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Pin NULL-is-smallest ORDER BY on PostgreSQL - #5
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The keyset seek (_keyset_leg_sql) and the evaluator's _null_safe_cmp both assume NULL sorts as the smallest value in both directions -- SQLite's default. compile_query emitted a bare ASC/DESC, and PostgreSQL's default is the opposite (NULL last in ASC, first in DESC), so results reordered relative to SQLite and keyset paging dropped rows. The PostgreSQL dialect now emits ASC NULLS FIRST / DESC NULLS LAST. SQLite output is unchanged. The handle tiebreaker stays bare: it's the NOT NULL primary key, so the clause would change nothing there. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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Fixes #4.
Problem
The keyset seek (
_keyset_leg_sql) and the evaluator's_null_safe_cmpboth assume NULL sorts as the smallest value in both directions, which is SQLite's default.compile_queryemitted a bareASC/DESC. PostgreSQL's default is the opposite: NULL sorts last inASCand first inDESC. As a result, PostgreSQL ordered results differently from SQLite, and keyset paging dropped rows.Fix
_order_direction_sql: the PostgreSQL dialect emitsASC NULLS FIRST/DESC NULLS LAST. SQLite output is unchanged.handletiebreaker stays bare. It's the NOT NULL primary key, so the clause would change nothing there.query.pyandproxied_query.pynow say the order is set explicitly on PostgreSQL.Testing
Updated 2 SQL-string assertions and added 2 tests: PostgreSQL gets the NULLS clauses in both directions, and SQLite gets none. All 741 tests pass.
gramps-web-api's
tests/test_object_query_parsing.pypasses against this branch (120 tests).On a real PostgreSQL server (SharedPostgreSQL dev tree, 7,262 people, 5,359 with no birth place), sorted by
birth.place.titleand paged 500 at a time with keyset cursors:ascpageddescpaged🤖 Generated with Claude Code