Error:Errorwhilecompiling statement: FAILED: SemanticException [Error10265]: This commandisnotallowedonan ACID table ods.u_data_newwitha non-ACID transaction manager. Failed command: create materialized view week_pv_materializedasselectweekday,count(1)fromods.u_data_newgroupbyweekday (state=42000,code...
In such cases, we must be able to create a virtual table that can only display the required attributes from a table. This is possible via View and Materialized View which we will discuss in this article. We will also discuss the differences between view and materialized View with the help ...
存储方式不同:普通视图只是一个命名的查询结果集,不存储数据,每次查询都会重新执行查询语句;而Materialized View会将查询结果集存储在磁盘上,可以定期刷新数据,提高查询性能。 查询性能不同:由于Materialized View存储了查询结果集,因此查询时不需要再重新执行查询语句,可以提高查询性能;而普通视图每次查询都需要重新执行查询...
View can be defined as a virtual table created as a result of the query expression. However, Materialized View is a physical copy, picture or snapshot of the base table. A view is always updated as the query creating View executes each time the View is used. On the other hands, Materia...
which is best materialized view or table with SP? and why?Reply SCD type 6 in sql About Us Contact Us Privacy Policy Terms Media Kit Sitemap Report a Bug FAQ Partners C# Tutorials Common Interview Questions Stories Consultants Ideas Certifications CSharp TV Web3 Universe Build with JavaScript...
实例化视图实际用的时候有点像单独的表，是定期从table里面更新出来的，view是直接去表里面查的，性能差很多，materialized view查询快，并且不会影响表的使用，不会对表产生共享锁，但是建立和更新慢，并且不是实时更新的 MV
create table t(id int,name varchar); 插入数据: insert into t -> select generate_series(1,1000000),random()::VARCHAR; 创建一个:物化视图 create materialized view mv_t as select * from t; 创建一个索引: create unique index idx_ken on mv_t(id); ...
materialized view(MV)是自动刷新或者手动刷新的，View不用刷新 MV也可以直接update，但是不影响base table，对View的update反映到base table上 MV主要用于远程数据访问，mv中的数据需要占用磁盘空间，view中不保存数据 materialized
创建物化视图需要有 CREATE TABLE 权限。更多有关 OceanBase 数据库权限的详细介绍,请参见 Oracle 模式下的权限分类。语法CREATE MATERIALIZED VIEW view_name [column_list] [table_option_list] [partition_option] [refresh_clause] AS view_select_stmt; column_list: (column_name [, column_name ...]) ...
A table is a database structure storing data in rows and columns, whereas a view is a virtual table resulting from a predefined SQL query.