Fix dump/restore when chunk skipping is enabled

.unreleased/pr_8211

@@ -0,0 +1 @@
+Fixes: #8211 Fix dump/restore when chunk skipping is enabled

scripts/test_update_from_version.sh

@@ -12,7 +12,7 @@ FROM_VERSION=${FROM_VERSION:-$(grep '^previous_version ' version.config | awk '{
 TO_VERSION=${TO_VERSION:-$(grep '^version ' version.config | awk '{ print $3 }')}
 
 TEST_REPAIR=${TEST_REPAIR:-false}
-TEST_VERSION=${TEST_VERSION:-v8}
+TEST_VERSION=${TEST_VERSION:-v9}
 
 OUTPUT_DIR=${OUTPUT_DIR:-update_test/${FROM_VERSION}_to_${TO_VERSION}}
 PGDATA="${OUTPUT_DIR}/data"
@@ -135,5 +135,3 @@ if [ -f "${OUTPUT_DIR}/baseline_vs_updated.diff" ] || [ -f "${OUTPUT_DIR}/baseli
   echo "Update test for ${FROM_VERSION} -> ${TO_VERSION} failed"
   exit 1
 fi
-
-

scripts/test_updates.sh

@@ -87,14 +87,19 @@ if [ -n "${VERSIONS}" ]; then
   for version in ${VERSIONS}; do
     ts_minor_version=$(echo "${version}" | awk -F. '{print $2}')
 
-    TEST_VERSION=v8
-
     if [ "${ts_minor_version}" -ge 10 ]; then
       TEST_REPAIR=true
     else
       TEST_REPAIR=false
     fi
 
+
+    if [ "${ts_minor_version}" -ge 16 ]; then
+        TEST_VERSION=v9
+    else
+        TEST_VERSION=v8
+    fi
+
     export TEST_VERSION TEST_REPAIR
 
     FROM_VERSION=${version} "${SCRIPT_DIR}/test_update_from_version.sh"
@@ -115,4 +120,3 @@ else
 fi
 
 exit $FAIL_COUNT
-

sql/pre_install/tables.sql

@@ -230,7 +230,7 @@ SELECT pg_catalog.pg_extension_config_dump('_timescaledb_catalog.chunk_index', '
 CREATE TABLE _timescaledb_catalog.chunk_column_stats (
   id serial NOT NULL,
   hypertable_id integer NOT NULL,
-  chunk_id integer NOT NULL,
+  chunk_id integer NULL,
   column_name name NOT NULL,
   range_start bigint NOT NULL,
   range_end bigint NOT NULL,

sql/updates/latest-dev.sql

@@ -39,4 +39,10 @@ AS $$
 BEGIN
   -- empty body
 END;
-$$ LANGUAGE PLPGSQL;
+$$ LANGUAGE PLPGSQL;
+
+-- Make chunk_id use NULL to mark special entries instead of 0
+-- (Invalid chunk) since that doesn't work with the FK constraint on
+-- chunk_id.
+ALTER TABLE _timescaledb_catalog.chunk_column_stats ALTER COLUMN chunk_id DROP NOT NULL;
+UPDATE _timescaledb_catalog.chunk_column_stats SET chunk_id = NULL WHERE chunk_id = 0;

sql/updates/reverse-dev.sql

@@ -23,3 +23,12 @@ BEGIN
   -- empty body
 END;
 $$ LANGUAGE PLPGSQL;
+
+-- Add back the chunk_column_stats NOT NULL constraint. But first
+-- delete all entries with with NULL since they will no longer be
+-- allowed. Note that it is not possible to revert chunk_id back to 0
+-- because it will violate the FK constraint. Removing the entries
+-- effectively means that collecting column stats for those columns
+-- will be disabled. It can be enabled again after downgrade.
+DELETE FROM _timescaledb_catalog.chunk_column_stats WHERE chunk_id IS NULL;
+ALTER TABLE _timescaledb_catalog.chunk_column_stats ALTER COLUMN chunk_id SET NOT NULL;