Postgresql Useful SQL/Commands
- psqlrc
-- check active session
\set active_session 'select pid,usename,datname,application_name,client_addr,age(clock_timestamp(), query_start),query from pg_stat_activity where pid<>pg_backend_pid() and state=\'active\' order by query_start desc;' -- all_reslove_session
\set session 'select pid,usename,datname,application_name,client_addr,age(clock_timestamp(), query_start),query from pg_stat_activity where pid<>pg_backend_pid() and state=\'idle\' and upper(query) not like \'SET%\' and upper(query) not like \'SHOW%\' and query != \'COMMIT\' order by query_start desc;'
-- check wait events
\set wait_event 'select pid,application_name,client_addr,age(clock_timestamp(),query_start),state,wait_event_type,wait_event from pg_stat_activity where pid<>pg_backend_pid() and wait_event is not null order by wait_event_type;' -- table_size
\set table_size 'select table_name,pg_size_pretty(total_bytes) AS total, pg_size_pretty(index_bytes) AS idx , pg_size_pretty(toast_bytes) AS toast , pg_size_pretty(table_bytes) AS relsize from (select *, total_bytes-index_bytes-COALESCE(toast_bytes,0) AS table_bytes FROM ( SELECT c.oid,nspname AS table_schema, relname AS table_name , c.reltuples AS row_estimate , pg_total_relation_size(c.oid) AS total_bytes , pg_indexes_size(c.oid) AS index_bytes , pg_total_relation_size(reltoastrelid) AS toast_bytes FROM pg_class c LEFT JOIN pg_namespace n ON n.oid = c.relnamespace WHERE relkind = \'r\' and relname in (select tablename from pg_tables where schemaname=\'public\') ) a) a order by total_bytes desc;' --database size
\set database_size 'SELECT d.datname AS Name,pg_catalog.pg_get_userbyid(d.datdba) AS Owner,CASE WHEN pg_catalog.has_database_privilege(d.datname, \'CONNECT\') THEN pg_catalog.pg_size_pretty(pg_catalog.pg_database_size(d.datname)) ELSE \'No Access\' END AS SIZE FROM pg_catalog.pg_database d ORDER BY CASE WHEN pg_catalog.has_database_privilege(d.datname, \'CONNECT\') THEN pg_catalog.pg_database_size(d.datname) ELSE NULL END DESC LIMIT 20;' --redshift running sqls
\set redshift_run 'SELECT pid,starttime,duration,trim(user_name) AS user,trim(query) AS querytxt FROM stv_recents WHERE STATUS = \'Running\' order by starttime desc;' - Update records
update cloud_subscribers a set subscriber_location_id=b.subscriber_location_id from mtco_subscribers b where a.org_id='' and a.subscriber_id=b.subscriber_id;
get dead lines more than 100 :
SELECT schemaname||'.'||relname as table_name,pg_size_pretty(pg_relation_size(schemaname||'.'||relname)) as table_size,n_dead_tup,n_live_tup,round(n_dead_tup * 100 / (n_live_tup + n_dead_tup),2) AS dead_tup_ratio FROM
pg_stat_all_tables where n_dead_tup >= 100 ORDER BY pg_relation_size(schemaname||'.'||relname) DESC LIMIT 10;- 更新含有外键的记录
postgres=# with new_a as (update calixspid set orgid=5950 where orgid=291040) update calixorganization set id=5950 where id=291040;
UPDATE 1postgres=# \d calixspid
Table "public.calixspid"
Column | Type | Modifiers
--------+------------------------+------------------------------------------------
id | bigint | not null default nextval('spid_seq'::regclass)
orgid | bigint | not null
spid | character varying(255) |
Indexes:
