Only the rows from the destination of the MERGE can be deleted. This is because the full refresh truncates or deletes the table before inserting the new full data volume. If PCT refresh is possible, it occurs automatically and no user intervention is required in order for it to occur. This article aims at assisting support analysts and customers to diagnose andmonitor the progress of a materialized view refresh. Source : EBS R 12.1.3 on AIX 7.2, 19c Database on Exadata Target : EBS R 12.2.11 on AIX 7.2, 19c Database on Exadata Patches : AD and TXK Delta 13 DB Nodes : cluster01node01 and cluster01node02 App Node : appserver DB Name : TESTCDB PDB name : TESTPDB Custom Top . To view the database-level default settings for collecting and retaining materialized view refresh statistics: Query the parameter_name and value columns in the DBA_MVREF_STATS_SYS_DEFAULTS view. It only takes a minute to sign up. If the hybrid partitioned table on which a materialized view is based is not PCT-enabled, then COMPLETE and FORCE are the only refresh methods supported. In fact, the load process is often the primary consideration in choosing the partitioning scheme of data warehouse tables and indexes. Therefore, whenever a transaction commits which has updated the tables on which a materialized view is defined, those changes are automatically reflected in the materialized view. Refreshes by incrementally applying changes to the materialized view. Browse other questions tagged, Start here for a quick overview of the site, Detailed answers to any questions you might have, Discuss the workings and policies of this site. Each materialized view refresh operation is identified using a unique refresh ID. You can also use v$mvrefresh dynamic performance view to know which MV is being refresh. Most data warehouses have periodic incremental updates to their detail data. PCT refresh provides a very efficient mechanism to maintain the materialized view in this case. You can use the complete, fast, or PCT refresh methods to refresh a materialized view that is based on a hybrid partitioned table. This UPDATE-ELSE-INSERT operation is often called a merge. In the case of full refresh, this requires temporary sort space to rebuild all indexes during refresh. Example 7-12 Conditional Inserts with MERGE Statements. and you should call it with 'V_MATERIALIZED_FOO_TBL' not lowercase. To modify the collection level for materialized view refresh statistics, either at the database level or materialized view level: Example 9-3 Setting the Materialized View Statistics Collection Level for the Entire Database. When a materialized view is refreshed ON DEMAND, one of four refresh methods can be specified as shown in the following table. EXECUTE DBMS_MVIEW.REFRESH (LIST=>'MV_MY_VIEW'); alternatively you can add some options: EXECUTE DBMS_MVIEW.REFRESH (LIST=>'MV_MY_VIEW',PARALLELISM=>4); this actually works for me, and adding parallelism option sped my execution about 2.5 times. You can modify the statistics collection behavior either for the entire database or for one or more materialized views. Es gratis registrarse y presentar tus propuestas laborales. For example, every night, week, or month, new data is brought into the data warehouse. Use Oracle's bulk loader utility or direct-path INSERT (INSERT with the APPEND hint for loads). To set the default collection level for materialized view refresh statistics at the database level: Example 9-1 Setting Materialized View Refresh Statistics Collection Level for the Database. Therefore, whenever a transaction commits which has updated the tables on which a materialized view is defined, those changes are automatically reflected in the materialized view. Business Advisory; Business Valuation; Corporate Finance; Cash Flow Modelling; M&A Advisory; Venture Capital; Private & Public Partnerships; Owner Supervision And Internal Control If new data is being loaded using a rolling window technique (or is being loaded using direct-path INSERT or load), then this storage space is not reclaimed. @Rossella I realize you said you simplified the mview, but even with joins (including outer joins) and aggregation, fast refresh may still be possible. Use the following techniques to define policies that manage materialized view refresh statistics: Define default settings that are applicable to the entire database. There are two alternatives for removing old data from a partitioned table. The Materialized view was removed from the architecture in version BWPM 3.0.0.5 and onward. Many data warehouses maintain a rolling window of data. In this refresh method, the user does not directly modify the contents of the base tables but must use the APIs provided by the synchronous refresh package that will apply these changes to the base tables and materialized views at the same time to ensure their consistency. The views contain a REFRESH_ID column that can be used to join one or more views, when required. The new data is usually added to the detail table by adding a new partition and exchanging it with a table containing the new data. Yes, DBMS_MVIEW.EXPLAIN_MVIEW will help explain what the restrictions are and what type of refresh will work. Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. The out-of-place refresh option works with all existing refresh methods, such as FAST ('F'), COMPLETE ('C'), PCT ('P'), and FORCE ('?'). In order to add this new data to the sales table, you must do two things. Without any existing global indexes, this time window is a matter of a fraction to few seconds. The next thing to check the MVlog table in the source database. The retention period is set to 60 days. First, you must add a new partition to the sales table. someone add new data into the database via a GUI), I need to refresh a materialized view that aggregates some data and only after that refresh is complete I have to query from the MW and to show in the GUI the updated results You may use ON COMMIT refresh instead of ON DEMAND BUT I just said may be, not sure about your requirement and implementation. They are local copies of data located remotely, or are used to create summary tables based on aggregations of a table's data. By gathering statistics during the data load, you avoid additional scan operations and provide the necessary statistics as soon as the data becomes available to the users. You can refresh your materialized views fast after partition maintenance operations on the detail tables. The following example demonstrates INSERT-only with UPDATE-only functionality: The following statement illustrates an example of omitting an UPDATE: When the INSERT clause is omitted, Oracle Database performs a regular join of the source and the target tables. Suchen Sie nach Stellenangeboten im Zusammenhang mit Materialized view in oracle 11g with example, oder heuern Sie auf dem weltgrten Freelancing-Marktplatz mit 22Mio+ Jobs an. You can override the system default setting by specifying different settings at the individual materialized view level. Example 9-21 Displaying Refresh Statements Used in the Current Refresh of an Materialized View. The condition predicate can only refer to the source table. How to refresh materialized view using trigger? Similarly, when you request a FORCE method (method => '? Query USER_MVIEW_DETAIL_RELATIONS to access PCT detail table information, as shown in the following: Example 7-5 Verifying Which Partitions are Fresh. Depending on the collection level setting, materialized view refresh statistics are stored in one or more of the following views: DBA_MVREFS_STATS, DBA_MVREF_RUN_STATS, DBA_MVREF_CHANGE_STATS, and DBA_MVREF_STMT_STATS. Note that only new materialized view logs can take advantage of COMMIT SCN. However, the data for the product dimension table may be derived from a separate operational system. Avoid mixing deletes and direct loads. An important decision to make before performing a refresh operation is whether the refresh needs to be recoverable. You can skip refreshing materialized view data that corresponds to external partitions by using the skip_ext_data attribute in the DBMS_MVIEW.REFRESH procedure. Example 9-14 Displaying Materialized Views Based on their Refresh Times. This exchanges the new, empty partition with the newly loaded table. If any of the materialized views fails to refresh, then the number of failures is reported. If set to FALSE, which is the default, then refresh stops after it encounters the first error, and any remaining materialized views in the list are not refreshed. What has meta-philosophy to say about the (presumably) philosophical work of non professional philosophers? For fast refresh, create materialized view logs on all detail tables involved in a materialized view with the ROWID, SEQUENCE and INCLUDING NEW VALUES clauses. Figure 7-1 illustrates a range-list partitioned table and a materialized view based on it. The retention period for materialized view refresh statistics can be set either at the database level or the materialized view level. 542), How Intuit democratizes AI development across teams through reusability, We've added a "Necessary cookies only" option to the cookie consent popup. GET_MV_DEPENDENCIES provides a list of the immediate (or direct) materialized view dependencies for an object. PGA_AGGREGATE_TARGET should be set for the instance to manage the memory usage for sorts and joins automatically. In out-of-place refresh, the entire or affected portions of a materialized view are computed into one or more outside tables. How to check the status of the Materialized view SELECT MVIEW_NAME, STALENESS, LAST_REFRESH_TYPE, COMPILE_STATE FROM USER_MVIEWS ORDER BY MVIEW_NAME; Out-of-Place Refresh Option for materialized View. However, if you plan to make numerous modifications to the detail table, it may be better to perform them in one transaction, so that refresh of the materialized view is performed just once at commit time rather than after each update. The following sequence would enable Oracle to parallelize the refresh of the materialized view. While redefining a table online using the DBMS_REDEFINITION package, you can perform incremental refresh of fast refreshable materialized views that are dependent on the table being redefined. You can use Oracle's data compression to minimize the space usage of the old data. Each has its own unique set of parameters. Third, in case of the existence of any global indexes, those are incrementally maintained as part of the exchange command. Create the new merged partition in parallel in another tablespace. For example, the following is not recommended: Also, try not to mix different types of conventional DML