PostgreSQL数据库中查看表和索引大小的方法

一、查看所有public schema里面索引大小，大到小的顺序排列 

  select indexrelname, pg_size_pretty(pg_relation_size(indexrelname))
    from pg_stat_user_indexes where
         schemaname = 'public' order by pg_relation_size(indexrelname) desc;

二、查看所有public schema里面表的大小，从大到小顺序排里 

  select relname, pg_size_pretty(pg_relation_size(relname))
    from pg_stat_user_tables where
         schemaname = 'public' order by pg_relation_size(relname) desc;

三、查看单个表的大小： 
    *  pg_relation_size('关系名') - 查看关系大小 

   mydb=# select pg_relation_size('contact'); 
   mydb=# select pg_size_pretty(pg_relation_size('contact'));