SELECT in a subquery, view, CTE or set
operation still needs `ORDER BY score() LIMIT`. Other uses of `score()`
are rejected instead of evaluating it as 0.

### Check List (For Author)

- Test
    - [x] Regression test
    - [x] Unit Test
    - [ ] Manual test
- Behavior changed:
- [x] Yes. A minimum score works without `ORDER BY score() LIMIT`, and
unsupported uses of `score()` fail planning instead of evaluating it as
0. A minimum score without a TopN needs the BE change, so BEs must be
upgraded before FEs.
- Does this need documentation?
- [x] Yes. The `score()` documentation should describe where `score()`
can be used.

### Validation

Validated together with the other two backports (#69399, #69419 and
#69292 on `branch-4.2` at ecbc5fe), in a local ASAN build:

- PASS: FE unit tests `LogicalPlanDeepCopierTest`, `CTEInlineTest`,
`InferPredicateByReplaceTest`, `InferPredicatesTest`,
`UnequalPredicateInferTest`, `BindScoreToOlapScanTest`,
`SearchExpressionTest`, `TopNRuntimeFilterTest`,
`PullUpProjectExprUnderTopNTest` and `MaterializedViewUtilsTest` (280
tests), and FE Checkstyle.
- PASS: `./build.sh --fe --be`.
- PASS: BE unit tests `SegmentIteratorScoreCommonExprTest`,
`SegmentIteratorApplyIndexExprTest` and `VirtualSlotRefTest` (31 tests);
clang-format 16 on the changed BE files.
- PASS: the 23 regression suites of the branch that use `score()`,
including `test_cte_inline_virtual_column`, `infer_match_predicate`,
`test_score_filter_usage` and `test_score_filter_matrix`, with unchanged
`.out` files.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 5.5 <[email protected]>

…cross column equalities #69419 (#69561)

### What problem does this PR solve?

Related PR: #69419

Problem Summary: Backport #69419 to `branch-4.2`.

Predicate inference copied a predicate on one column to every column
that is equal to it, also when the predicate contained MATCH,
multi_match or SEARCH. Their result depends on the inverted index of the
column, not only on its value: with `c1 = c2` and different parsers on
the two columns, the copy removed matching rows, and with the same index
it doubled `score()`, so a minimum score let low-scored rows through.
`InferPredicateByReplace.infer` now skips every input that contains
`Match`, `MultiMatch`, `Search` or `SearchExpression`.

#### Branch adaptations

The branch does not have the `NoneMovableFunction` check that master has
next to the new check, so only the new check is added. The test imports
`SearchDslParser` from its package on the branch.

### Release note

Fix wrong results and scores when predicate inference copied a MATCH,
multi_match or SEARCH predicate to an equal column.

### Check List (For Author)

- Test
    - [x] Regression test
    - [x] Unit Test
    - [ ] Manual test
- Behavior changed:
- [x] Yes. Predicate inference no longer copies a predicate that
contains MATCH, multi_match or SEARCH to an equal column.
- Does this need documentation?
    - [x] No.

### Validation

Validated together with the other two backports (#69399, #69419 and
#69292 on `branch-4.2` at ecbc5fe), in a local ASAN build:

- PASS: FE unit tests `LogicalPlanDeepCopierTest`, `CTEInlineTest`,
`InferPredicateByReplaceTest`, `InferPredicatesTest`,
`UnequalPredicateInferTest`, `BindScoreToOlapScanTest`,
`SearchExpressionTest`, `TopNRuntimeFilterTest`,
`PullUpProjectExprUnderTopNTest` and `MaterializedViewUtilsTest` (280
tests), and FE Checkstyle.
- PASS: `./build.sh --fe --be`.
- PASS: BE unit tests `SegmentIteratorScoreCommonExprTest`,
`SegmentIteratorApplyIndexExprTest` and `VirtualSlotRefTest` (31 tests);
clang-format 16 on the changed BE files.
- PASS: the 23 regression suites of the branch that use `score()`,
including `test_cte_inline_virtual_column`, `infer_match_predicate`,
`test_score_filter_usage` and `test_score_filter_matrix`, with unchanged
`.out` files.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Opus 5.5 <[email protected]>

### What problem does this PR solve?

Related PR: apache#69292

Problem Summary: CI on branch-4.1 draws enable_common_expr_pushdown at
random for each session. With it off, MATCH is not evaluated with the
inverted index in the scan, so no BM25 score is collected and score()
returns 0. test_score_filter_usage and test_score_filter_matrix got no
rows for a minimum score, and test_cte_inline_virtual_column got score
0.0 for its TopN. Like the score suites of the branch, these suites set
enable_common_expr_pushdown = true.