"calixspid_pkey" PRIMARY KEY, btree (id)
Foreign-key constraints:
"calixspid_orgid_fkey" FOREIGN KEY (orgid) REFERENCES calixorganization(id) - Connections
select count(*) from pg_stat_activity;
select client_addr,state,count(*) from pg_stat_activity group by client_addr,state order by count(*) desc;
select max_conn,used,res_for_super,max_conn-used-res_for_super res_for_normal
from (select count(*) used from pg_stat_activity) t1,
(select setting::int res_for_super from pg_settings where name=$$superuser_reserved_connections$$) t2,
(select setting::int max_conn from pg_settings where name=$$max_connections$$) t3;- Show Running Sql
-- show running queries (pre 9.2)
SELECT procpid, age(clock_timestamp(), query_start), usename, current_query
FROM pg_stat_activity
WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%'
ORDER BY query_start desc;
-- show running queries (9.2)
SELECT pid, age(clock_timestamp(), query_start), usename, query
FROM pg_stat_activity
WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%'
ORDER BY query_start desc; -- show running sqls more than 2 mins (9.2+)
SELECT now() - query_start as "runtime", usename, datname, state, query
FROM pg_stat_activity
WHERE now() - query_start > '2 minutes'::interval
ORDER BY runtime DESC; --show all queries
select substr(query,1,100) query,backend_type,application_name,query_start,wait_event_type,wait_event,state from pg_stat_activity;- Vacuum
--get vacuum status and results
select relname,last_vacuum, last_autovacuum, last_analyze, last_autoanalyze from pg_stat_user_tables; --query by sigle table of vacuum status
select relname, n_dead_tup, last_vacuum, last_autovacuum from pg_catalog.pg_stat_all_tables where n_dead_tup > 0 and relname ='sxacc-devices' order by n_dead_tup desc; -- vacuum command
VACUUM (VERBOSE, ANALYZE);
- Database and Tables releated
-- table index usage rates (should not be less than 0.99)
SELECT relname,
CASE WHEN (seq_scan + idx_scan) != 0
THEN 100.0 * idx_scan / (seq_scan + idx_scan)
ELSE 0
END AS percent_of_times_index_used,
n_live_tup AS rows_in_table
FROM pg_stat_user_tables
ORDER BY n_live_tup DESC; -- all database users
select * from pg_stat_activity where current_query not like '<%'; -- all databases and their sizes
select * from pg_user; -- all tables and their size, with/without indexes
select datname, pg_size_pretty(pg_database_size(datname)) from pg_database order by pg_database_size(datname) desc; -- cache hit rates (should not be less than 0.99)
SELECT sum(heap_blks_read) as heap_read, sum(heap_blks_hit) as heap_hit, (sum(heap_blks_hit) - sum(heap_blks_read)) / sum(heap_blks_hit) as ratio FROM pg_statio_user_tables; -- table index usage rates (should not be less than 0.99)
SELECT relname, 100 * idx_scan / (seq_scan + idx_scan) percent_of_times_index_used, n_live_tup rows_in_table FROM pg_stat_user_tables ORDER BY n_live_tup DESC; -- how many indexes are in cache
SELECT sum(idx_blks_read) as idx_read, sum(idx_blks_hit) as idx_hit, (sum(idx_blks_hit) - sum(idx_blks_read)) / sum(idx_blks_hit) as ratio FROM pg_statio_user_indexes; -- check the size(as in disk space) of all databases;
SELECT d.datname AS Name, pg_catalog.pg_get_userbyid(d.datdba) AS Owner,
CASE WHEN pg_catalog.has_database_privilege(d.datname, 'CONNECT')
