테이블의 물리적 크기를 측정하는 방법
[링크 : https://www.a2hosting.com/.../postgresql/determining-the-size-of-postgresql-databases-and-tables]
table 별 table / index / toast(이게 먼지 모르겠음) 용량 byte와 MB 단위로 나오는 쿼리문
SELECT *, pg_size_pretty(total_bytes) AS total , pg_size_pretty(index_bytes) AS INDEX , pg_size_pretty(toast_bytes) AS toast , pg_size_pretty(table_bytes) AS TABLE 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' ) a ) a; |
[링크 : https://wiki.postgresql.org/wiki/Disk_Usage]
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LZ 압축 기술로 압축하여 저장하는 공간인가?
TOAST(대형 속성 저장 기술:The Oversized-Attribute Storage Technique)
[링크 : http:// http://www.postgresql.org/docs/9.4/static/storage-toast.html]
[링크 : https://data-rider.blogspot.com/2015/07/postgresql-toast.html]