Generate gp_ view for desired pg_ system views

For a selected list of PG system views (started with 'pg_'prefix ), we
will create a corresponding 'gp_' view for each one in the list.
Each 'gp_' view is basically a UNION ALL of the results of running the
corresponding 'pg_' view on all segments (including the coordinator).

Note that, these views do not aggregate the results. The aggregate
version of the views will be named with a '_summary' appendix (such
as 'gp_stat_all_tables_summary').

To add a new 'pg_' view to this list, simply put the name in file
'src/backend/catalog/system_views_gp.in'. This commit adds an initial
list of views that we think make sense to have 'gp_' views.

With this change, we also remove the existing definition of
gp_stat_archiver view and let it be generated automatically.
We also had gp_stat_replication but it carries additional column than
pg_stat_replication so it cannot use the automatic way.

Author: huansong

src/backend/catalog/.gitignore

@@ -8,3 +8,4 @@
 /pg_*_d.h
 /gp_*_d.h
 /bki-stamp
+/system_views_gp.sql

src/backend/catalog/Makefile

@@ -56,6 +56,9 @@ OBJS += pg_extprotocol.o \
 	   gp_matview_aux.o \
        pg_directory_table.o storage_directory_table.o
 
+GP_SYSVIEW_IN = system_views_gp.in
+GP_SYSVIEW_SQL = system_views_gp.sql
+
 CATALOG_JSON:= $(addprefix $(top_srcdir)/gpMgmt/bin/gppylib/data/, $(addsuffix .json,$(GP_MAJORVERSION)))
 
 include $(top_srcdir)/src/backend/common.mk
@@ -133,7 +136,7 @@ POSTGRES_BKI_DATA += $(addprefix $(top_srcdir)/src/include/catalog/,\
 	$(top_builddir)/src/include/catalog/gp_version_at_initdb.dat
 
 
-all: distprep generated-header-symlinks
+all: distprep generated-header-symlinks $(GP_SYSVIEW_SQL)
 
 distprep: bki-stamp
 
@@ -197,6 +200,7 @@ ifeq ($(USE_INTERNAL_FTS_FOUND), false)
 endif
 	$(INSTALL_DATA) $(srcdir)/system_functions.sql '$(DESTDIR)$(datadir)/system_functions.sql'
 	$(INSTALL_DATA) $(srcdir)/system_views.sql '$(DESTDIR)$(datadir)/system_views.sql'
+	$(INSTALL_DATA) $(srcdir)/$(GP_SYSVIEW_SQL) '$(DESTDIR)$(datadir)/$(GP_SYSVIEW_SQL)'
 	$(INSTALL_DATA) $(srcdir)/information_schema.sql '$(DESTDIR)$(datadir)/information_schema.sql'
 	$(INSTALL_DATA) $(call vpathsearch,cdb_schema.sql) '$(DESTDIR)$(datadir)/cdb_init.d/cdb_schema.sql'
 	$(INSTALL_DATA) $(srcdir)/sql_features.txt '$(DESTDIR)$(datadir)/sql_features.txt'
@@ -216,4 +220,4 @@ endif
 clean:
 
 maintainer-clean: clean
-	rm -f bki-stamp postgres.bki system_constraints.sql $(GENERATED_HEADERS)
+	rm -f bki-stamp postgres.bki system_constraints.sql $(GENERATED_HEADERS) $(GP_SYSVIEW_SQL)

src/backend/catalog/system_views.sql

@@ -1098,6 +1098,7 @@ $$
 $$
 LANGUAGE SQL EXECUTE ON ALL SEGMENTS;
 
+-- This view has an additional column than pg_stat_replication so cannot be generated using system_views_gp.in
 CREATE VIEW gp_stat_replication AS
     SELECT *, pg_catalog.gp_replication_error() AS sync_error
     FROM pg_catalog.gp_stat_get_master_replication() AS R
@@ -1805,11 +1806,6 @@ UNION ALL
   SELECT gp_segment_id, gp_get_suboverflowed_backends() FROM gp_dist_random('gp_id') order by 1;
 