THEN pg_catalog.pg_size_pretty(pg_catalog.pg_database_size(d.datname))
ELSE 'No Access'
END AS SIZE
FROM pg_catalog.pg_database d
ORDER BY
CASE WHEN pg_catalog.has_database_privilege(d.datname, 'CONNECT')
THEN pg_catalog.pg_database_size(d.datname)
ELSE NULL
END;
--check the size(as in space) of each table
SELECT nspname || '.' || relname AS "relation",
pg_size_pretty(pg_total_relation_size(C.oid)) AS "total_size"
FROM pg_class C
LEFT JOIN pg_namespace N ON (N.oid = C.relnamespace)
WHERE nspname NOT IN ('pg_catalog', 'information_schema')
AND C.relkind <> 'i'
AND nspname !~ '^pg_toast'
ORDER BY pg_total_relation_size(C.oid) DESC;-- all tables and their size, with/without indexes
select datname, pg_size_pretty(pg_database_size(datname))
from pg_database
order by pg_database_size(datname) desc;
-- show unused indexes:
SELECT relname AS table_name, indexrelname AS index_name, idx_scan, idx_tup_read, idx_tup_fetch, pg_size_pretty(pg_relation_size(indexrelname::regclass))
FROM pg_stat_all_indexes
WHERE schemaname = 'public'
AND idx_scan = 0
AND idx_tup_read = 0
AND idx_tup_fetch = 0
ORDER BY pg_relation_size(indexrelname::regclass) DESC;- locks
-- all locks
SELECT t.relname, l.locktype, page, virtualtransaction, pid, mode, granted
FROM pg_locks l, pg_stat_all_tables t
WHERE l.relation = t.relid ORDER BY relation asc; -- Сombination of blocked and blocking activity
-- The following query may be helpful to see what processes are blocking SQL statements (these only find row-level locks, not object-level locks).
SELECT blocked_locks.pid AS blocked_pid,
blocked_activity.usename AS blocked_user,
blocking_locks.pid AS blocking_pid,
blocking_activity.usename AS blocking_user,
blocked_activity.query AS blocked_statement,
blocking_activity.query AS current_statement_in_blocking_process
FROM pg_catalog.pg_locks blocked_locks
JOIN pg_catalog.pg_stat_activity blocked_activity ON blocked_activity.pid = blocked_locks.pid
JOIN pg_catalog.pg_locks blocking_locks
ON blocking_locks.locktype = blocked_locks.locktype
AND blocking_locks.DATABASE IS NOT DISTINCT FROM blocked_locks.DATABASE
AND blocking_locks.relation IS NOT DISTINCT FROM blocked_locks.relation
AND blocking_locks.page IS NOT DISTINCT FROM blocked_locks.page
AND blocking_locks.tuple IS NOT DISTINCT FROM blocked_locks.tuple
AND blocking_locks.virtualxid IS NOT DISTINCT FROM blocked_locks.virtualxid
AND blocking_locks.transactionid IS NOT DISTINCT FROM blocked_locks.transactionid
AND blocking_locks.classid IS NOT DISTINCT FROM blocked_locks.classid
AND blocking_locks.objid IS NOT DISTINCT FROM blocked_locks.objid
AND blocking_locks.objsubid IS NOT DISTINCT FROM blocked_locks.objsubid
AND blocking_locks.pid != blocked_locks.pid JOIN pg_catalog.pg_stat_activity blocking_activity ON blocking_activity.pid = blocking_locks.pid
WHERE NOT blocked_locks.GRANTED; -- Here's an alternate view of that same data that includes application_name's -- Setting application_name variable in the begging of each transaction allows you to which logical process blocks another one. It can be information which source code line starts transaction or any other information that helps you to match application_name to your code.
