select relname,n_live_tup, n_tup_upd, n_tup_del, n_dead_tup, last_vacuum, last_autovacuum, last_analyze, last_autoanalyze from pg_stat_all_tables order by n_dead_tup desc limit 50;
@@ -651,7 +661,7 @@ SELECT e.extname AS "Extension Name", e.extversion AS "Version", n.nspname AS "S
FROM pg_catalog.pg_extension e LEFT JOIN pg_catalog.pg_namespace n ON n.oid = e.extnamespace LEFT JOIN pg_catalog.pg_description c ON c.objoid = e.oid AND c.classoid = 'pg_catalog.pg_extension'::pg_catalog.regclass
ORDER BY 1;
\qecho
-\qecho Available Extension versions that are available to upgrade the instaelled Extension:
+\qecho Available Extension versions that are available to upgrade the installed Extension:
select b.name as extension_name , b.version as version ,b.installed as installed
from
(SELECT extname ,extversion FROM pg_extension) a ,
@@ -660,7 +670,7 @@ where a.extname = b.name
and b.version > a.extversion
order by b.name , b.version;
\qecho
-\qecho Latest Extension version that is available to upgrade the instaelled Extension:
+\qecho Latest Extension version that is available to upgrade the installed Extension:
select name as extension_name , max(version) as latest_version
from
(select b.name , b.version ,b.installed
@@ -919,11 +929,103 @@ select * FROM pg_user;
\qecho
\qecho Schema Info
\qecho
+\qecho List of schemas:
+\qecho
\qecho
--- List of schema
\dn+
\qecho
-
+\qecho
+\qecho Total objects Count in the database:
+\qecho
+\qecho
+select count (*) from pg_catalog.pg_class;
+\qecho
+\qecho
+\qecho objects count per schema :
+\qecho
+\qecho
+select
+n.nspname as schema_name, count (*)
+from pg_catalog.pg_class c
+lEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
+GROUP BY n.nspname
+order by 2 desc ;
+\qecho
+\qecho
+\qecho object type count per schema:
+\qecho
+\qecho
+SELECT
+n.nspname as schema_name
+,CASE c.relkind
+ WHEN 'r' THEN 'table'
+ WHEN 'v' THEN 'view'
+ WHEN 'i' THEN 'index'
+ WHEN 'S' THEN 'sequence'
+ WHEN 't' THEN 'TOAST table'
+ WHEN 'm' THEN 'materialized view'
+ WHEN 'c' THEN 'composite type'
+ WHEN 'f' THEN 'foreign table'
+ WHEN 'p' THEN 'partitioned table'
+ WHEN 'I' THEN 'partitioned index'
+END as object_type
+,count(1) as object_count
+FROM pg_catalog.pg_class c
+LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
+WHERE c.relkind IN ('r','v','i','S','s')
+GROUP BY n.nspname,
+CASE c.relkind
+ WHEN 'r' THEN 'table'
+ WHEN 'v' THEN 'view'
+ WHEN 'i' THEN 'index'
+ WHEN 'S' THEN 'sequence'
+ WHEN 't' THEN 'TOAST table'
+ WHEN 'm' THEN 'materialized view'
+ WHEN 'c' THEN 'composite type'
+ WHEN 'f' THEN 'foreign table'
+ WHEN 'p' THEN 'partitioned table'
+ WHEN 'I' THEN 'partitioned index'
+END
+ORDER BY n.nspname,
+CASE c.relkind
+ WHEN 'r' THEN 'table'
+ WHEN 'v' THEN 'view'
+ WHEN 'i' THEN 'index'
+ WHEN 'S' THEN 'sequence'
+ WHEN 't' THEN 'TOAST table'
+ WHEN 'm' THEN 'materialized view'
+ WHEN 'c' THEN 'composite type'
+ WHEN 'f' THEN 'foreign table'
+ WHEN 'p' THEN 'partitioned table'
+ WHEN 'I' THEN 'partitioned index'
+END;
+\qecho
+\qecho
+\qecho list of objects:
+\qecho
+\qecho
+select nsp.nspname as schema,
+ rol.rolname as owner,
+ cls.relname as object_name,
+ case cls.relkind
+ WHEN 'r' THEN 'table'
+ WHEN 'v' THEN 'view'
+ WHEN 'i' THEN 'index'
+ WHEN 'S' THEN 'sequence'
+ WHEN 't' THEN 'TOAST table'
+ WHEN 'm' THEN 'materialized view'
+ WHEN 'c' THEN 'composite type'
+ WHEN 'f' THEN 'foreign table'
+ WHEN 'p' THEN 'partitioned table'
+ WHEN 'I' THEN 'partitioned index'
+ else cls.relkind::text
+ end as object_type
+from pg_class cls
+ join pg_roles rol on rol.oid = cls.relowner
+ join pg_namespace nsp on nsp.oid = cls.relnamespace
+order by 1,2,4;
+\qecho
+\qecho
\qecho [Top]
@@ -1431,12 +1533,26 @@ ORDER BY 8 desc;
\qecho
\qecho Toast Tables Mapping
\qecho
+\qecho Note:
+\qecho When a column is written to the toast table, an OID is used to identify the chunk to be toasted. When a toast table grows very large, and contains chunk_ids that are nearing the value of 2^32, it can lead to performance degredation when writing to toast. This is because PostgreSQL must check if an OID is available for assignment by scanning the table
+\qecho A large Toast table can be a good indication that your toast can face OID wraparound
+\qecho over time the insert statement will be slower as the Database will be searching for an unused OID and it will have to read from the disk , you will see the insert statements is waiting on IPC:BufferiO or IO:DataFileRead
+\qecho you can use below SQL to check the toast table
+\qecho select COUNT(DISTINCT chunk_id),2^31 - COUNT(DISTINCT chunk_id) as remaining_OID ,ROUND(100*((2^31 - COUNT(DISTINCT chunk_id)))/2^31::float) AS remaining_OID_PCT ,ROUND(100*(COUNT(DISTINCT chunk_id)/2^31::float)) as percent_towards_Toast_oid_wraparound from pg_toast.pg_toast_{number};
+\qecho
+\qecho when the toast hits the OID wraparound, you will see the following wait event LWLock:OidGen and the insert statements will fail and you will see below error in the log file
+\qecho
+\qecho :LOG: still searching for an unused OID in relation "pg_toast_{number}"
+\qecho :DETAIL: OID candidates have been checked 1000000 times, but no unused OID has been found yet.
