PostgreSQL如何查询每个表的大小

PostgreSQL如何查询每个表的大小

1、查询数据库中单个表的大小（不包含索引）

select pg_size_pretty(pg_relation_size('表名'));

2、查询所有表的大小并排序（包含索引）

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SELECT table_schema || '.' || table_name AS table_full_name, pg_size_pretty(pg_total_relation_size('"' 
    || table_schema || '"."' || table_name || '"')) AS size
FROM information_schema.tables
ORDER BY
pg_total_relation_size('"' || table_schema || '"."' || table_name || '"') DESC limit 20

3、查询表大小按大小排序并分离data与index

SELECT
table_name,
pg_size_pretty(table_size) AS table_size,
pg_size_pretty(indexes_size) AS indexes_size,
pg_size_pretty(total_size) AS total_size
FROM (
SELECT
table_name,
pg_table_size(table_name) AS table_size,
pg_indexes_size(table_name) AS indexes_size,
pg_total_relation_size(table_name) AS total_size
FROM (
SELECT ('"' || table_schema || '"."' || table_name || '"') AS table_name
FROM information_schema.tables
) AS all_tables
ORDER BY total_size DESC
) AS pretty_sizes

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