Limit postgres_indexes to owned schemas

Relates to https://gitlab.com/gitlab-org/gitlab/-/issues/254995

changelogs/unreleased/ab-reindexing-limit-schema.yml

+---
+title: Limit postgres_indexes to owned schemas
+merge_request: 43834
+author:
+type: other

db/migrate/20200930094812_update_postgres_indexes_view.rb

+# frozen_string_literal: true
+
+class UpdatePostgresIndexesView < ActiveRecord::Migration[6.0]
+  DOWNTIME = false
+
+  def up
+    execute(<<~SQL)
+      CREATE OR REPLACE VIEW postgres_indexes AS
+      SELECT
+        pg_namespace.nspname || '.' || pg_class.relname as identifier,
+        pg_index.indexrelid,
+        pg_namespace.nspname as schema,
+        pg_class.relname as name,
+        pg_index.indisunique as unique,
+        pg_index.indisvalid as valid_index,
+        pg_class.relispartition as partitioned,
+        pg_index.indisexclusion as exclusion,
+        pg_indexes.indexdef as definition,
+        pg_relation_size(pg_class.oid) as ondisk_size_bytes
+      FROM pg_index
+      INNER JOIN pg_class ON pg_class.oid = pg_index.indexrelid
+      INNER JOIN pg_namespace ON pg_class.relnamespace = pg_namespace.oid
+      INNER JOIN pg_indexes ON pg_class.relname = pg_indexes.indexname
+      WHERE pg_namespace.nspname <> 'pg_catalog'
+        AND pg_namespace.nspname IN (
+          current_schema(),
+          'gitlab_partitions_dynamic',
+          'gitlab_partitions_static'
+        )
+    SQL
+  end
+
+  def down
+    execute(<<~SQL)
+      CREATE OR REPLACE VIEW postgres_indexes AS
+      SELECT
+        pg_namespace.nspname || '.' || pg_class.relname as identifier,
+        pg_index.indexrelid,
+        pg_namespace.nspname as schema,
+        pg_class.relname as name,
+        pg_index.indisunique as unique,
+        pg_index.indisvalid as valid_index,
+        pg_class.relispartition as partitioned,
+        pg_index.indisexclusion as exclusion,
+        pg_indexes.indexdef as definition,
+        pg_relation_size(pg_class.oid) as ondisk_size_bytes
+      FROM pg_index
+      INNER JOIN pg_class ON pg_class.oid = pg_index.indexrelid
+      INNER JOIN pg_namespace ON pg_class.relnamespace = pg_namespace.oid
+      INNER JOIN pg_indexes ON pg_class.relname = pg_indexes.indexname
+      WHERE pg_namespace.nspname <> 'pg_catalog'
+    SQL
+  end
+end

db/schema_migrations/20200930094812

+b92b48a17bfd350a70017bfee99bcfb3dbc5ae9e33c8f23ab593666e5c3900aa
\ No newline at end of file

db/structure.sql

@@ -14428,7 +14428,7 @@ CREATE VIEW postgres_indexes AS
      JOIN pg_class ON ((pg_class.oid = pg_index.indexrelid)))
      JOIN pg_namespace ON ((pg_class.relnamespace = pg_namespace.oid)))
      JOIN pg_indexes ON ((pg_class.relname = pg_indexes.indexname)))
-  WHERE (pg_namespace.nspname <> 'pg_catalog'::name);
+  WHERE ((pg_namespace.nspname <> 'pg_catalog'::name) AND (pg_namespace.nspname = ANY (ARRAY["current_schema"(), 'gitlab_partitions_dynamic'::name, 'gitlab_partitions_static'::name])));
 
 CREATE TABLE postgres_reindex_actions (
     id bigint NOT NULL,