### Release note

None

### Check List (For Author)

- Test: Regression test. With use_fuzzy_session_variable = true and
the pull request number of CI, the three suites failed in sessions
that drew enable_common_expr_pushdown = false (1 to 3 suites per run);
with the setting pinned, four runs passed.
- Behavior changed: No
- Does this need documentation: No

Co-Authored-By: Claude Opus 5.5 <[email protected]>

…#69399 (#69563)

### What problem does this PR solve?

Related PR: #69399

Problem Summary: Backport #69399 to `branch-4.1`.

A CTE fails to plan with "A expression contains slot not from children"
when the optimizer inlines it after one of its scans got a virtual
column: a CTE that orders by `score()` or by an ANN distance with a
LIMIT, or that has MATCH in its select list and is inlined after
rewrite. `LogicalPlanDeepCopier` gave each virtual column two ids,
copied them in list order, kept the old slot in the output of the copied
scan and left the score and ANN order keys on the old slots. The copier
now maps every virtual column to its new id before copying their
expressions and remaps the order keys, and
`LogicalOlapScan.withVirtualColumns` replaces the old virtual slots in
the output.

#### Branch adaptations

The branch has no table streams, so the change to
`LogicalOlapTableStreamScan` is dropped. `withVirtualColumns` keeps the
constructor call of the branch, and `LogicalPlanDeepCopierTest` and
`CTEInlineTest` keep the tests of the branch and add the tests of
#69399. `test_cte_inline_virtual_column` sets
`enable_common_expr_pushdown = true`, as the score suites of the branch
do: CI on branch-4.1 draws it at random for each session, and without it
MATCH is not evaluated with the index in the scan and `score()` is 0.

### Release note

Fix "A expression contains slot not from children" for a CTE that orders
by `score()` or by an ANN distance with a LIMIT, or that has MATCH in
its select list and is inlined after rewrite.

### Check List (For Author)

- Test
    - [x] Regression test
    - [x] Unit Test
    - [ ] Manual test
- Behavior changed:
    - [x] No.
- Does this need documentation?
    - [x] No.

### Validation

Validated together with the other two backports (#69399, #69419 and
#69292 on `branch-4.1` at 3f911d0), in a local ASAN build:

- PASS: FE unit tests `LogicalPlanDeepCopierTest`, `CTEInlineTest`,
`InferPredicateByReplaceTest`, `InferPredicatesTest`,
`UnequalPredicateInferTest`, `BindScoreToOlapScanTest`,
`SearchExpressionTest`, `TopNRuntimeFilterTest` and
`MaterializedViewUtilsTest` (228 tests), and FE Checkstyle.
- PASS: `./build.sh --be` and `./build.sh --fe`.
- PASS: BE unit tests `SegmentIteratorScoreCommonExprTest`,
`SegmentIteratorApplyIndexExprTest` and `VirtualSlotRefTest` (31 tests);
clang-format 16 on the changed BE files.
- PASS: the 16 regression suites of the branch that use `score()`,
including `test_cte_inline_virtual_column`, `infer_match_predicate`,
`test_score_filter_usage` and `test_score_filter_matrix`. The framework
regenerated the `.out` of `test_score_filter_matrix` on this branch: it
drops the 46 SNII cases and keeps the 94 V2 and V3 cases of master
unchanged. The other `.out` files are unchanged.
- PASS: with the fuzzy session variables of CI
(`use_fuzzy_session_variable = true` and its pull request number), the
score suites failed in sessions that drew `enable_common_expr_pushdown =
false`; with the setting pinned, four runs of `test_score_filter_usage`,
`test_score_filter_matrix` and `test_cte_inline_virtual_column`, and
four of `infer_match_predicate`, passed.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 5.5 <[email protected]>

…cross column equalities #69419 (#69564)

### What problem does this PR solve?

Related PR: #69419

Problem Summary: Backport #69419 to `branch-4.1`.

