Add gp summary system views

These summary views offer basic aggregation of the gp_stat_* views across Greenplum coordinator and
segments.

Aggregation logic applied as follows:
* Time related (last_%): use max()
* Transaction related, not innately summable (number of commits/rollbacks) : use max()
* Table specific: sum()/numsegments for replicated tables, sum() for
  distributed tables
* Innately summable stats, if no particular table is involved: use sum()
* pid: use coordinator's pid (not used here, but this is the convention in other gp_%_summary views)

Author: AJR-VMware

src/backend/catalog/system_views.sql

@@ -710,87 +710,6 @@ CREATE VIEW pg_stat_all_tables_internal AS
     WHERE C.relkind IN ('r', 't', 'm', 'o', 'b', 'M', 'p')
     GROUP BY C.oid, N.nspname, C.relname;
 
--- Gather data from segments on user tables, and use data on coordinator on system tables.
-
-CREATE VIEW pg_stat_all_tables AS
-SELECT
-    s.relid,
-    s.schemaname,
-    s.relname,
-    m.seq_scan,
-    m.last_seq_scan,
-    m.seq_tup_read,
-    m.idx_scan,
-    m.last_idx_scan,
-    m.idx_tup_fetch,
-    m.n_tup_ins,
-    m.n_tup_upd,
-    m.n_tup_del,
-    m.n_tup_hot_upd,
-    m.n_tup_newpage_upd,
-    m.n_live_tup,
-    m.n_dead_tup,
-    m.n_mod_since_analyze,
-    m.n_ins_since_vacuum,
-    s.last_vacuum,
-    s.last_autovacuum,
-    s.last_analyze,
-    s.last_autoanalyze,
-    s.vacuum_count,
-    s.autovacuum_count,
-    s.analyze_count,
-    s.autoanalyze_count
-FROM
-    (SELECT
-         allt.relid,
-         allt.schemaname,
-         allt.relname,
-         case when d.policytype = 'r' then (sum(seq_scan)/d.numsegments)::bigint else sum(seq_scan) end seq_scan,
-         max(last_seq_scan) as last_seq_scan,
-         case when d.policytype = 'r' then (sum(seq_tup_read)/d.numsegments)::bigint else sum(seq_tup_read) end seq_tup_read,
-         case when d.policytype = 'r' then (sum(idx_scan)/d.numsegments)::bigint else sum(idx_scan) end idx_scan,
-         max(last_idx_scan) as last_idx_scan,
-         case when d.policytype = 'r' then (sum(idx_tup_fetch)/d.numsegments)::bigint else sum(idx_tup_fetch) end idx_tup_fetch,
-         case when d.policytype = 'r' then (sum(n_tup_ins)/d.numsegments)::bigint else sum(n_tup_ins) end n_tup_ins,
-         case when d.policytype = 'r' then (sum(n_tup_upd)/d.numsegments)::bigint else sum(n_tup_upd) end n_tup_upd,
-         case when d.policytype = 'r' then (sum(n_tup_del)/d.numsegments)::bigint else sum(n_tup_del) end n_tup_del,
-         case when d.policytype = 'r' then (sum(n_tup_hot_upd)/d.numsegments)::bigint else sum(n_tup_hot_upd) end n_tup_hot_upd,
-         max(n_tup_newpage_upd) as n_tup_newpage_upd,
-         case when d.policytype = 'r' then (sum(n_live_tup)/d.numsegments)::bigint else sum(n_live_tup) end n_live_tup,
-         case when d.policytype = 'r' then (sum(n_dead_tup)/d.numsegments)::bigint else sum(n_dead_tup) end n_dead_tup,
-         case when d.policytype = 'r' then (sum(n_mod_since_analyze)/d.numsegments)::bigint else sum(n_mod_since_analyze) end n_mod_since_analyze,
-         case when d.policytype = 'r' then (sum(n_ins_since_vacuum)/d.numsegments)::bigint else sum(n_ins_since_vacuum) end n_ins_since_vacuum,
-         max(last_vacuum) as last_vacuum,
-         max(last_autovacuum) as last_autovacuum,
-         max(last_analyze) as last_analyze,
-         max(last_autoanalyze) as last_autoanalyze,
-         max(vacuum_count) as vacuum_count,
-         max(autovacuum_count) as autovacuum_count,
-         max(analyze_count) as analyze_count,
-         max(autoanalyze_count) as autoanalyze_count
-     FROM
-         gp_dist_random('pg_stat_all_tables_internal') allt
-         inner join pg_class c
-               on allt.relid = c.oid
-         left outer join gp_distribution_policy d
-              on allt.relid = d.localoid
-     WHERE
-        relid >= 16384
-        and (
-            d.localoid is not null
-            or c.relkind in ('o', 'b', 'M')
-            )
-     GROUP BY allt.relid, allt.schemaname, allt.relname, d.policytype, d.numsegments
-
-     UNION ALL
-
-     SELECT
-         *
-     FROM
-         pg_stat_all_tables_internal
-     WHERE
-             relid < 16384) m, pg_stat_all_tables_internal s
-WHERE m.relid = s.relid;
 
