chore: import upstream snapshot with attribution

bootstrap/sql/migrations/native/1.12.9/postgres/schemaChanges.sql

@@ -0,0 +1,62 @@
+-- Boost memory for the dedup + index build. RESET at end.
+SET work_mem = '256MB';
+SET maintenance_work_mem = '512MB';
+
+-- Dedup before the unique index rebuild. NULL filter on operation: Postgres
+-- UNIQUE treats NULLs as DISTINCT, so the constraint never blocked tableProfile
+-- / columnProfile rows (operation = NULL). GROUP BY treats NULLs as equal —
+-- without the filter we'd collapse rows the constraint never rejected.
+DELETE FROM profiler_data_time_series p
+USING (
+  SELECT entityFQNHash, extension, operation, "timestamp", MAX(ctid) AS keep_ctid
+  FROM profiler_data_time_series
+  WHERE operation IS NOT NULL
+    AND entityFQNHash IS NOT NULL
+  GROUP BY entityFQNHash, extension, operation, "timestamp"
+  HAVING COUNT(*) > 1
+) d
+WHERE p.entityFQNHash = d.entityFQNHash
+  AND p.extension     = d.extension
+  AND p.operation     = d.operation
+  AND p."timestamp"   = d."timestamp"
+  AND p.ctid <> d.keep_ctid;
+
+-- Recover from a prior failed CREATE UNIQUE INDEX CONCURRENTLY: drop the
+-- invalid leftover and rebuild inline so ALTER below can promote it.
+DO $$
+DECLARE
+  invalid_idx oid;
+BEGIN
+  SELECT i.indexrelid INTO invalid_idx
+  FROM pg_index i
+  JOIN pg_class idx ON idx.oid = i.indexrelid
+  WHERE idx.relname = 'profiler_data_time_series_unique_hash_extension_ts'
+    AND i.indrelid = 'profiler_data_time_series'::regclass
+    AND NOT i.indisvalid;
+
+  IF invalid_idx IS NOT NULL THEN
+    EXECUTE 'DROP INDEX ' || invalid_idx::regclass;
+    EXECUTE 'CREATE UNIQUE INDEX profiler_data_time_series_unique_hash_extension_ts '
+         || 'ON profiler_data_time_series '
+         || '(entityFQNHash, extension, operation, "timestamp")';
+  END IF;
+END $$;
+
+-- Restore the unique constraint dropped in 1.9.9. Closes the 1.9.9 regression that caused
+-- /columns?fields=profile 504s, and brings Postgres back in line with MySQL (which never
+-- lost it). The leading (entityFQNHash, extension) prefix serves the column-profile batch query.
+-- Two-phase: CONCURRENTLY build avoids ACCESS EXCLUSIVE lock; ADD CONSTRAINT USING INDEX
+-- promotes the built index without re-scanning.
+CREATE UNIQUE INDEX CONCURRENTLY IF NOT EXISTS
+    profiler_data_time_series_unique_hash_extension_ts
+    ON profiler_data_time_series (entityFQNHash, extension, operation, timestamp);
+
+ALTER TABLE profiler_data_time_series
+    ADD CONSTRAINT profiler_data_time_series_unique_hash_extension_ts
+    UNIQUE USING INDEX profiler_data_time_series_unique_hash_extension_ts;
+
+ANALYZE profiler_data_time_series;
+
+-- Reset session memory before the connection returns to the pool.
+RESET work_mem;
+RESET maintenance_work_mem;