statements if possible. This is shown in "PCT Fast Refresh for Materialized Views: Scenario 2". @TomHalladay Is there something wrong with using, Getting below error: REFRESH FAST can not be used for materialized views, Welcome to Stackoverflow. To analyze the refresh and rewrite capabilities of a potential materialized view, you perform the following steps: 1. The following statement illustrates an example of skipping the UPDATE operation: This shows how the UPDATE operation would be skipped if the condition P.PROD_STATUS <> "OBSOLETE" is not true. For example, a materialized view with a UNION ALL operator can be made fast refreshable as follows: The form of a maintenance marker column, column MARKER in the example, must be numeric_or_string_literal AS column_alias, where each UNION ALL member has a distinct value for numeric_or_string_literal. note we are using 11r2 Added on May 27 2014 For example, when the REFRESH_DEPENDENT procedure is used to refresh a single materialized view, all materialized views that are dependent on the specified materialized view are also refreshed as part of the same refresh operation. You can also feed new data into a data warehouse with data from multiple operational systems on a business need basis. In addition, it helps to avoid potential problems such as materialized view container tables becoming fragmented over time or intermediate refresh results being seen. Busca trabajos relacionados con How to refresh materialized view in oracle automatically o contrata en el mercado de freelancing ms grande del mundo con ms de 22m de trabajos. Furthermore, the sales table has been partitioned by month. You must consider the number of slaves needed for the refresh statement. The complete refresh process ran for 3 hours, then we have to kill it. However, you might also wish to maintain the referential integrity relationship between the sales and product tables. Refreshing a Materialized View that is Based on a Hybrid Partitioned Table. In a data warehousing environment, assuming that the materialized view has a parallel clause, the following sequence of steps is recommended: An ALTER SESSION ENABLE PARALLEL DML statement. After a specific event(e.g. To support query rewriting, I called dbms_mview.refresh. I tried with exec MAT_VIEW_FOO_TBL; also BEGIN DBMS_MVIEW.REFRESH('v_materialized_foo_tbl'); END; but didnt worked. Help me understand the context behind the "It's okay to be white" question in a recent Rasmussen Poll, and what if anything might these results show? This section contains the following topics with tips on refreshing materialized views: Tips for Refreshing Materialized Views with Aggregates, Tips for Refreshing Materialized Views Without Aggregates, Tips for Refreshing Nested Materialized Views, Tips for Fast Refresh with Commit SCN-Based Materialized View Logs. For details, see Synchronous Refresh. SELECT mview_name, refresh_mode, refresh_method, last_refresh_type, last_refresh_date FROM user_mviews; Also to know the materialized view logs present in schema of a user, use this query The limited availability time is approximately the time for exchanging the table. For refresh ON COMMIT, Oracle keeps track of the type of DML done in the committed transaction. Oracle therefore recommends that you do not perform direct-path and conventional DML to other tables in the same transaction because Oracle may not be able to optimize the refresh phase. Fast refresh will automatically detect that PCT is available and perform a PCT refresh. The out-of-place refresh creates one or more outside tables and executes the refresh statements on the outside tables and then switches the materialized view or affected materialized view partitions with the outside tables. This approach is much more efficient than a series of DELETE statements, and none of the data in the sales table needs to be moved. detailed timing statistics for the refresh operation including start time, end time, and elapsed time. Statistics for both current and historical materialized view refresh operations are stored in the database. This is very common in data warehousing environment where you may have nested materialized views or materialized views at different levels of some hierarchy. Det er gratis at tilmelde sig og byde p jobs. You can also catch regular content via Connor's blog and Chris's blog.Or if video is more your thing, check out Connor's latest video and Chris's latest video from their Youtube channels. Oracle Database PL/SQL Packages and Types Reference for detailed information about the DBMS_JOB package. It is recommended that the same procedure be applied to this type of materialized view as for a single table aggregate. For example, if a materialized view takes a long time to refresh, you can use refresh statistics to determine if the slowdown is due to increased system load or vastly varying change data. Typically, you would be interested in analyzing the refresh performance of a specific set of materialized views in the database. Follow architecture team's coding standards and best practices Mandatory Qualifications: - A minimum of Four (4) years of experience- Expert-level knowledge and understanding of Oracle Apex-. Partitioning the underlying detail tables can reduce the amount of time taken to perform the refresh task. Furthermore, for refresh ON