SET application_name='%your_logical_name%'; SELECT blocked_locks.pid AS blocked_pid,
blocked_activity.usename AS blocked_user,
blocking_locks.pid AS blocking_pid,
blocking_activity.usename AS blocking_user,
blocked_activity.query AS blocked_statement,
blocking_activity.query AS current_statement_in_blocking_process,
blocked_activity.application_name AS blocked_application,
blocking_activity.application_name AS blocking_application
FROM pg_catalog.pg_locks blocked_locks
JOIN pg_catalog.pg_stat_activity blocked_activity ON blocked_activity.pid = blocked_locks.pid
JOIN pg_catalog.pg_locks blocking_locks
ON blocking_locks.locktype = blocked_locks.locktype
AND blocking_locks.DATABASE IS NOT DISTINCT FROM blocked_locks.DATABASE
AND blocking_locks.relation IS NOT DISTINCT FROM blocked_locks.relation
AND blocking_locks.page IS NOT DISTINCT FROM blocked_locks.page
AND blocking_locks.tuple IS NOT DISTINCT FROM blocked_locks.tuple
AND blocking_locks.virtualxid IS NOT DISTINCT FROM blocked_locks.virtualxid
AND blocking_locks.transactionid IS NOT DISTINCT FROM blocked_locks.transactionid
AND blocking_locks.classid IS NOT DISTINCT FROM blocked_locks.classid
AND blocking_locks.objid IS NOT DISTINCT FROM blocked_locks.objid
AND blocking_locks.objsubid IS NOT DISTINCT FROM blocked_locks.objsubid
AND blocking_locks.pid != blocked_locks.pid JOIN pg_catalog.pg_stat_activity blocking_activity ON blocking_activity.pid = blocking_locks.pid
WHERE NOT blocked_locks.GRANTED; -- Here's an alternate view of that same data that includes an idea how old the state is
SELECT a.datname,
l.relation::regclass,
l.transactionid,
l.mode,
l.GRANTED,
a.usename,
a.query,
a.query_start,
age(now(), a.query_start) AS "age",
a.pid
FROM pg_stat_activity a
JOIN pg_locks l ON l.pid = a.pid
ORDER BY a.query_start; -- Flat view of Blocking
-- For PostgreSQL Version < 9.2
SELECT
waiting.locktype AS waiting_locktype,
waiting.relation::regclass AS waiting_table,
waiting_stm.current_query AS waiting_query,
waiting.mode AS waiting_mode,
waiting.pid AS waiting_pid,
other.locktype AS other_locktype,
other.relation::regclass AS other_table,
other_stm.current_query AS other_query,
other.mode AS other_mode,
other.pid AS other_pid,
other.GRANTED AS other_granted
FROM
pg_catalog.pg_locks AS waiting
JOIN
pg_catalog.pg_stat_activity AS waiting_stm
ON (
waiting_stm.procpid = waiting.pid
)
JOIN
pg_catalog.pg_locks AS other
ON (
(
waiting."database" = other."database"
AND waiting.relation = other.relation
)
OR waiting.transactionid = other.transactionid
)
JOIN
pg_catalog.pg_stat_activity AS other_stm
ON (
other_stm.procpid = other.pid
)
WHERE
NOT waiting.GRANTED
AND
waiting.pid <> other.pid -- For PostgreSQL Version >= 9.2
SELECT
waiting.locktype AS waiting_locktype,
waiting.relation::regclass AS waiting_table,
waiting_stm.query AS waiting_query,
waiting.mode AS waiting_mode,
waiting.pid AS waiting_pid,
other.locktype AS other_locktype,
other.relation::regclass AS other_table,
other_stm.query AS other_query,
other.mode AS other_mode,
other.pid AS other_pid,
other.GRANTED AS other_granted
FROM
pg_catalog.pg_locks AS waiting
JOIN
pg_catalog.pg_stat_activity AS waiting_stm
ON (
waiting_stm.pid = waiting.pid
)
JOIN
pg_catalog.pg_locks AS other
ON (
(
waiting."database" = other."database"
AND waiting.relation = other.relation
)
OR waiting.transactionid = other.transactionid
)
JOIN
pg_catalog.pg_stat_activity AS other_stm
ON (
