web-dev-qa-db-fra.com

comment trouver la taille de la base de données, du schéma, de la table dans 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 connaître la taille de la base de données, l'espace disque logique, la taille du schéma et la taille de la table?

mais ci-dessous ne fonctionne pas en redshift (pour la version ci-dessus)

SELECT pg_database_size('db_name');
SELECT pg_size_pretty( pg_relation_size('table_name') );

Existe-t-il une alternative à découvrir comme Oracle (à partir de DBA_SEGMENTS)

pour la taille de table, j'ai ci-dessous la requête, mais je ne suis pas sûr de la menaing exacte de MBYTES. POUR la 3ème ligne, MBYTES = 372. cela signifie 372 Mo?

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)
amazon-web-servicesamazon-redshift
41
user3258784

Les réponses ci-dessus ne donnent pas toujours des réponses correctes pour l'espace table 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;
60
imcdnzl

Oui, mbytes dans votre exemple est 372Mb. Voici ce que j'utilise:

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;
19
mike_pdb

Je ne suis pas sûr du regroupement par base de données et schéma, mais voici un moyen rapide d'obtenir une 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;
11
gatoatigrado

Versions modifiées de l'une des autres réponses. Cela 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;
7
Nate Sammons

vous pouvez consulter ce référentiel, je suis sûr que vous y trouverez des informations 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 le souhaitez. par exemple: select * from admin.v_space_used_per_tbl;

7
kerbelp

Cette requête est beaucoup plus simple:

- Listez les 30 plus grandes tables de 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;
2
Qiushuo Yu