fix: chdb-core 26.5.0 compatibility — composite leaf coercion, PK paren strip, inverted upstream-bug locks (#12)

chdb-core 26.5.0 (the ClickHouse 26.5 baseline, on PyPI 2026-06-08)
changed three behaviors vs 26.3 and turned the nightly CI red:

1. Float / Decimal / temporal leaves inside Array / Tuple / Map /
   Nested / geo cells are now serialised as quoted strings
   ("['1.5', '2.5']" for Array(Float64)) where 26.3 emitted bare
   numerics. The cursor wrapper now walks composite cells recursively,
   driven by the column's ClickHouse type string, and re-coerces
   leaves to native types. Container shapes are preserved as parsed;
   named Tuple cells (returned as dicts by chdb.dbapi) keep the dict
   shape with coerced values.

2. ClickHouse 26.5 preserves wrapping parens around a single-column
   sorting key in system.tables.sorting_key (ORDER BY (user_id) used
   to be reported as user_id), which broke get_pk_constraint with
   constrained_columns=['(user_id)']. Reflection now strips parens
   that wrap the entire expression before splitting.

3. chdb-core 26.5 fixed the two upstream bugs our torture tests
   locked: Decimal(P>18) precision loss (chdb-io/chdb#574) and Float
   NaN/±Inf folding to None (chdb-io/chdb#575). Both locks are
   inverted to assert the fixed behavior, as their failure messages
   prescribed.

The L5 differential reference binary moves from
clickhouse-server:26.3.9.8-lts to clickhouse-server:26.5.1.882 to
match the new baseline; the version-skew sanity test guards the
pairing.

All cursor coercions are no-ops on chdb-core 26.3 native values, so
the wrapper works on both binary generations. New torture tests lock
the leaf repair for each composite shape that regressed.

Co-authored-by: Claude Fable 5 <[email protected]>

Author: ShawnChen-Sirius

.github/workflows/ci.yml

@@ -142,17 +142,17 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.12"
-      - name: Extract clickhouse binary from LTS image
+      - name: Extract clickhouse binary from server image
         run: |
-          # Try tags from most-specific to least-specific. ClickHouse's
-          # Docker Hub publishes some patch tags (``X.Y.Z.W-lts``) and
-          # rolling tags (``X.Y-lts``, ``lts``). The patch-specific tag
-          # may rotate out, so fall back to the rolling tags. The
-          # differential test's own version check ([:3] of version())
-          # will surface any unexpected major.minor.patch drift as a
-          # test failure rather than a silent pass.
+          # The tag must track chdb-core's ClickHouse baseline (26.5.1 as
+          # of chdb-core 26.5.0) — the differential test's own version
+          # check ([:3] of version()) fails loudly on drift, so a chdb
+          # baseline bump shows up here as a red version-skew test, not a
+          # silent pass. Try tags from most-specific to least-specific:
+          # patch tags (``X.Y.Z.W``) may rotate out, so fall back to the
+          # rolling ``X.Y.Z`` / ``X.Y`` tags.
           set -e
-          for tag in "26.3.9.8-lts" "26.3-lts" "lts" "26.3.9.8" "26.3"; do
+          for tag in "26.5.1.882" "26.5.1" "26.5"; do
             if docker pull "clickhouse/clickhouse-server:$tag" 2>/dev/null; then
               echo "Using clickhouse/clickhouse-server:$tag"
               docker create --name ch-extract "clickhouse/clickhouse-server:$tag"

CHANGELOG.md

@@ -4,6 +4,48 @@ All notable changes to `chdb-sqlalchemy` are recorded here.
 The format follows [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and the project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.2.2] — 2026-06-12
+
+Compatibility release for chdb-core 26.5.0 (the ClickHouse 26.5
+baseline), which changed three behaviors that chdb-core 26.3 had and
+turned the nightly CI red from 2026-06-08. All fixes are
+backward-compatible: the cursor coercions are no-ops on chdb-core 26.3
+native values.
+
+### Fixed
+
+- **Composite cells lost numeric typing on chdb-core 26.5** — the new
+  binary serialises Float / Decimal / temporal leaves *inside*
+  `Array` / `Tuple` / `Map` / `Nested` / geo cells as quoted strings
+  (`"['1.5', '2.5']"` for `Array(Float64)`), where 26.3 emitted bare
+  numerics. The cursor wrapper now walks composite cells recursively,
+  driven by the column's ClickHouse type string, and re-coerces leaves
+  to native `float` / `Decimal` / `int` / `date` / `datetime` / `time`.
+  Container shapes are preserved exactly as parsed; named `Tuple`
+  cells (which chdb.dbapi returns as dicts keyed by field name) keep
+  the dict shape with coerced values.
+- **PK reflection returned `['(user_id)']` on ClickHouse 26.5** — the
+  server now preserves wrapping parentheses around a single-column
+  sorting key in `system.tables.sorting_key` (`ORDER BY (user_id)`
+  used to be reported as `user_id`). Reflection strips parens that
+  wrap the entire expression before splitting, so
+  `get_pk_constraint` returns bare column names on both server
+  generations.
+
+### Changed
+
+- **Decimal high-precision lock inverted** — chdb-core 26.5 fixed the
+  double round-trip that lossified `Decimal(P>18)` cells
+  (chdb-io/chdb#574). The torture test that locked the lossy behavior
+  now asserts full-precision round-trip instead.
+- **Float NaN / ±Inf lock inverted** — chdb-core 26.5 fixed the fold
+  to `None` on readback (chdb-io/chdb#575). The torture test now
+  asserts the values come back as real floats.
+- L5 differential reference binary bumped from
+  `clickhouse-server:26.3.9.8-lts` to `clickhouse-server:26.5.1.882`
+  to match the chdb-core 26.5 baseline; the version-skew sanity test
+  guards the pairing.
+
 ## [0.2.1] — 2026-05-21
 
 ### Added