other_stm.pid = other.pid
)
WHERE
NOT waiting.GRANTED
AND
waiting.pid <> other.pid -- Recursive View of Blocking
WITH RECURSIVE
c(requested, CURRENT) AS
( VALUES
('AccessShareLock'::text, 'AccessExclusiveLock'::text),
('RowShareLock'::text, 'ExclusiveLock'::text),
('RowShareLock'::text, 'AccessExclusiveLock'::text),
('RowExclusiveLock'::text, 'ShareLock'::text),
('RowExclusiveLock'::text, 'ShareRowExclusiveLock'::text),
('RowExclusiveLock'::text, 'ExclusiveLock'::text),
('RowExclusiveLock'::text, 'AccessExclusiveLock'::text),
('ShareUpdateExclusiveLock'::text, 'ShareUpdateExclusiveLock'::text),
('ShareUpdateExclusiveLock'::text, 'ShareLock'::text),
('ShareUpdateExclusiveLock'::text, 'ShareRowExclusiveLock'::text),
('ShareUpdateExclusiveLock'::text, 'ExclusiveLock'::text),
('ShareUpdateExclusiveLock'::text, 'AccessExclusiveLock'::text),
('ShareLock'::text, 'RowExclusiveLock'::text),
('ShareLock'::text, 'ShareUpdateExclusiveLock'::text),
('ShareLock'::text, 'ShareRowExclusiveLock'::text),
('ShareLock'::text, 'ExclusiveLock'::text),
('ShareLock'::text, 'AccessExclusiveLock'::text),
('ShareRowExclusiveLock'::text, 'RowExclusiveLock'::text),
('ShareRowExclusiveLock'::text, 'ShareUpdateExclusiveLock'::text),
('ShareRowExclusiveLock'::text, 'ShareLock'::text),
('ShareRowExclusiveLock'::text, 'ShareRowExclusiveLock'::text),
('ShareRowExclusiveLock'::text, 'ExclusiveLock'::text),
('ShareRowExclusiveLock'::text, 'AccessExclusiveLock'::text),
('ExclusiveLock'::text, 'RowShareLock'::text),
('ExclusiveLock'::text, 'RowExclusiveLock'::text),
('ExclusiveLock'::text, 'ShareUpdateExclusiveLock'::text),
('ExclusiveLock'::text, 'ShareLock'::text),
('ExclusiveLock'::text, 'ShareRowExclusiveLock'::text),
('ExclusiveLock'::text, 'ExclusiveLock'::text),
('ExclusiveLock'::text, 'AccessExclusiveLock'::text),
('AccessExclusiveLock'::text, 'AccessShareLock'::text),
('AccessExclusiveLock'::text, 'RowShareLock'::text),
('AccessExclusiveLock'::text, 'RowExclusiveLock'::text),
('AccessExclusiveLock'::text, 'ShareUpdateExclusiveLock'::text),
('AccessExclusiveLock'::text, 'ShareLock'::text),
('AccessExclusiveLock'::text, 'ShareRowExclusiveLock'::text),
('AccessExclusiveLock'::text, 'ExclusiveLock'::text),
('AccessExclusiveLock'::text, 'AccessExclusiveLock'::text)
),
l AS
(
SELECT
(locktype,DATABASE,relation::regclass::text,page,tuple,virtualxid,transactionid,classid,objid,objsubid) AS target,
virtualtransaction,
pid,
mode,
GRANTED
FROM pg_catalog.pg_locks
),
t AS
(
SELECT
blocker.target AS blocker_target,
blocker.pid AS blocker_pid,
blocker.mode AS blocker_mode,
blocked.target AS target,
blocked.pid AS pid,
blocked.mode AS mode
FROM l blocker
JOIN l blocked
ON ( NOT blocked.GRANTED
AND blocker.GRANTED
AND blocked.pid != blocker.pid
AND blocked.target IS NOT DISTINCT FROM blocker.target)
JOIN c ON (c.requested = blocked.mode AND c.CURRENT = blocker.mode)
),
r AS
(
SELECT
blocker_target,
blocker_pid,
blocker_mode,
'1'::INT AS depth,
target,
pid,
mode,
blocker_pid::text || ',' || pid::text AS seq
FROM t
UNION ALL
SELECT
blocker.blocker_target,
blocker.blocker_pid,
blocker.blocker_mode,
blocker.depth + 1,
blocked.target,
blocked.pid,
blocked.mode,
blocker.seq || ',' || blocked.pid::text
FROM r blocker
JOIN t blocked
ON (blocked.blocker_pid = blocker.pid)
WHERE blocker.depth < 1000
)
SELECT * FROM r
ORDER BY seq; -- the following view also adds useful information about the sessions in the blocking tree.
