openGauss每日一练第 10天

1、创建表空间t_tbspace、用户test，并使用test，在这个表空间上创建表t1

create tablespace t_tbspace relative location 'tablespace/t_tbspace';
create user test identified by 'zuoye@1234';grant create on tablespace t_tbspace to test;\c omm testcreate table t1 (col1 char(20) ) tablespace t_tbspace;

2、查看表空间t_tbspace的oid和大小

select oid from pg_tablespace;select pg_tablespace_size('t_tbspace');

3、查看数据库在默认表空间下有哪些对象

with objectInDefaultTS as
          ( select relname, relkind, relpages,pg_size_pretty(pg_relation_size(a.oid)),
                  reltablespace,relowner
            from pg_class a
            where a.relkind in ('r', 'i')  and reltablespace='0'
         )
 select * 
 from objectInDefaultTS 
   where relname not like 'pg_%' and relname not like 'gs_%' and relname not like 'sql_%'
 order by relpages desc;

4、查看数据库在非默认表空间下有哪些对象

select relname,relkind,relpages,pg_size_pretty(pg_relation_size(a.oid)),
          reltablespace,relowner
   from pg_class a, pg_tablespace tb
   where a.relkind in ('r', 'i')
   and a.reltablespace=tb.oid
   and tb.spcname='t_tbspace'
   order by a.relpages desc;

5、重命名表空间

ALTER TABLESPACE t_tbspace RENAME TO zuoye_tbs;

6、删除表空间

drop table t1;
drop tablespace zuoye_tbs;