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cypher_with: add ORDER BY to non-deterministic RETURN queries#2436

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cypher_with: add ORDER BY to non-deterministic RETURN queries#2436
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Several cypher_with regression queries RETURN multiple rows without an ORDER BY, so their row order depends on heap/scan order and can vary between runs, build types, and platforms. Add ORDER BY ASC to those queries so the expected output is stable. Ordering keys use id() (a single int64 that bypasses the locale-sensitive string comparison path and is reproducible from the test's deterministic setup order), or the projected path/scalar where that is what the query returns. Where the underlying vertex/edge was dropped by a WITH projection, its id is threaded through as an alias rather than reordering the projection.

Full audit of cypher_with: all 23 multi-row result blocks were checked. After this change, every multi-row, non-EXPLAIN RETURN is deterministically ordered. The two remaining unordered multi-row blocks are left as-is:

  • "RETURN lbl" returns two identical "Person" rows, so order cannot drift;
  • the 13 EXPLAIN (VERBOSE, COSTS OFF) plan blocks emit a fixed serial plan (no parallel/gather nodes), so their row order is already deterministic.

This is a test-only change (regress/sql/cypher_with.sql and regress/expected/cypher_with.out); no extension C code or SQL is modified. Row counts are unchanged (pure reordering).

All 37 regression tests pass (installcheck) on PostgreSQL 18.3.

Co-authored-by: GitHub Copilot noreply@github.com

modified: regress/expected/cypher_with.out
modified: regress/sql/cypher_with.sql

Several cypher_with regression queries RETURN multiple rows without an
ORDER BY, so their row order depends on heap/scan order and can vary
between runs, build types, and platforms. Add ORDER BY ASC to those
queries so the expected output is stable. Ordering keys use id() (a
single int64 that bypasses the locale-sensitive string comparison path
and is reproducible from the test's deterministic setup order), or the
projected path/scalar where that is what the query returns. Where the
underlying vertex/edge was dropped by a WITH projection, its id is
threaded through as an alias rather than reordering the projection.

Full audit of cypher_with: all 23 multi-row result blocks were checked.
After this change, every multi-row, non-EXPLAIN RETURN is deterministically
ordered. The two remaining unordered multi-row blocks are left as-is:
- "RETURN lbl" returns two identical "Person" rows, so order cannot drift;
- the 13 EXPLAIN (VERBOSE, COSTS OFF) plan blocks emit a fixed serial plan
  (no parallel/gather nodes), so their row order is already deterministic.

This is a test-only change (regress/sql/cypher_with.sql and
regress/expected/cypher_with.out); no extension C code or SQL is modified.
Row counts are unchanged (pure reordering).

All 37 regression tests pass (installcheck) on PostgreSQL 18.3.

Co-authored-by: GitHub Copilot <noreply@github.com>

modified:   regress/expected/cypher_with.out
modified:   regress/sql/cypher_with.sql

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