CREATE OR REPLACE VIEW blocking_tree AS
WITH RECURSIVE
LOCK AS (
SELECT pid,
virtualtransaction,
GRANTED,
mode,
(locktype,
CASE locktype
WHEN 'relation' THEN concat_ws(';', 'db:'||datname, 'rel:'||relation::regclass::text)
WHEN 'extend' THEN concat_ws(';', 'db:'||datname, 'rel:'||relation::regclass::text)
WHEN 'page' THEN concat_ws(';', 'db:'||datname, 'rel:'||relation::regclass::text, 'page#'||page::text)
WHEN 'tuple' THEN concat_ws(';', 'db:'||datname, 'rel:'||relation::regclass::text, 'page#'||page::text, 'tuple#'||tuple::text)
WHEN 'transactionid' THEN transactionid::text
WHEN 'virtualxid' THEN virtualxid::text
WHEN 'object' THEN concat_ws(';', 'class:'||classid::regclass::text, 'objid:'||objid, 'col#'||objsubid)
ELSE concat('db:'||datname) -- userlock and advisory
END::text) AS target
FROM pg_catalog.pg_locks
LEFT JOIN pg_catalog.pg_database ON (pg_database.oid = pg_locks.DATABASE)
)
, waiting_lock AS (
SELECT
blocker.pid AS blocker_pid,
blocked.pid AS pid,
concat(blocked.mode,blocked.target) AS lock_target
FROM LOCK blocker
JOIN LOCK blocked
ON ( NOT blocked.GRANTED
AND blocker.GRANTED
AND blocked.pid != blocker.pid
AND blocked.target IS NOT DISTINCT FROM blocker.target)
JOIN lock_composite c ON (c.requested = blocked.mode AND c.CURRENT = blocker.mode)
)
, acquired_lock AS (
WITH waiting AS (
SELECT lock_target, COUNT(lock_target) AS wait_count FROM waiting_lock GROUP BY lock_target
)
SELECT
pid,
array_agg(concat(mode,target,' + '||wait_count) ORDER BY wait_count DESC NULLS LAST) AS locks_acquired
FROM LOCK
LEFT JOIN waiting ON waiting.lock_target = concat(mode,target)
WHERE GRANTED
GROUP BY pid
)
, blocking_lock AS (
SELECT
ARRAY[date_part('epoch', query_start)::INT, pid] AS seq,
0::INT AS depth,
-1::INT AS blocker_pid,
pid,
concat('Connect: ',usename,' ',datname,' ',COALESCE(host(client_addr)||':'||client_port, 'local')
, E'\nSQL: ',REPLACE(substr(COALESCE(query,'N/A'), 1, 60), E'\n', ' ')
, E'\nAcquired:\n '
, array_to_string(locks_acquired[1:5] ||
CASE WHEN array_upper(locks_acquired,1) > 5
THEN '... '||(array_upper(locks_acquired,1) - 5)::text||' more ...'
END,
E'\n ')
) AS lock_info,
concat(to_char(query_start, CASE WHEN age(query_start) > '24h' THEN 'Day DD Mon' ELSE 'HH24:MI:SS' END),E' started\n'
,CASE WHEN waiting THEN 'waiting' ELSE state END,E'\n'
,date_trunc('second',age(now(),query_start)),' ago'
) AS lock_state
FROM acquired_lock blocker
LEFT JOIN pg_stat_activity act USING (pid)
WHERE EXISTS -- The root of the tree should blocks one or more sessions.
(SELECT 'x' FROM waiting_lock blocked WHERE blocked.blocker_pid = blocker.pid)
AND NOT EXISTS -- The root of the tree should not be a blocked session.
