test(query): verify persisted AVG1 state compatibility

Signed-off-by: discord9 <discord9@163.com>

tests/compatibility/cases/avg_state_binary/case.toml

@@ -0,0 +1,9 @@
+name = "avg_state_binary"
+reason = "Verify persisted AVG1 binary states are decoded, merged, and reproduced exactly after upgrade."
+introduced_by = "PR #9035"
+topologies = ["distributed", "standalone"]
+from_range = ["*"]
+to_range = [">=v1.3.0-alpha.1"]
+features = ["table", "query", "aggregate"]
+owner = "query"
+namespace = "avg_state_binary"

tests/compatibility/cases/avg_state_binary/setup.sql

@@ -0,0 +1,14 @@
+CREATE TABLE avg1_states (
+  seq_id INT PRIMARY KEY,
+  state BINARY,
+  ts TIMESTAMP TIME INDEX
+);
+
+-- AVG1: magic (4 bytes), little-endian u64 count, little-endian f64 sum.
+INSERT INTO avg1_states (seq_id, state, ts) VALUES
+  (1, X'4156473102000000000000000000000000000840', '2026-01-01 00:00:00'),
+  (2, X'4156473101000000000000000000000000001840', '2026-01-01 00:00:01'),
+  (3, NULL, '2026-01-01 00:00:02'),
+  (4, X'4156473100000000000000000000000000000000', '2026-01-01 00:00:03');
+
+ADMIN FLUSH_TABLE('avg1_states');

tests/compatibility/cases/avg_state_binary/verify.result

@@ -0,0 +1,36 @@
+-- The persisted states have counts 2 and 1 and sums 3.0 and 6.0.
+-- Null and canonical empty states do not change the merged AVG1 state.
+SELECT avg_merge(state) = X'4156473103000000000000000000000000002240' AS merged_state_matches
+FROM avg1_states;
+
++----------------------+
+| merged_state_matches |
++----------------------+
+| true                 |
++----------------------+
+
+-- A new state over the equivalent Float64 values has the exact same AVG1 bytes.
+WITH generated_values AS (
+  SELECT CAST(1.0 AS DOUBLE) AS value
+  UNION ALL SELECT CAST(2.0 AS DOUBLE)
+  UNION ALL SELECT CAST(6.0 AS DOUBLE)
+)
+SELECT avg_state(value) = X'4156473103000000000000000000000000002240' AS generated_state_matches
+FROM generated_values;
+
++-------------------------+
+| generated_state_matches |
++-------------------------+
+| true                    |
++-------------------------+
+
+-- A null-only merge is the canonical empty AVG1 state.
+SELECT avg_merge(state) = X'4156473100000000000000000000000000000000' AS null_state_is_empty
+FROM avg1_states
+WHERE state IS NULL;
+
++---------------------+
+| null_state_is_empty |
++---------------------+
+| true                |
++---------------------+

tests/compatibility/cases/avg_state_binary/verify.sql

@@ -0,0 +1,18 @@
+-- The persisted states have counts 2 and 1 and sums 3.0 and 6.0.
+-- Null and canonical empty states do not change the merged AVG1 state.
+SELECT avg_merge(state) = X'4156473103000000000000000000000000002240' AS merged_state_matches
+FROM avg1_states;
+
+-- A new state over the equivalent Float64 values has the exact same AVG1 bytes.
+WITH generated_values AS (
+  SELECT CAST(1.0 AS DOUBLE) AS value
+  UNION ALL SELECT CAST(2.0 AS DOUBLE)
+  UNION ALL SELECT CAST(6.0 AS DOUBLE)
+)
+SELECT avg_state(value) = X'4156473103000000000000000000000000002240' AS generated_state_matches
+FROM generated_values;
+
+-- A null-only merge is the canonical empty AVG1 state.
+SELECT avg_merge(state) = X'4156473100000000000000000000000000000000' AS null_state_is_empty
+FROM avg1_states
+WHERE state IS NULL;