一般来说,现在为了各司其职,都把硬盘做成了san,raid,至少lvm。但是仍然有一些用户希望可以指定表空间和索引。在lightdb里面也支持该特性。如下:
lightdb@postgres=# create tablespace tab_tbs location '/data1/cn/tab_tbs'; WARNING: tablespace location should not be inside the data directory ERROR: directory "/data1/cn/tab_tbs" does not exist lightdb@postgres=# create tablespace tab_tbs location '/data1/cn/'; WARNING: tablespace location should not be inside the data directory CREATE TABLESPACE lightdb@postgres=# create table tab_for_tbs(id int) tablespace tab_tbs; CREATE TABLE lightdb@postgres=# \dS+ tab_for_tbs Table "public.tab_for_tbs" Column | Type | Collation | Nullable | Default | Storage | Stats target | Description --------+---------+-----------+----------+---------+---------+--------------+------------- id | integer | | | | plain | | Tablespace: "tab_tbs" Access method: heap
这样就在tab_tbs下创建了表。
索引也是一样的,如下:
lightdb@postgres=# create index idx_tab_for_tbs on tab_for_tbs(id) tablespace tab_tbs; CREATE INDEX
需要注意的是,在lightdb-x分布式版本中,表空间属性不支持透传到DN节点。索引不能声明tablespace xxx子句,如下:
lightdb@postgres=# \dS+ tab_for_tbs_103402 Table "public.tab_for_tbs_103402" Column | Type | Collation | Nullable | Default | Storage | Stats target | Description --------+---------+-----------+----------+---------+---------+--------------+------------- id | integer | | | | plain | | Access method: heap lightdb@postgres=# create index idx_tab_for_tbs on tab_for_tbs(id) tablespace tab_tbs; ERROR: specifying tablespaces with CREATE INDEX statements is currently unsupported
注:虽然如此,一般来说,我们是强烈建议数据文件,WAL日志,临时文件目录分开的。
标签:index,lightdb,create,tablespace,tab,tbs,postgres From: https://www.cnblogs.com/zhjh256/p/16585201.html