(SELECT 'x' FROM waiting_lock blocked WHERE blocked.pid = blocker.pid)
UNION ALL
SELECT
blocker.seq || blocked.pid,
blocker.depth + 1,
blocker.pid,
blocked.pid,
concat('Connect: ',usename,' ',datname,' ',COALESCE(host(client_addr)||':'||client_port, 'local')
, E'\nSQL: ',REPLACE(substr(COALESCE(query,'N/A'), 1, 60), E'\n', ' ')
, E'\nWaiting: ',blocked.lock_target
, CASE WHEN locks_acquired IS NOT NULL
THEN E'\nAcquired:\n ' ||
array_to_string(locks_acquired[1:5] ||
CASE WHEN array_upper(locks_acquired,1) > 5
THEN '... '||(array_upper(locks_acquired,1) - 5)::text||' more ...'
END,
E'\n ')
END
) AS lock_info,
concat(to_char(query_start, CASE WHEN age(query_start) > '24h' THEN 'Day DD Mon' ELSE 'HH24:MI:SS' END),E' started\n'
,CASE WHEN waiting THEN 'waiting' ELSE state END,E'\n'
,date_trunc('second',age(now(),query_start)),' ago'
) AS lock_state
FROM blocking_lock blocker
JOIN waiting_lock blocked
ON (blocked.blocker_pid = blocker.pid)
LEFT JOIN pg_stat_activity act ON (act.pid = blocked.pid)
LEFT JOIN acquired_lock acq ON (acq.pid = blocked.pid)
WHERE blocker.depth < 5
)
SELECT concat(lpad('=> ', 4*depth, ' '),pid::text) AS "PID"
, lock_info AS "Lock Info"
, lock_state AS "State"
FROM blocking_lock
ORDER BY seq;Other Operations
-- Dump database on remote host to file
$ pg_dump -U username -h hostname databasename > dump.sql -- Import dump into existing database
$ psql -d newdb -f dump.sql -- kill running query
SELECT pg_cancel_backend(procpid); -- kill idle query
SELECT pg_terminate_backend(procpid);- postgres upgrading
# Taken from http://robots.thoughtbot.com/post/33706558963/migrating-data-from-an-upgraded-postgres
#
# Note: these steps assume installation with Homebrew. # Initialize a new database, adding a .new suffix to the directory that Homebrew recommends. initdb /usr/local/var/postgres.new -E utf8 # Run the upgrade script, providing the correct paths for the various flags. pg_upgrade \
-b /usr/local/Cellar/postgresql/9.1.4/bin \
-B /usr/local/Cellar/postgresql/9.2.1/bin \
-d /usr/local/var/postgres \
-D /usr/local/var/postgres.new # Put the data in the correct place. rm -rf /usr/local/var/postgres
mv /usr/local/var/postgres.new /usr/local/var/postgres # If you’ve set up launchd to run Postgres automatically,
# everything should be up and running! Otherwise, check out the
# documentation with brew info postgres to read how to have OS X
# manage postgres for you. ####### # Alternatively, if you’ve just upgraded Postgres with Homebrew and
# Postgres won’t start, as long as you don’t care about any data stored locally: brew remove --force postgresql
rm -rf /usr/local/var/postgres/
brew install postgresql- postgresql configuration optimization
Memory
Only four values really matter:
shared-buffers: below 2GB: set it to 20% of full memory; below 32GB: 25% of your full memory.
work_mem: Start low at 32/64MB. Look for temporary file lines in logs. Then set it to 2-3x the largest temp file that you see. This setting can give a huge speed boost (if set properly).
maintenance_work_mem: Set it to 10% of system memory.
effective_cache_size: Only a hint to postgres. Just set it to the amount of filesystem cache available.
Reference:
- https://gist.github.com/rgreenjr/3637525
- https://wiki.postgresql.org/wiki/Lock_dependency_information
- https://wiki.postgresql.org/wiki/Lock_Monitoring
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