[fix](case) one_col_range_partition: query a date range that has data

[shuke987]

Problem

one_col_range_partition fails on branch-4.1 P0 at the multi-branch CASE WHEN assertion (~line 256). The CASE WHEN simplifies to dt >= '2021-05-01', but the table's data only spans 2020-01-01 ~ 2021-02-20 (10000 hours), so that range contains no data. The optimizer now correctly prunes the all-empty partitions to 0:VEMPTYSET, so the stale contains("partitions=417/1826") no longer matches.

This is not a correctness bug — the result is correct (0 rows, nothing matches). Verified on a branch-4.1 cluster:

• a plain WHERE dt >= '2021-05-01' also prunes to VEMPTYSET (data-driven empty-partition pruning);
• inserting a row dt = '2021-06-15' immediately flips the plan to partitions=1/1826 and the row is returned — so VEMPTYSET never drops real data.

Fix

Change the CASE WHEN's second threshold to '2021-1-15' (inside the data range) so it prunes to a real, non-empty partition set, and update the expected count to partitions=37/1826. This keeps the assertion verifying that a multi-branch CASE WHEN is correctly pushed into partition pruning.

Scope check: this is the only stale assertion in the suite — the sibling CASE WHEN near line 261 still yields 417/1826 and is left unchanged.

Verification

On a branch-4.1 cluster the rewritten CASE WHEN deterministically prunes to partitions=37/1826 (matching dt >= '2021-01-15').

🤖 Generated with Claude Code

[shuke987]

run buildall

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