Cannot refresh materialized view concurrently. This Postgres 9. The command to About Refresh Modes for Materialized Views When creating a materialized view, you have the option of specifying whether the refresh occurs ON DEMAND or ON COMMIT. A search of the source code shows that ExecRefreshMatView take an ACCESS EXCLUSIVE lock, as you might expect, so no other queries may run on the view. Dec 28, 2024 · Hi Team, The option "Refresh MATERIALIZED VIEW WITH NO DATA Concurrently" is erroneously displayed in the pgAdmin interface, as shown in the attached screenshot. May 14, 2020 · Concurrent refreshes of materialized views don't have a record in pg_stat_activity, other than the initial (~immediately completing) query to start them. Refreshing materialized view without the concurrently keyword runs just fine. sql & structure. 3 have a severe limitation consisting in using an exclusive lock when refreshing it. To determine whether the materialized view received an incremental or full refresh, use SVL_MV_REFRESH_STATUS. This option may be faster in cases where a small number of rows are Concurrent refresh Queries can read the view even when the view is getting refreshed as the update can be performed concurrently in the background. This option is only permitted when there is at least one UNIQUE index on the materialized view, and when the materialized view is populated. 6 days ago · The goal is to update the materialized view while minimizing downtime and allowing read access. This issue appeared after upgrade from v 11 to 13. 旧的内容会被抛弃。如果指定了 WITH DATA （或者作为默认值），支持查询将被执行以 提供新的数据，并且会让物化视图将处于可扫描的状态。如果指定了 WITH NO DATA，则不会生成新数据并且会让物化 Jul 22, 2013 · Add support for REFRESH MATERIALIZED VIEW CONCURRENTLY. Mar 10, 2023 · The documentation describes the CONCURRENTLY option of REFRESH MATERIALIZED VIEW: Without this option a refresh which affects a lot of rows will tend to use fewer resources and complete more quickly, but could block other connections which are trying to read from the materialized view. yaml. The reason is that PostgreSQL uses temporary tables internally when refreshing materialized views concurrently, and the user might be missing necessary permissions. The initial build can be parallelized by increasing the number of threads specified by the property concurrent_materialized_view_builders in cassandra. This unique index acts as a lookup table while the table is refreshing. A “materialized view” is a database object which stores the result of a precalculated database query and makes it easy to refresh this result as needed. This method is simple to implement and will help you keep your data up-to-date without having to manually refresh the views. Feb 3, 2025 · REFRESH MATERIALIZED VIEW CONCURRENTLY recent_product_sales; Materialized views that generate columns with non-unique values cannot use unique indexes - and cannot use the concurrent refresh option. This option may be faster in cases where a small number of rows are affected. Per the manual. This option may be faster in cases where a small number of rows are Dec 17, 2015 · 6 PostgreSQL 9. The upcoming version of Postgres is adding many basic things like the possibility to create, manage and refresh a materialized views. With the views Sep 20, 2018 · VACUUM will remove the dead rows, but it cannot reduce the bloat (that can be done with VACUUM (FULL), but that would lock the view just like REFRESH MATERIALIZED VIEW without CONCURRENTLY). Without this option a refresh which affects a lot of rows will tend to use fewer resources and complete more quickly, but could block other connections which are trying to read from the materialized view. Summary There’s always additional considerations with indexing. schedule, include the CONCURRENTLY option: Dec 1, 2018 · This occurs inside of pg, without rails. This Mar 12, 2018 · EXCLUSIVE ", meaning that another REFRESH MATERIALIZED VIEW CONCURRENTLY statement, which requests the same EXCLUSIVE lock, will have to wait until the earlier EXCLUSIVE lock is released. Mar 27, 2024 · I'm encountering a syntax error when attempting to refresh a materialized view concurrently in Azure Flexible Server for PostgreSQL v11. Apr 1, 2025 · Learn how to efficiently use materialized views in PostgreSQL to optimize complex queries and enhance database performance. The original view remains available for read operations throughout the process, making this approach ideal for environments where downtime Aug 25, 2021 · demo=# REFRESH MATERIALIZED VIEW CONCURRENTLY mat_view; ERROR: cannot refresh materialized view "public. Any idea why the query waits? Aug 23, 2019 · I have a materialized view my_view which selects values from different tables. This allows reads to continue without any blocking while a REFRESH runs. 4の新機能のうち、postgresql. materialized_view_example” concurrently HINT: Create a unique index with no WHERE clause on one or more columns of the materialized view. Learn how to fix the cannot refresh materialized view concurrently error with this comprehensive guide. confを使った設定変更の方法や、pg_prewarm、 MATERIALIZED VIEWのCONCURRENTLYオプションなど、主にPostgreSQL環境を運用する際に関係する改善点を中心に紹介します。 