 CREATE VIEW pg_stat_xact_all_tables AS
     SELECT
@@ -822,7 +741,7 @@ CREATE VIEW pg_stat_sys_tables AS
 -- since we don't have segments.
 -- We create a new view for single node mode.
 CREATE VIEW pg_stat_sys_tables_single_node AS
-    SELECT * FROM pg_stat_all_tables_internal
+    SELECT * FROM pg_stat_all_tables
     WHERE schemaname IN ('pg_catalog', 'information_schema') OR
           schemaname ~ '^pg_toast';
 
@@ -840,7 +759,7 @@ CREATE VIEW pg_stat_user_tables AS
 -- since we don't have segments.
 -- We create a new view for single node mode.
 CREATE VIEW pg_stat_user_tables_single_node AS
-    SELECT * FROM pg_stat_all_tables_internal
+    SELECT * FROM pg_stat_all_tables
     WHERE schemaname NOT IN ('pg_catalog', 'information_schema') AND
           schemaname !~ '^pg_toast';
 
@@ -910,45 +829,6 @@ CREATE VIEW pg_stat_all_indexes_internal AS
             LEFT JOIN pg_namespace N ON (N.oid = C.relnamespace)
     WHERE C.relkind IN ('r', 't', 'm', 'o', 'b', 'M');
 
--- Gather data from segments on user tables, and use data on coordinator on system tables.
-
-CREATE VIEW pg_stat_all_indexes AS
-SELECT
-    s.relid,
-    s.indexrelid,
-    s.schemaname,
-    s.relname,
-    s.indexrelname,
-    m.idx_scan,
-    m.last_idx_scan,
-    m.idx_tup_read,
-    m.idx_tup_fetch
-FROM
-    (SELECT
-         relid,
-         indexrelid,
-         schemaname,
-         relname,
-         indexrelname,
-         sum(idx_scan) as idx_scan,
-         max(last_idx_scan) as last_idx_scan,
-         sum(idx_tup_read) as idx_tup_read,
-         sum(idx_tup_fetch) as idx_tup_fetch
-     FROM
-         gp_dist_random('pg_stat_all_indexes_internal')
-     WHERE
-             relid >= 16384
-     GROUP BY relid, indexrelid, schemaname, relname, indexrelname
-
-     UNION ALL
-
-     SELECT
-         *
-     FROM
-         pg_stat_all_indexes_internal
-     WHERE
-             relid < 16384) m, pg_stat_all_indexes_internal s
-WHERE m.indexrelid = s.indexrelid;
 
 CREATE VIEW pg_stat_sys_indexes AS
     SELECT * FROM pg_stat_all_indexes