comment trouver la taille de la base de données, schéma, tableau en redshift
Équipe
ma version redshift est:
PostgreSQL 8.0.2 on i686-pc-linux-gnu, compiled by GCC gcc (GCC) 3.4.2 20041017 (Red Hat 3.4.2-6.fc3), Redshift 1.0.735
comment savoir la taille de la base de données, tablespace, la taille du schéma et la taille de la table ?
mais ci-dessous ne sont pas de travail dans le redshift ( pour la version ci-dessus )
SELECT pg_database_size('db_name');
SELECT pg_size_pretty( pg_relation_size('table_name') );
y a-t-il une alternative pour le découvrir comme oracle ( à partir de DBA_SEGMENTS )
pour la taille de tble, j'ai la requête ci-dessous, mais pas sûr de la menaing exacte de MBYTES. Pour la troisième rangée, MBYTES = 372. ça veut dire 372 MB ?
select trim(pgdb.datname) as Database, trim(pgn.nspname) as Schema,
trim(a.name) as Table, b.mbytes, a.rows
from ( select db_id, id, name, sum(rows) as rows from stv_tbl_perm a group by db_id, id, name ) as a
join pg_class as pgc on pgc.oid = a.id
join pg_namespace as pgn on pgn.oid = pgc.relnamespace
join pg_database as pgdb on pgdb.oid = a.db_id
join (select tbl, count(*) as mbytes
from stv_blocklist group by tbl) b on a.id=b.tbl
order by a.db_id, a.name;
database | schema | table | mbytes | rows
---------------+--------------+------------------+--------+----------
postgres | public | company | 8 | 1
postgres | public | table_data1_1 | 7 | 1
postgres | proj_schema1 | table_data1 | 372 | 33867540
postgres | public | table_data1_2 | 40 | 2000001
(4 rows)
7 réponses
les réponses ci-dessus ne donnent pas toujours des réponses correctes pour l'espace de tableau utilisé. Le support AWS a donné cette requête à utiliser:
SELECT TRIM(pgdb.datname) AS Database,
TRIM(a.name) AS Table,
((b.mbytes/part.total::decimal)*100)::decimal(5,2) AS pct_of_total,
b.mbytes,
b.unsorted_mbytes
FROM stv_tbl_perm a
JOIN pg_database AS pgdb
ON pgdb.oid = a.db_id
JOIN ( SELECT tbl,
SUM( DECODE(unsorted, 1, 1, 0)) AS unsorted_mbytes,
COUNT(*) AS mbytes
FROM stv_blocklist
GROUP BY tbl ) AS b
ON a.id = b.tbl
JOIN ( SELECT SUM(capacity) AS total
FROM stv_partitions
WHERE part_begin = 0 ) AS part
ON 1 = 1
WHERE a.slice = 0
ORDER BY 4 desc, db_id, name;
Oui, mo dans votre exemple, 372Mb. Voici ce que j'ai été en utilisant:
select
cast(use2.usename as varchar(50)) as owner,
pgc.oid,
trim(pgdb.datname) as Database,
trim(pgn.nspname) as Schema,
trim(a.name) as Table,
b.mbytes,
a.rows
from
(select db_id, id, name, sum(rows) as rows
from stv_tbl_perm a
group by db_id, id, name
) as a
join pg_class as pgc on pgc.oid = a.id
left join pg_user use2 on (pgc.relowner = use2.usesysid)
join pg_namespace as pgn on pgn.oid = pgc.relnamespace
and pgn.nspowner > 1
join pg_database as pgdb on pgdb.oid = a.db_id
join
(select tbl, count(*) as mbytes
from stv_blocklist
group by tbl
) b on a.id = b.tbl
order by mbytes desc, a.db_id, a.name;
Je ne suis pas sûr de regrouper par base de données et scheme, Mais voici un court moyen d'obtenir l'utilisation par table,
SELECT tbl, name, size_mb FROM
(
SELECT tbl, count(*) AS size_mb
FROM stv_blocklist
GROUP BY tbl
)
LEFT JOIN
(select distinct id, name FROM stv_tbl_perm)
ON id = tbl
ORDER BY size_mb DESC
LIMIT 10;
