CREATE MATERIALIZED VIEW [ IF NOT EXISTS ] table_name [ (column_name [, ...] ) ] [ WITH ( storage_parameter [= value] [, ... ] ) ] [ TABLESPACE tablespace_name ] AS query [ WITH [ NO ] DATA ] 2、删除视图 1 DROP MA
描并且在REFRESH MATERIALIZED VIEW被使用前不能被查询。 在该命令被发出时,查询会被执行并且被用来填充该视图(除非使用了 WITH NO DATA),并且后来可能会用 REFRESHMATERIALIZED VIEW进行刷新。 CREATE MATERIALIZED VIEW类似于 CREATE TABLE AS,不过它还会记住被用来初始化该视图的查询, 这样它可以在后来被命令刷新。
create unique index index_name on view_name (列名1,列名2...);三、删除物化视图 drop materialized view [if exists] view_name;四、修改物化视图 ALTER MATERIALIZED VIEW [ IF EXISTS ] name action [, ... ]ALTER MATERIALIZED VIEW [ IF EXISTS ] name RENAME [ COLUMN ] column_name TO new_...
HINT: Create a unique index with no WHERE clause on one or more columns of the materialized view. mytest=# create unique index uidx_mv_id on mv_t1_t2 (t1_id ); mytest=# REFRESH MATERIALIZED VIEW CONCURRENTLY mv_t1_t2 WITH DATA; mytest=# insert into t1 values (12,'xx','yy');...
Understanding PostgreSQL views and materialized views is key to using the database effectively. Learn the difference between views and materialized views here!
However, to refresh it with CONCURRENTLY option, you need to create a UNIQUE index for the view first. CREATE UNIQUE INDEX rental_category ON rental_by_category (category); Let’s refresh data concurrently for the rental_by_category view. REFRESH MATERIALIZED VIEW CONCURRENTLY rental_by_category...
在PostgreSQL数据库中,物化视图(Materialized View)提供了对数据的快速访问,但其使用和管理需特别注意。物化视图不能直接被更新,而是通过解析器将其视为一个关系,如同表或视图。引用《PostgreSQL11.2-中文手册》,物化视图用于存储对查询结果的快速访问,而非直接更新数据源。因此,当引用物化视图时,...
只有当物化视图中存在unique index的时候,refresh物化视图才能使用增量更新,加入concurrently参数。否则报错。 mytest=# REFRESH MATERIALIZED VIEW CONCURRENTLY mv_t1_t2 WITH DATA; ERROR: cannot refresh materialized view "public.mv_t1_t2" concurrently
CREATE UNIQUE INDEX sel_eth_txn_info_recent_30_day_id ON sel_eth_txn_info_recent_30_day(id); 更新数据 REFRESH MATERIALIZED VIEW CONCURRENTLY sel_eth_txn_info_recent_30_day; -- 边刷新、边查REFRESH MATERIALIZED VIEW sel_eth_txn_info_recent_30_day; ...
warehouse_db=# create table tab_view(emp_id int not null,emp_name varchar(10),emp_city varchar(10)); CREATE TABLE warehouse_db=# insert into tab_view values (1,'Adam','Chicago'); INSERT 0 1 warehouse_db=# insert into tab_view values (2,'John','Miami'),(3,'Smith','Dallas')...