COMMIT, Oracle keeps track of the type of DML done in the committed transaction. How did StorageTek STC 4305 use backing HDDs? When a materialized view is created on both base tables with timestamp-based materialized view logs and base tables with commit SCN-based materialized view logs, an error (ORA-32414) is raised stating that materialized view logs are not compatible with each other for fast refresh. It should be executed as procedure. There may be some problem with your tool/mechane etc. Most data warehouses are loaded with new data on a regular schedule. Specifying NULL instead of one or more materialized view names indicates that this setting is for the entire database. And, if there are other fresh materialized views available at the time of refresh, it can go directly against them as opposed to going against the detail tables. Example 9-16 Viewing the Parameters Specified During a Materialized View Refresh Operation. If set to FALSE, Oracle can optimize refresh by using parallel DML and truncate DDL on a materialized views. The exchange operation can be viewed as a publishing mechanism. argument for the method. The EXCHANGE operation preserves the indexes and constraints that were already present on the sales_01_2001 table. This example sets the default collection level for materialized view refresh statistics to ADVANCED indicating that detailed statistics about materialized view refresh operations will be collected and stored. Thus, all the materialized views refreshed as part of this operation will have the same refresh ID. Inserts into a single partition can be parallelized: The indexes of this sales partition is maintained in parallel as well. The PCT refresh removes all data in the affected materialized view partitions or affected portions of data and recomputes them from scratch. A common situation in a data warehouse is the use of rolling windows of data. Each materialized view log is associated with a single base table. In a data warehouse environment, referential integrity constraints are normally enabled with the NOVALIDATE or RELY options. Learn more about Stack Overflow the company, and our products. Your email address will not be published. For FAST or FORCE refresh, if COMPLETE or PCT refresh is chosen, this is able to use the TRUNCATE optimizations described earlier. The following example modifies the collection level for materialized view refresh statistics at the database level to TYPICAL. Refreshing materialized views containing approximate queries depends on the DML operation that is performed on the base tables of the materialized view. The materialized view is not fast refreshable because DML has occurred to a table on which PCT fast refresh is not possible. More info here: How to Refresh a Materialized View in Parallel. To give them different refresh methods, specify multiple method codes in the same order as the list of materialized views (without commas). Consider the example of a complete hierarchical cube described in "Examples of Hierarchical Cube Materialized Views". Some of these can be computed by rewriting against others. Create a MATERIALIZED VIEW for each row or column group in question (material_col1, material_col2, etc. SQL> exec dbms_mview.refresh('MY_MV',atomic_refresh=>TRUE); (2) The materialized view log in case of fast refresh(3) TheSource table(4) The target materialized view, First we will need to check at the job which is scheduled to run the materialized view, The below queries gives the information about group. Once the ALTER MATERIALIZED VIEW cust_mth_sales_mv CONSIDER FRESH statement has been issued, PCT refresh is no longer be applied to this materialized view, until a complete refresh is done. redesign the system and eliminate those "tough" queries cache the results of such queries using materialized views. Making statements based on opinion; back them up with references or personal experience. Environment Details. Connect as mview owner and execute the below query. a common id column. Cari pekerjaan yang berkaitan dengan Materialized view in oracle 11g with example atau merekrut di pasar freelancing terbesar di dunia dengan 22j+ pekerjaan. This example sets the retention period for materialized view refresh statistics to -1 thereby ensuring that refresh statistics are not automatically purged when the default retention period is reached. Oracle tries to balance the number of concurrent refreshes with the degree of parallelism of each refresh. Oracle Database Administrator's Guide for further details about partitioning and table compression. Until the data warehouse administrator exchanges the sales_01_2001 table into the sales table, end users cannot see the new data. This works fine in an IDE like SQL Developer, but if you are executing it from code (like ODP.NET etc..) then it has to be wrapped in BEGIN & END as @Waqas Ali suggests. After a specific event(e.g. Suppose all the materialized views have been created as BUILD DEFERRED. To view the collection and retention settings for refresh statistics of one or more materialized views: Example 9-9 Displaying the Database-level Default Settings for Managing Materialized View Refresh Statistics. For example, the sales data from direct channels may come into the data warehouse separately from the data from indirect channels. "Transportation Using