des versions Modifiées de l'une des autres réponses. Ceci inclut le nom de la base de données, le nom du schéma, le nom de la table, le nombre total de lignes, la taille sur le disque et la taille non triée:
-- sort by row count
select trim(pgdb.datname) as Database, trim(pgns.nspname) as Schema, trim(a.name) as Table,
c.rows, ((b.mbytes/part.total::decimal)*100)::decimal(5,3) as pct_of_total, b.mbytes, b.unsorted_mbytes
from stv_tbl_perm a
join pg_class as pgtbl on pgtbl.oid = a.id
join pg_namespace as pgns on pgns.oid = pgtbl.relnamespace
join pg_database as pgdb on pgdb.oid = a.db_id
join (select tbl, sum(decode(unsorted, 1, 1, 0)) as unsorted_mbytes, count(*) as mbytes from stv_blocklist group by tbl) b on a.id=b.tbl
join (select id, sum(rows) as rows from stv_tbl_perm group by id) c on a.id=c.id
join (select sum(capacity) as total from stv_partitions where part_begin=0) as part on 1=1
where a.slice=0
order by 4 desc, db_id, name;
-- sort by space used
select trim(pgdb.datname) as Database, trim(pgns.nspname) as Schema, trim(a.name) as Table,
c.rows, ((b.mbytes/part.total::decimal)*100)::decimal(5,3) as pct_of_total, b.mbytes, b.unsorted_mbytes
from stv_tbl_perm a
join pg_class as pgtbl on pgtbl.oid = a.id
join pg_namespace as pgns on pgns.oid = pgtbl.relnamespace
join pg_database as pgdb on pgdb.oid = a.db_id
join (select tbl, sum(decode(unsorted, 1, 1, 0)) as unsorted_mbytes, count(*) as mbytes from stv_blocklist group by tbl) b on a.id=b.tbl
join (select id, sum(rows) as rows from stv_tbl_perm group by id) c on a.id=c.id
join (select sum(capacity) as total from stv_partitions where part_begin=0) as part on 1=1
where a.slice=0
order by 6 desc, db_id, name;
Vous pouvez consulter ce dépôt, je suis sûr que vous y trouverez des choses utiles.
https://github.com/awslabs/amazon-redshift-utils
pour répondre à votre question, vous pouvez utiliser cette vue: https://github.com/awslabs/amazon-redshift-utils/blob/master/src/AdminViews/v_space_used_per_tbl.sql
puis interrogez comme vous voulez.
e.g: select * from admin.v_space_used_per_tbl;
Cette requête est beaucoup plus facile:
-- Liste du Top 30 des plus grandes tables sur votre cluster
SELECT
"schema"
,"table" AS table_name
,ROUND((size/1024.0),2) AS "Size in Gigabytes"
,pct_used AS "Physical Disk Used by This Table"
FROM svv_table_info
ORDER BY pct_used DESC
LIMIT 30;
C'est ce que j'utilise(veuillez changer le nom de la base de données de 'mydb' à votre nom de base de données):
SELECT CAST(use2.usename AS VARCHAR(50)) AS OWNER
,TRIM(pgdb.datname) AS DATABASE
,TRIM(pgn.nspname) AS SCHEMA
,TRIM(a.NAME) AS TABLE
,(b.mbytes) / 1024 AS Gigabytes
,a.ROWS
FROM (
SELECT db_id
,id
,NAME
,SUM(ROWS) AS ROWS
FROM stv_tbl_perm a
GROUP BY db_id
,id
,NAME
) AS a
JOIN pg_class AS pgc ON pgc.oid = a.id
LEFT JOIN pg_user use2 ON (pgc.relowner = use2.usesysid)
JOIN pg_namespace AS pgn ON pgn.oid = pgc.relnamespace
AND pgn.nspowner > 1
JOIN pg_database AS pgdb ON pgdb.oid = a.db_id
JOIN (
SELECT tbl
,COUNT(*) AS mbytes
FROM stv_blocklist
GROUP BY tbl
) b ON a.id = b.tbl
WHERE pgdb.datname = 'mydb'
ORDER BY mbytes DESC
,a.db_id
,a.NAME;
src: https://aboutdatabases.wordpress.com/2015/01/24/amazon-redshift-how-to-get-the-sizes-of-all-tables/