 
-CREATE OR REPLACE VIEW gp_stat_archiver AS
-    SELECT -1 AS gp_segment_id, * FROM pg_stat_archiver
-    UNION
-    SELECT gp_execution_segment() AS gp_segment_id, * FROM gp_dist_random('pg_stat_archiver');
-
 CREATE FUNCTION gp_get_session_endpoints (OUT gp_segment_id int, OUT auth_token text,
 									  OUT cursorname text, OUT sessionid int, OUT hostname varchar(64),
 									  OUT port int, OUT username text, OUT state text,

src/backend/catalog/system_views_gp.in

@@ -0,0 +1,48 @@
+# This file lists all the PG system views 'pg_%' that we would like to create an
+# MPP-aware view 'gp_%' out of. The generated 'gp_%' view definitions will be placed
+# in system_views_gp.sql, and initialized at the same time as system_views.sql.
+pg_backend_memory_contexts
+pg_config
+pg_cursors
+pg_file_settings
+pg_replication_origin_status
+pg_replication_slots
+pg_settings
+pg_stat_activity
+pg_stat_archiver
+pg_stat_bgwriter
+pg_stat_database
+pg_stat_database_conflicts
+pg_stat_gssapi
+pg_stat_operations
+pg_stat_progress_analyze
+pg_stat_progress_basebackup
+pg_stat_progress_cluster
+pg_stat_progress_copy
+pg_stat_progress_create_index
+pg_stat_progress_vacuum
+pg_stat_slru
+pg_stat_ssl
+pg_stat_subscription
+pg_stat_sys_indexes
+pg_stat_sys_tables
+pg_stat_user_functions
+pg_stat_user_indexes
+pg_stat_user_tables
+pg_stat_wal
+pg_stat_wal_receiver
+pg_stat_xact_all_tables
+pg_stat_xact_sys_tables
+pg_stat_xact_user_functions
+pg_stat_xact_user_tables
+pg_statio_all_indexes
+pg_statio_all_sequences
+pg_statio_all_tables
+pg_statio_sys_indexes
+pg_statio_sys_sequences
+pg_statio_sys_tables
+pg_statio_user_indexes
+pg_statio_user_sequences
+pg_statio_user_tables
+pg_stats
+pg_stats_ext

src/bin/initdb/initdb.c

@@ -174,6 +174,7 @@ static char *external_fts_files;
 #endif
 static char *system_functions_file;
 static char *system_views_file;
+static char *system_views_gp_file;
 static bool success = false;
 static bool made_new_pgdata = false;
 static bool found_existing_pgdata = false;
@@ -2831,6 +2832,7 @@ setup_data_file_paths(void)
 	set_input(&system_constraints_file, "system_constraints.sql");
 	set_input(&system_functions_file, "system_functions.sql");
 	set_input(&system_views_file, "system_views.sql");
+	set_input(&system_views_gp_file, "system_views_gp.sql");
 
 	set_input(&cdb_init_d_dir, "cdb_init.d");
 
@@ -2864,6 +2866,7 @@ setup_data_file_paths(void)
 #endif
 	check_input(system_functions_file);
 	check_input(system_views_file);
+	check_input(system_views_gp_file);
 }
 
 
@@ -3231,6 +3234,7 @@ initialize_data_directory(void)
 	 */
 
 	setup_run_file(cmdfd, system_views_file);
+	setup_run_file(cmdfd, system_views_gp_file);
 
 	setup_description(cmdfd);
 

src/include/catalog/catversion.h

@@ -56,6 +56,6 @@
  */
 
 /*							3yyymmddN */
-#define CATALOG_VERSION_NO	302502091
+#define CATALOG_VERSION_NO	302506101
 
 #endif