Predicate inference copied a predicate on one column to every column
that is equal to it, also when the predicate contained MATCH,
multi_match or SEARCH. Their result depends on the inverted index of the
column, not only on its value: with `c1 = c2` and different parsers on
the two columns, the copy removed matching rows, and with the same index
it doubled `score()`, so a minimum score let low-scored rows through.
`InferPredicateByReplace.infer` now skips every input that contains
`Match`, `MultiMatch`, `Search` or `SearchExpression`.

#### Branch adaptations

The branch does not have the `NoneMovableFunction` check that master has
next to the new check, so only the new check is added. The test imports
`SearchDslParser` from its package on the branch.
`infer_match_predicate` sets `enable_common_expr_pushdown = true`, as
the score suites of the branch do: CI on branch-4.1 draws it at random
for each session, and without it MATCH is not evaluated with the index
in the scan and `score()` is 0.

### Release note

Fix wrong results and scores when predicate inference copied a MATCH,
multi_match or SEARCH predicate to an equal column.

### Check List (For Author)

- Test
    - [x] Regression test
    - [x] Unit Test
    - [ ] Manual test
- Behavior changed:
- [x] Yes. Predicate inference no longer copies a predicate that
contains MATCH, multi_match or SEARCH to an equal column.
- Does this need documentation?
    - [x] No.

### Validation

Validated together with the other two backports (#69399, #69419 and
#69292 on `branch-4.1` at 3f911d0), in a local ASAN build:

- PASS: FE unit tests `LogicalPlanDeepCopierTest`, `CTEInlineTest`,
`InferPredicateByReplaceTest`, `InferPredicatesTest`,
`UnequalPredicateInferTest`, `BindScoreToOlapScanTest`,
`SearchExpressionTest`, `TopNRuntimeFilterTest` and
`MaterializedViewUtilsTest` (228 tests), and FE Checkstyle.
- PASS: `./build.sh --be` and `./build.sh --fe`.
- PASS: BE unit tests `SegmentIteratorScoreCommonExprTest`,
`SegmentIteratorApplyIndexExprTest` and `VirtualSlotRefTest` (31 tests);
clang-format 16 on the changed BE files.
- PASS: the 16 regression suites of the branch that use `score()`,
including `test_cte_inline_virtual_column`, `infer_match_predicate`,
`test_score_filter_usage` and `test_score_filter_matrix`. The framework
regenerated the `.out` of `test_score_filter_matrix` on this branch: it
drops the 46 SNII cases and keeps the 94 V2 and V3 cases of master
unchanged. The other `.out` files are unchanged.
- PASS: with the fuzzy session variables of CI
(`use_fuzzy_session_variable = true` and its pull request number), the
score suites failed in sessions that drew `enable_common_expr_pushdown =
false`; with the setting pinned, four runs of `test_score_filter_usage`,
`test_score_filter_matrix` and `test_cte_inline_virtual_column`, and
four of `infer_match_predicate`, passed.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 5.5 <[email protected]>

…69292 (#69565)

### What problem does this PR solve?

Related PR: #69292

Problem Summary: Backport #69292 to `branch-4.1`. It contains the commit
of #69563, the backport of #69399, which it needs: binding runs before
CTE inlining, which copies scans with virtual columns. Merge #69563
first.

`score()` only worked as `ORDER BY score() LIMIT n` directly above the
scan whose MATCH defines it. A minimum score filter without that TopN
evaluated the unbound `score()` placeholder as zero and silently dropped
every row:

```sql
SELECT id FROM documents WHERE content MATCH 'apple' AND score() > 0.00001;  -- returned nothing
```

`BindScoreToOlapScan`, which replaces `CheckScoreUsage`, binds `score()`
to the scan of its SELECT at the start of rewrite and rejects the uses
it cannot bind. The minimum score stays a predicate of the scan, and
`PushDownScoreTopNIntoOlapScan` still pushes a TopN on the score
together with the minimum. In the BE, an expression on the score reads
the score column instead of evaluating `Score()`, and MATCH projections
do not add to the score. See #69292 for the supported and rejected uses.

