Don't DROP timescaledb_information VIEWS in migrations

update/downgrade scripts detach information views during ALTER
EXTENSION so they must not be dropped to allow users to have
references on them.

Author: svenklemm

sql/updates/latest-dev.sql

@@ -72,8 +72,6 @@ CREATE TABLE _timescaledb_internal.tmp_dimension_slice_seq_value AS
 ALTER TABLE _timescaledb_catalog.chunk_constraint
     DROP CONSTRAINT IF EXISTS chunk_constraint_dimension_slice_id_fkey;
 
-DROP VIEW IF EXISTS timescaledb_information.chunks;
-
 ALTER EXTENSION timescaledb DROP TABLE _timescaledb_catalog.dimension_slice;
 ALTER EXTENSION timescaledb DROP SEQUENCE _timescaledb_catalog.dimension_slice_id_seq;
 
@@ -163,7 +161,6 @@ DROP FUNCTION _timescaledb_functions.chunk_constraint_add_table_constraint(
     _timescaledb_catalog.chunk_constraint);
 DROP FUNCTION IF EXISTS _timescaledb_internal.chunk_constraint_add_table_constraint(
     _timescaledb_catalog.chunk_constraint);
-DROP VIEW IF EXISTS timescaledb_information.chunks;
 
 ALTER EXTENSION timescaledb DROP TABLE _timescaledb_catalog.chunk_constraint;
 ALTER EXTENSION timescaledb DROP SEQUENCE _timescaledb_catalog.chunk_constraint_name;
@@ -187,9 +184,6 @@ ALTER TABLE _timescaledb_catalog.hypertable
 
 -- Drop views and foreign keys that depend on the catalog table.
 DROP VIEW IF EXISTS timescaledb_experimental.policies;
-DROP VIEW IF EXISTS timescaledb_information.hypertables;
-DROP VIEW IF EXISTS timescaledb_information.continuous_aggregates;
-DROP VIEW IF EXISTS timescaledb_information.jobs;
 
 ALTER TABLE _timescaledb_catalog.continuous_aggs_watermark
     DROP CONSTRAINT continuous_aggs_watermark_mat_hypertable_id_fkey;

sql/updates/reverse-dev.sql

@@ -42,7 +42,6 @@ WHERE c.osm_chunk
 ON CONFLICT DO NOTHING;
 
 -- Drop chunk stats related objects
-DROP VIEW IF EXISTS timescaledb_information.stat_chunk_activity;
 DROP FUNCTION IF EXISTS _timescaledb_functions.chunk_statistics(regclass, regclass, timestamptz);
 DROP FUNCTION IF EXISTS _timescaledb_functions.chunk_statistics_reset();
 
@@ -91,8 +90,6 @@ CREATE TABLE _timescaledb_internal.tmp_dimension_slice AS
 CREATE TABLE _timescaledb_internal.tmp_dimension_slice_seq_value AS
     SELECT last_value, is_called FROM _timescaledb_catalog.dimension_slice_id_seq;
 
-DROP VIEW IF EXISTS timescaledb_information.chunks;
-
 ALTER EXTENSION timescaledb DROP TABLE _timescaledb_catalog.dimension_slice;
 ALTER EXTENSION timescaledb DROP SEQUENCE _timescaledb_catalog.dimension_slice_id_seq;
 
@@ -193,9 +190,6 @@ DROP FUNCTION IF EXISTS _timescaledb_functions.rebuild_sparse_index(REGCLASS, BO
 -- Rebuild the catalog table `_timescaledb_catalog.continuous_agg` to drop the
 -- `schema_change_timestamp` column.
 DROP VIEW IF EXISTS timescaledb_experimental.policies;
-DROP VIEW IF EXISTS timescaledb_information.hypertables;
-DROP VIEW IF EXISTS timescaledb_information.continuous_aggregates;
-DROP VIEW IF EXISTS timescaledb_information.jobs;
 
 ALTER TABLE _timescaledb_catalog.continuous_aggs_watermark
     DROP CONSTRAINT continuous_aggs_watermark_mat_hypertable_id_fkey;