Oracle中的物化视图(Materialized View)是一种特殊的视图,它存储了查询结果的数据,而不是像普通视图那样仅存储查询的定义。物化视图允许用户对大型数据集进行预先计算和存储,从而提高了查询性能,尤其是在需要频繁访问相同数据集的情况下。 创建物化视图的基本语法 创建物化视图的基本语法如下: sql CREATE MATERIALIZED VIE...
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 CREATEMATERIALIZEDVIEWview_name[column_list][table_option_list][partition_option][refresh_clause]ASview_select_stmt;column_list:(column_name[,column_name...])refresh_clause: REFRESH[COM...
Oracle Database - Enterprise Edition - Version 11.2.0.2 and later: Create Materialized View Results in ORA-955 But Drop Materialized View Does Not Succeed Either
When you create a materialized view, Oracle Database creates one internal table and at least one index, and may create one view, all in the schema of the materialized view. Oracle Database uses these objects to maintain the materialized view data. You must have the privileges necessary to cr...
Oracle Create or Replace Materialized Views A materialized view in Oracle is a database object that contains the results of a query. It is a replica of a target master table or master materialized view, which isrefreshed periodically to keep the data consistent. By storing the computed results...
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 LOG ON [schema.] table [parallel_clause] [with_clause] [mv_log_purge_clause]; parallel_clause: NOPARALLEL | PARALLEL integer with_clause: WITH [ {PRIMARY KEY | ROWID | SEQUENCE} [ { ,...
materialized_view 作成するマテリアライズド・ビューの名前を指定します。名前は、「データベース・オブジェクトのネーミング規則」に指定されている要件を満たしている必要があります。Oracle Databaseは、マテリアライズド・ビュー名に接頭辞または接尾辞を追加して、マテリアライズド・...
Oracle Database Cloud Schema Service - Version N/A and later: ORA-01031: Insufficient Privileges When Create a Mview in Different Schema
CREATE/ALTER/DROP MATERIALIZED VIEW LOG CREATE MATERIALIZED VIEW LOG ON [schema.] tablename [ Physical_Attributes_Clause] [TABLESPACE tablespace] [STORAGE Storage_Clause] Creates a materialized view log, which is a … - Selection from Oracle SQL: the Es
CREATE MATERIALIZED VIEW EmpSummary AS SELECT DepartmentID, COUNT(*) AS NumEmployees, AVG(Salary) AS AvgSalary FROM Employees GROUP BY DepartmentID; 此语句创建了一个名为EmpSummary的物化视图,存储每个部门的员工数量和平均工资。物化视图可以定期刷新以保持数据的最新状态。