Optimize sys.indexes index_id computation for correlated subquery access

contrib/babelfishpg_tsql/sql/sys_views.sql

@@ -827,15 +827,6 @@ GRANT SELECT ON sys.identity_columns TO PUBLIC;
 
 create or replace view sys.indexes as
 -- Get all indexes from all system and user tables
-with index_id_map as MATERIALIZED(
-  select
-    indexrelid,
-    case
-      when indisclustered then 1
-      else 1+row_number() over(partition by indrelid order by indexrelid)
-    end as index_id
-  from pg_index
-)
 select
   cast(X.indrelid as int) as object_id
   , cast(
@@ -864,9 +855,15 @@ select
   , cast(0 as sys.bit) as has_filter
   , cast(null as sys.nvarchar) as filter_definition
   , cast(0 as sys.bit) as auto_created
-  , cast(imap.index_id as int) as index_id
-from pg_index X 
-inner join index_id_map imap on imap.indexrelid = X.indexrelid
+  , cast(
+    case
+      when X.indisclustered then 1
+      else 2 + (SELECT count(*) FROM pg_index x2
+                WHERE x2.indrelid = X.indrelid
+                AND x2.indexrelid < X.indexrelid)
+    end
+    as int) as index_id
+from pg_index X
 inner join pg_class I on I.oid = X.indexrelid
 inner join pg_class ptbl on ptbl.oid = X.indrelid and ptbl.relispartition = false
 inner join pg_namespace nsp on nsp.oid = I.relnamespace

contrib/babelfishpg_tsql/sql/upgrades/babelfishpg_tsql--6.1.0--6.2.0.sql

@@ -208,6 +208,98 @@ CREATE OR REPLACE AGGREGATE sys.tsql_select_for_xml_text_agg(
     FINALFUNC = tsql_query_to_xml_text_ffunc
 );
 
+create or replace view sys.indexes as
+-- Get all indexes from all system and user tables
+select
+  cast(X.indrelid as int) as object_id
+  , cast(
+		coalesce(
+			(select pg_catalog.string_agg(
+				case
+					when option like 'bbf_original_rel_name=%' then substring(option, 23 /* prefix length */)
+					else null
+				end, ',')
+			from unnest(I.reloptions) as option),
+			I.relname)
+		AS sys.sysname) AS name
+  , cast(case when X.indisclustered then 1 else 2 end as sys.tinyint) as type
+  , cast(case when X.indisclustered then 'CLUSTERED' else 'NONCLUSTERED' end as sys.nvarchar(60)) as type_desc
+  , cast(X.indisunique as sys.bit) as is_unique
+  , cast(case when ps.scheme_id is null then 1 else ps.scheme_id end as int) as data_space_id
+  , cast(0 as sys.bit) as ignore_dup_key
+  , cast(X.indisprimary as sys.bit) as is_primary_key
+  , cast(case when const.oid is null then 0 else 1 end as sys.bit) as is_unique_constraint
+  , cast(0 as sys.tinyint) as fill_factor
+  , cast(case when X.indpred is null then 0 else 1 end as sys.bit) as is_padded
+  , cast(case when X.indisready then 0 else 1 end as sys.bit) as is_disabled
+  , cast(0 as sys.bit) as is_hypothetical
+  , cast(1 as sys.bit) as allow_row_locks
+  , cast(1 as sys.bit) as allow_page_locks
+  , cast(0 as sys.bit) as has_filter
+  , cast(null as sys.nvarchar) as filter_definition
+  , cast(0 as sys.bit) as auto_created
+  , cast(
+    case
+      when X.indisclustered then 1
+      else 2 + (SELECT count(*) FROM pg_index x2
+                WHERE x2.indrelid = X.indrelid
+                AND x2.indexrelid < X.indexrelid)
+    end
+    as int) as index_id
+from pg_index X
+inner join pg_class I on I.oid = X.indexrelid
+inner join pg_class ptbl on ptbl.oid = X.indrelid and ptbl.relispartition = false
+inner join pg_namespace nsp on nsp.oid = I.relnamespace
+left join sys.babelfish_namespace_ext ext on (nsp.nspname = ext.nspname and ext.dbid = sys.db_id())
+left join sys.babelfish_partition_depend pd on
+  (ext.orig_name  = pd.schema_name COLLATE sys.database_default
+   and CAST(ptbl.relname AS sys.nvarchar(128)) = pd.table_name COLLATE sys.database_default and pd.dbid = sys.db_id() and ptbl.relkind = 'p')
+left join sys.babelfish_partition_scheme ps on (ps.partition_scheme_name = pd.partition_scheme_name and ps.dbid = sys.db_id())
+-- check if index is a unique constraint
+left join pg_constraint const on const.conindid = I.oid and const.contype = 'u'
+where 
+-- index is active
+X.indislive 
+-- filter to get all the objects that belong to sys or babelfish schemas
+and (nsp.nspname = 'sys' or ext.nspname is not null)
+
+union all 
+-- Create HEAP entries for each system and user table
+select
+  cast(t.oid as int) as object_id
+  , cast(null as sys.sysname) as name
+  , cast(0 as sys.tinyint) as type
+  , cast('HEAP' as sys.nvarchar(60)) as type_desc
+  , cast(0 as sys.bit) as is_unique
+  , cast(case when ps.scheme_id is null then 1 else ps.scheme_id end as int) as data_space_id
+  , cast(0 as sys.bit) as ignore_dup_key
+  , cast(0 as sys.bit) as is_primary_key
+  , cast(0 as sys.bit) as is_unique_constraint
+  , cast(0 as sys.tinyint) as fill_factor
+  , cast(0 as sys.bit) as is_padded
+  , cast(0 as sys.bit) as is_disabled
+  , cast(0 as sys.bit) as is_hypothetical
+  , cast(1 as sys.bit) as allow_row_locks
+  , cast(1 as sys.bit) as allow_page_locks
+  , cast(0 as sys.bit) as has_filter
+  , cast(null as sys.nvarchar) as filter_definition
+  , cast(0 as sys.bit) as auto_created
+  , cast(0 as int) as index_id
+from pg_class t
+inner join pg_namespace nsp on nsp.oid = t.relnamespace
+left join sys.babelfish_namespace_ext ext on (nsp.nspname = ext.nspname and ext.dbid = sys.db_id())
+left join sys.babelfish_partition_depend pd on
+  (ext.orig_name = pd.schema_name COLLATE sys.database_default
+   and CAST(t.relname AS sys.nvarchar(128)) = pd.table_name COLLATE sys.database_default and pd.dbid = sys.db_id())
+left join sys.babelfish_partition_scheme ps on (ps.partition_scheme_name = pd.partition_scheme_name and ps.dbid = sys.db_id())
+where (t.relkind = 'r' or t.relkind = 'p')
+and t.relispartition = false
+-- filter to get all the objects that belong to sys or babelfish schemas
+and (nsp.nspname = 'sys' or ext.nspname is not null)
+and has_table_privilege(t.oid, 'SELECT,INSERT,UPDATE,DELETE,TRUNCATE,TRIGGER')
+order by object_id, type_desc;
+GRANT SELECT ON sys.indexes TO PUBLIC;
+
 -- Drops the temporary procedure used by the upgrade script.
 -- Please have this be one of the last statements executed in this upgrade script.
 DROP PROCEDURE sys.babelfish_drop_deprecated_object(varchar, varchar, varchar, varchar);