索引相关操作

• 建立索引。

postgres=# create unique index tbase_id_uidx on tbase(id);
CREATE INDEX
postgres=# create index tbase_mc_idx on tbase(mc);     
CREATE INDEX
postgres=# 

• \di查看索引列表。

postgres=# \di
                              List of relations
 Schema |    Name      | Type | Owner | Table 
--------+---------------+-------+-------+-------
 public | tbase_id_uidx | index | tbase  | tbase
 public | tbase_mc_idx  | index | tbase  | tbase
(2 rows)

• \di+查看索引列表详细信息（包含注释），占用空间大小--只能在dn上面查看索引大小。

postgres=# \di+
                              List of relations
 Schema |    Name      | Type  | Owner | Table |    Size   |  Description  
--------+---------------+-------+-------+-------+------------+---------------
 public | tbase_id_uidx | index | tbase  | tbase | 8192 bytes | tbase唯一索引
 public | tbase_mc_idx      | index | tbase  | tbase     | 8192 bytes | 
(2 rows)

• \di+显示某个模式下的所有索引--只能在dn上面查看索引大小。

postgres=# \di+ public.*
                              List of relations
 Schema |    Name      | Type  | Owner | Table |    Size   |  Description  
--------+---------------+-------+-------+-------+------------+---------------
 public | tbase_id_uidx | index | tbase  | tbase | 8192 bytes | tbase唯一索引
 public | tbase_mc_idx      | index | tbase  | tbase     | 8192 bytes | 
(2 rows)

• \di+索引名显示某个索引的详细信息--只能在dn上面查看索引大小。

postgres=# \di+ public.tbase_id_uidx
                              List of relations
 Schema |    Name      | Type  | Owner | Table |    Size   |  Description  
--------+---------------+-------+-------+-------+------------+---------------
 public | tbase_id_uidx | index | tbase  | tbase | 8192 bytes | tbase唯一索引
(1 row)

• \di+通配符列出适配的索引--只能在dn上面查看索引大小。

postgres=# \di+ *idx
                              List of relations
 Schema |    Name      | Type  | Owner | Table |    Size   |  Description  
--------+-------------------+-------+-------+------------+------------+---------------
 pgxc   |order_main_id_idx | index | tbase  |order_main | 8192 bytes | 
 public | tbase_id_uidx | index | tbase  | tbase | 8192 bytes | tbase唯一索引
 public | tbase_mc_idx      | index | tbase  | tbase     | 8192 bytes | 
(3 rows)

postgres=# \di+ *uidx--#只能在dn上面查看索引大小
                              List of relations
 Schema |    Name      | Type  | Owner | Table |    Size   |  Description  
--------+---------------+-------+-------+-------+------------+---------------
 public | tbase_id_uidx | index | tbase  | tbase | 8192 bytes | tbase唯一索引
(1 row)