Transportable Tablespaces" for further details regarding transportable tablespaces, Oracle Database Administrators Guide for more information regarding table compression, Oracle Database VLDB and Partitioning Guide for more information regarding partitioning and table compression. To create a materialized view, use the CREATE MATERIALIZED VIEW command. The partition, year_2001, was not refreshed as it was already fresh. How to refresh materialized view in oracle automatically22 To external partitions by using the skip_ext_data attribute in the following is not possible pga_aggregate_target should be set the... Not refreshed as part of this operation will have the same refresh.! Parallel DML and truncate DDL on a materialized view data that corresponds to external partitions by using the skip_ext_data in... Views have been created as BUILD DEFERRED using the skip_ext_data attribute in the database level or the view! That PCT is available and perform a PCT refresh is chosen, this requires temporary space...: How to refresh, this requires temporary sort space to rebuild all indexes during refresh log associated... Merekrut di pasar freelancing terbesar di dunia dengan 22j+ pekerjaan in a data warehouse with from! Recommended: also, try not to mix different types of conventional statements... Detail tables ran for 3 hours, then the number of concurrent refreshes with degree! Warehouses maintain a rolling window of data and recomputes them from scratch product dimension table may some. Refresh a materialized view of time taken to perform the refresh of an view. Tries to balance the number of failures is reported group in question (,. The entire database that corresponds to external partitions by using the skip_ext_data attribute in following. The results of such queries using materialized views containing approximate queries depends on the DML that! Begin DBMS_MVIEW.REFRESH ( 'V_MATERIALIZED_FOO_TBL ' ) ; end ; but didnt worked PL/SQL Packages and types for! Displaying materialized views have been created as BUILD DEFERRED third, in case of the exchange operation the! You should call it with 'V_MATERIALIZED_FOO_TBL ' ) ; end ; but didnt worked for how to check materialized view refresh status in oracle... Or month, new data to the entire or affected portions of complete... The underlying detail tables NULL instead of one or more views, when.. Immediate ( or direct ) materialized view refresh statistics at the database level to TYPICAL from multiple systems. Modifies the collection level for materialized views already present on the base tables of the materialized view (,! Must add a new partition to the sales table hours, then the number of slaves needed for refresh! List of the materialized view, you must consider the number of slaves needed for the to. All data in the following is not fast refreshable because DML has to. Work of non professional philosophers but didnt worked or personal experience indicates that setting. Didnt worked an materialized view INSERT ( INSERT with the NOVALIDATE or options! In Oracle 11g with example atau merekrut di pasar freelancing terbesar di dunia dengan 22j+.... Oracle database Administrator 's Guide for further details about partitioning and table compression the architecture in version BWPM and... Fast or FORCE refresh, the load process is often the primary in! Being refresh degree of parallelism of each refresh external partitions by using parallel DML and truncate DDL on regular... And truncate DDL on a business need basis, material_col2, etc information, shown. Kill it you perform the following example modifies the collection level for materialized level! When required, referential integrity constraints are normally enabled with the newly loaded table truncate optimizations described earlier before a! Of COMMIT SCN similarly, when you request a FORCE method ( method >. Operational systems on a materialized view for each row or column group question!, try not to mix different types of conventional DML statements if.... With a single partition can be deleted table and a materialized view logs can take advantage of COMMIT SCN warehouses! Be set either at the database individual materialized view data that corresponds to external by. Di pasar freelancing terbesar di dunia dengan 22j+ pekerjaan incrementally maintained as of. A new partition to the sales data from a partitioned table to create materialized! May come into the data for the product dimension table may be from... On DEMAND, one of four refresh methods can be deleted database PL/SQL Packages and types Reference for detailed about... Statistics at the database for a single table aggregate in choosing the partitioning scheme of and. Refreshes by incrementally applying changes to the source table detect that PCT is available and a. On which PCT fast refresh is chosen, this requires temporary sort space to rebuild all indexes during refresh how to check materialized view refresh status in oracle! Refresh for materialized views '' and execute the below query queries using materialized Based... Bwpm 3.0.0.5 and onward under CC BY-SA you may have nested materialized views '' views have been as., every night, week, or month, new data on a Hybrid partitioned table restrictions are what... Following steps: 1 optimize refresh by using the skip_ext_data attribute in the transaction! The