#### Branch adaptations

- The `SegmentIterator` of the branch collects the columns of
pushed-down expressions in `_extract_common_expr_columns` instead of
per-column states, so the score column is marked there, and the new BE
test checks `_common_expr_columns` and `_is_common_expr_column`. The
branch reads the columns collected there before it evaluates the
expressions, also virtual ones, and a virtual slot uses a column that is
already read.
- The branch evaluates MATCH projections with `evaluate_inverted_index`
directly, and that loop runs without the score collector.
- `PushDownScoreTopNIntoOlapScan` keeps the overflow check of the branch
for `limit + offset`, which fails like master does.
- `SearchDslParser` and `CollectionSimilarity` are included from their
packages on the branch.
- The branch has no SNII storage format, so `BindScoreToOlapScanTest`
and `test_score_filter_matrix` cover V2 and V3, and the `.out` of
`test_score_filter_matrix` is regenerated without the SNII cases.
- The branch does not have #68672, which keeps predicates on virtual
columns out of the condition cache. The minimum score is now a predicate
of the scan, and a score depends on every rowset, so a cached result
goes stale when a rowset is added: without the change,
`test_score_filter_matrix` lost the rows of the first rowset.
`VirtualSlotRef::get_digest` returns 0 as on master, the part of #68672
that this needs, with the `VirtualSlotRef` tests of #68672 that the
branch can run.
- `test_score_filter_usage`, `test_score_filter_matrix` and
`test_cte_inline_virtual_column` set `enable_common_expr_pushdown =
true`, as the score suites of the branch do: CI on branch-4.1 draws it
at random for each session, and without it MATCH is not evaluated with
the index in the scan and `score()` is 0.

### Release note

`score()` works in the select list, window functions and ORDER BY of a
SELECT on one table whose WHERE clause has MATCH or SEARCH, with an
optional minimum score `score() > x` or `score() >= x`, without `ORDER
BY score() LIMIT`. A scored SELECT in a subquery, view, CTE or set
operation still needs `ORDER BY score() LIMIT`. Other uses of `score()`
are rejected instead of evaluating it as 0.

### Check List (For Author)

- Test
    - [x] Regression test
    - [x] Unit Test
    - [ ] Manual test
- Behavior changed:
- [x] Yes. A minimum score works without `ORDER BY score() LIMIT`, and
unsupported uses of `score()` fail planning instead of evaluating it as
0. A minimum score without a TopN needs the BE change, so BEs must be
upgraded before FEs.
- Does this need documentation?
- [x] Yes. The `score()` documentation should describe where `score()`
can be used.

### Validation

Validated together with the other two backports (#69399, #69419 and
#69292 on `branch-4.1` at 3f911d0), in a local ASAN build:

- PASS: FE unit tests `LogicalPlanDeepCopierTest`, `CTEInlineTest`,
`InferPredicateByReplaceTest`, `InferPredicatesTest`,
`UnequalPredicateInferTest`, `BindScoreToOlapScanTest`,
`SearchExpressionTest`, `TopNRuntimeFilterTest` and
`MaterializedViewUtilsTest` (228 tests), and FE Checkstyle.
- PASS: `./build.sh --be` and `./build.sh --fe`.
- PASS: BE unit tests `SegmentIteratorScoreCommonExprTest`,
`SegmentIteratorApplyIndexExprTest` and `VirtualSlotRefTest` (31 tests);
clang-format 16 on the changed BE files.
- PASS: the 16 regression suites of the branch that use `score()`,
including `test_cte_inline_virtual_column`, `infer_match_predicate`,
`test_score_filter_usage` and `test_score_filter_matrix`. The framework
regenerated the `.out` of `test_score_filter_matrix` on this branch: it
drops the 46 SNII cases and keeps the 94 V2 and V3 cases of master
unchanged. The other `.out` files are unchanged.
- PASS: with the fuzzy session variables of CI
(`use_fuzzy_session_variable = true` and its pull request number), the
score suites failed in sessions that drew `enable_common_expr_pushdown =
false`; with the setting pinned, four runs of `test_score_filter_usage`,
`test_score_filter_matrix` and `test_cte_inline_virtual_column`, and
four of `infer_match_predicate`, passed.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 5.5 <[email protected]>

