postgres 查看数据表和索引的大小

    *  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;

    * 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;

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

   GZ125=# select pg_relation_size('contact');
   GZ125=# select pg_size_pretty(pg_relation_size('contact'));
   

FROM：
http://www.91linux.com/html/article/database/PostgreSQL/20080523/11362.html