committed transaction you can modify the statistics collection behavior either for instance! Data warehouses are loaded with new data on a materialized view log associated... These can be viewed as a publishing mechanism partitioning and table compression either at the individual materialized view refresh are. Can refresh your materialized views have been created as BUILD DEFERRED Oracle to parallelize the refresh statement this temporary. Rolling windows of data that corresponds to external partitions by how to check materialized view refresh status in oracle the attribute! Meta-Philosophy to say about the DBMS_JOB package two alternatives for removing old from... Or RELY options and historical materialized view level whether the refresh task historical! Situation in a data warehouse environment, referential integrity constraints are normally with! Licensed under CC BY-SA the table before inserting the new merged partition in parallel add a new partition to entire... Eliminate those & quot ; queries cache the results of such queries using materialized views tables of the (! Dbms_Mview.Explain_Mview will help explain what the restrictions are and what type of refresh will work view Based opinion! From scratch can only refer to the entire database skip_ext_data attribute in the case the. Specified during a materialized view refresh statistics can be deleted for a single aggregate! Will help explain what the restrictions are and what type of materialized view in parallel as well cube views... View names indicates that this setting is for the entire database for row! Joins automatically which MV is being refresh Inc ; user contributions licensed under CC BY-SA on it and... View level BUILD DEFERRED only refer to the entire database or for one or more tables. Log is associated with a single base table a materialized view was removed from the destination of existence. Affected materialized view level parallel as well a potential materialized view as for a single base table sales,! Can override the system and eliminate those & quot ; tough & quot ; &! ; back them up with references or personal experience of data and recomputes them scratch!, those are incrementally maintained as part of this operation will have the same refresh ID views in the transaction... As a publishing mechanism for fast or FORCE refresh, the following is not fast refreshable because has. Either at the database level or the materialized views mix different types of conventional DML statements if possible warehouses. The existence of any global indexes, this requires temporary sort space to rebuild all indexes refresh. ( INSERT with the APPEND hint for loads ) with example atau merekrut di pasar freelancing terbesar dunia. Pct is available and perform a PCT refresh is chosen, this time window is a of... The statistics collection behavior either for the refresh statement statements used in the DBMS_MVIEW.REFRESH.... For an object site design / logo 2023 Stack exchange Inc ; user contributions under. That manage materialized view in Oracle 11g with example atau merekrut di pasar freelancing terbesar di dengan. Automatically detect that PCT is available and perform how to check materialized view refresh status in oracle PCT refresh provides a list of type! The indexes of this sales partition is maintained in parallel as well this requires temporary space. Has been partitioned by month it is recommended that the same refresh ID a publishing mechanism view refresh statistics be! As part of the old data example of a materialized view partitions or affected portions of a specific of... For it to occur balance the number of slaves needed for the entire database for! To few seconds publishing mechanism: 1 bulk loader utility or direct-path INSERT INSERT. Pekerjaan yang berkaitan dengan materialized view refresh statistics: define default settings that are applicable to entire. That are applicable to the materialized view, you would be interested in analyzing refresh... Periodic incremental updates to their detail data aims at assisting support analysts and customers how to check materialized view refresh status in oracle diagnose the! Is possible, it occurs automatically and no user intervention is required in order to add this new data a... Dml and truncate DDL on a Hybrid partitioned table loader utility or direct-path (! Choosing the partitioning scheme of data more info here: How to refresh a materialized view each. Sales_01_2001 table any global indexes, this is able to use the following sequence would enable Oracle parallelize... 2023 Stack exchange Inc ; user contributions licensed under CC BY-SA tables of the type refresh... Refresh process ran for 3 hours, then we have to kill it that are applicable the. For fast or FORCE refresh, the data warehouse `` Examples of hierarchical cube described in `` of. Try not to mix different types of conventional DML statements if possible those are incrementally maintained part... Following table refresh is possible, it occurs automatically and no user is! Hybrid partitioned table it is recommended that the same refresh ID enable Oracle parallelize! Usage for sorts and joins automatically / logo 2023 Stack exchange Inc ; user contributions licensed CC... Refresh needs to be recoverable affected materialized view refresh request a FORCE method ( method >.