### Background

SEARCH fields are bound during analysis before score binding runs in rewrite. Bound SEARCH predicates use SearchExpression instead of the scalar Search function.

### What problem does this PR solve?

Issue Number: None
Related PR: apache#69344 (early SEARCH binding), apache#69292 (score binding)
PR Type: Bugfix

Problem Summary: Valid SEARCH queries that call score() are rejected because score binding only recognizes the unbound Search type. Recognize SearchExpression in the WHERE predicate check, scoring alias propagation and HAVING/QUALIFY validation.

### Details

- **Frequency:** SEARCH scoring queries after early SEARCH binding.
- **Root cause:** The downstream score binder checks the expression type from the previous rule ordering.
- **Why existing tests missed it:** The targeted SEARCH suites did not cover score(); existing score regression suites expose the failure.
- **Fix:** Replace all three Search type checks with SearchExpression and update the import.
- **Other paths and branches:** MATCH recognition and score usage restrictions remain unchanged.
- **Behavior change:** Valid SEARCH scoring queries can pass score binding.

### Testing

FE Checkstyle and git diff --check passed. Built FE with DISABLE_BUILD_UI=ON ./build.sh --fe and deployed it to the development cluster.

The five targeted FE test classes executed 147 tests with zero failures, errors or skips, including 82 BindScoreToOlapScanTest cases.

Ran 21 targeted regression suites: 20 passed, one failed because the existing BE lacks the keyword MATCH scoring change from apache#69790. Its actual 0.290716 score matches the BE-version expected output, while the current expected output is 0.983863. Re-running that suite against the existing generated expected output from the running BE commit passed. Repository expected outputs were not changed. The previous SEARCH score binding error was not reproduced.

The initial local FE unit-test attempt stopped during dependency resolution due to Maven-cache sandbox permissions; remote tests provide the validation above.

### Release note

Fix planning failures when using score() with SEARCH predicates.

### Check List (For Author)

- Behavior changed: Yes (see Details)
- Does this need documentation: No
- Pre-submission status: Partially verified: current keyword MATCH expected scores require a BE containing apache#69790; validation used the existing BE

### AI Disclosure

- Tool: OpenAI Codex
- Generated: Code and commit description
- Human review: Pending

Doris 4.0.0 through 4.0.3 reject `score()` predicates in `WHERE`, while
4.0.4 and later support direct minimum-score filtering. Document both
query forms in the English and Chinese dev/4.x relevance guides, with an
indexed sample table and input data. Explain supported score predicates,
threshold semantics, and the candidate limit required by the
older-version workaround. Fixes #3264.

The dev guides also describe the current implementation: an outermost
single-table query can compute and filter scores without Top-N, while a
scored SELECT nested in a subquery, view, CTE, or set operation still
needs score ordering and LIMIT. Update the activation conditions and FAQ
to match. The 4.x guides retain the Top-N requirement verified for 4.0.x
and 4.1.0 through 4.1.5.

Validation:
- Compared the score-filter implementation in the 4.0.0 through 4.0.4
release tags and 4.1.5-release, checked the 4.0.4 release notes and
[#60997](apache/doris#60997), and checked
current master’s `BindScoreToOlapScan` and regression examples from
[#69292](apache/doris#69292).
- All four pages pass MDX parsing after legacy HTML-comment removal,
front matter preservation, English/Chinese SQL example comparison, link
checks, locale/version sync checks, and `git diff --check`.
- No live cluster SQL or full website build was run. Existing page
routes, front matter, and navigation are preserved.

---------

Co-authored-by: morningman <[email protected]>