+\qecho
+\qecho Toast Tables Mapping and sizes:
+\qecho
\qecho
-select t.relname table_name, r.relname toast_name, pg_size_pretty(pg_relation_size(t.reltoastrelid)) as toast_size
+select t.relname table_name, r.relname toast_name,r.oid as toast_oid, pg_relation_size(t.reltoastrelid) as toast_size_bytes ,pg_size_pretty(pg_relation_size(t.reltoastrelid)) as toast_size
FROM
pg_class r
INNER JOIN pg_class t ON r.oid = t.reltoastrelid
-order by r.relname ;
+order by toast_size_bytes desc ;
\qecho
\qecho [Top]
@@ -1515,26 +1631,62 @@ WHERE name in ('wal_level','max_wal_senders','max_replication_slots',
\qecho
\qecho Sessions/Connections Info
\qecho
-\qecho
\qecho Connections utilization:
+\qecho
+\qecho
with
settings as (SELECT setting::float AS "max_connections" FROM pg_settings WHERE name = 'max_connections'),
connections as (select sum (numbackends)::float total_connections from pg_stat_database)
select settings.max_connections AS "Max_connections" ,total_connections as "Total_connections",ROUND((100*(connections.Total_connections/settings.max_connections))::numeric,2) as "Connections utilization %" from settings, connections;
+\qecho
+\qecho
+\qecho Reserved connections settings:
+\qecho
+\qecho
+select name as parameter_name , setting , short_desc from pg_settings WHERE name in ('superuser_reserved_connections', 'rds.rds_superuser_reserved_connections');
+\qecho
+\qecho
\qecho DB/Connections count :
+\qecho
+\qecho
SELECT datname as "Database_Name",count(*) as "Connections_count" FROM pg_stat_activity where datname is not null group by datname order by 2 desc;
+\qecho
+\qecho
\qecho DB/username/Connections count :
+\qecho
+\qecho
SELECT datname as "Database_Name",usename as "User_Name" ,count(*) as "Connections_count" FROM pg_stat_activity where datname is not null group by datname,usename order by 1,3 desc;
+\qecho
+\qecho
\qecho username/Connections count :
+\qecho
+\qecho
SELECT usename as "User_Name",count(*) as "connections_count" FROM pg_stat_activity where datname is not null group by usename order by 2 desc;
+\qecho
+\qecho
\qecho username/status/Connections count :
+\qecho
+\qecho
SELECT usename as "User_Name",state as status,count(*) as "Connections_count" FROM pg_stat_activity where datname is not null group by usename,state order by 1,2 desc;
+\qecho
+\qecho
+\qecho DB/username/status/Connections count :
+\qecho
+\qecho
+select datname as "Database_Name" ,usename as "User_Name",state as status,count(*) as "Connections_count" FROM pg_stat_activity where datname is not null group by datname ,usename,state order by 4 desc;
+\qecho
+\qecho
\qecho status/Connections count :
+\qecho
+\qecho
SELECT state as status ,count(*) as "Connections_count" FROM pg_stat_activity where datname is not null GROUP BY status order by 2 desc;
+\qecho
+\qecho
\qecho username/status/SQL/count :
+\qecho
+\qecho
SELECT usename as "User_Name" , state as status , query, count(*) FROM pg_stat_activity where datname is not null group by usename,state,query ;
\qecho
-
\qecho
\qecho Active sessions:
\qecho
@@ -2212,13 +2364,13 @@ order by total_time desc;
\qecho
\qecho DB Load
\qecho
-\qecho How many session waiting on CPU and None CPU wait event:
+\qecho How many session waiting on CPU and Non CPU wait event:
\qecho
select coalesce(count(*),'0') as count_of_sessions_waiting_on_CPU
FROM pg_stat_activity
where wait_event is null and state = 'active' group by wait_event ;
\qecho
-select coalesce(sum(count),'0') as count_of_sessions_waiting_on_None_CPU
+select coalesce(sum(count),'0') as count_of_sessions_waiting_on_Non_CPU
from (SELECT count(*) as count
FROM pg_stat_activity
where wait_event is not null and state = 'active'