Mar 3, 2022 · I have discovered a bug where a column name called “mv” in a materialized view cannot be refreshed concurrently due to an internal PostgreSQL table alias also named “mv”. If you anticipate performing insert, update or delete operations on tables referenced by a materialized view concurrently with the refresh of that materialized view, and that materialized view includes joins and aggregation, Oracle Nov 6, 2015 · For this question's sake lets assume that the materialized view is with a two table join. REFRESH MATERIALIZED VIEW 完全更新具體化檢視表的內容。舊的內容將會被丟棄。如果指定了 WITH DATA（預設），則會執行檢視表上的查詢以産生新資料，並且使具體化檢視表處於可掃描查詢的狀態。如果指定了 WITH NO DATA，則不會産生新的資料，並且具體化檢視表將處於不可掃描查詢的狀態。 CONCURRENTLY 和 Sep 23, 2020 · 4 I created a materialized view in TimescaleDB (a PostgreSQL extension for time series data), and when I refresh it with the following code from PGAdmin, the latest data are added and all is well: REFRESH MATERIALIZED VIEW CONCURRENTLY public. I inserted few rows to one of the table and tried to refresh my_view by running query refresh materialized view my_ Jul 23, 2025 · When you refresh data for a materialized view, PostgreSQL locks the entire table therefore you cannot query data against it. Oct 2, 2019 · And refresh: refresh materialized view concurrently mv_secondary_id; As I understand from the documentation - concurrent queries on the view will be able to run on the view, but when I try to refresh and run a query - it waits for the refresh to end and only then completes. A Postgresql Materialized view with cardinality around 200k rows can be created with data in below minute, but cannot be refreshed. The command intends to run SQL functions as the owner of the materialized view, enabling safe refresh of untrusted materialized views. 描述 REFRESH MATERIALIZED VIEW 命令将完全替换物化视图的内容。要执行此命令，您必须对该物化视图拥有 MAINTAIN 权限。旧内容将被丢弃。如果指定了 WITH DATA （或默认），将执行底层查询来提供新数据，物化视图将处于可扫描状态。如果指定了 WITH NO DATA，则不生成新数据，物化视图将处于不可扫描状态 描述 REFRESH MATERIALIZED VIEW 完全替换一个 物化视图的内容。你必须是该物化视图的属主才能执行这个命令. Oct 9, 2014 · PostgreSQL 9. CONCURRENTLY Refresh the materialized view without locking out concurrent selects on the materialized view. Feb 17, 2025 · Materialized views that generate columns with non-unique values cannot use unique indexes - and cannot use the concurrent refresh option. time_series_mv WITH DATA; Mar 27, 2020 · This materialized view needs to update once every day (after midnight) as new data gets added/updated in those 5 tables. Sep 25, 2025 · Description CREATE MATERIALIZED VIEW defines a materialized view of a query. Currently the materialized views are a subset of the fields in the base tables, but as the database evolves we don't want the underlying tables to be locked into any specific form because of what the users may be doing. auto. This can be replicated with the following few lines of code: create materialized view tmp Mar 23, 2022 · Ideally I'd want the latest refresh to take precedence, but without failing the transaction already running in the other process (which would be the case if I simply kill the other process after checking for locks, as per Kill concurrent materialized view refresh PID ). Refresh the materialized view without locking out concurrent selects on the materialized view. I am having an issue when they happen in parallel i am getting some weird tuples updated concurrently errors. There seems to be an oversight with REFRESH MATERIALIZED VIEW (without CONCURRENTLY) as it's not listed there. I am using Postgres 11 on GCloud. Oct 26, 2025 · By the end of this tutorial, you’ll have a solid understanding of how to refresh materialized view concurrently and non- CONCURRENTLY, enabling you to make informed decisions and optimize your PostgreSQL database. CONCURRENTLY そのマテリアライズドビューに対して同時に実行されるSELECTをロックすることなく、マテリアライズドビューをREFRESHします。 このオプションを使わない場合、多くの行に影響を与えるREFRESHはリソースをあまり使わず、早く終わる代わりに、そのマテリアライズドビューから Sep 1, 2023 · In Oracle 23ai materialized view refreshes can be performed concurrently for on-commit fast refreshes by adding the ENABLE CONCURRENT REFRESH clause. I was afraid that this meant any attempt to make a simultaneous refresh would throw an error, but in the light of their answers, there isn't any special error involved. REFRESHing locks VIEW's read, and may subsequently make server and UI unresponsive. 4) While not an incremental update as you asked for, Postgres 9. 22. This Jul 7, 2016 · psql -c "refresh materialized view concurrently matviewX" & It runs right away and doesn't wait for the parents to finish refreshing because they don't lock their children from doing refreshes while they themselves are already refreshing concurrently. Jan 8, 2020 · ERROR: Cannot refresh materialized view "reporting. Feb 5, 2024 · Run REFRESH MATERIALIZED VIEW CONCURRENTLY in right security context The internal commands in REFRESH MATERIALIZED VIEW CONCURRENTLY are correctly executed in SECURITY_RESTRICTED_OPERATION mode, except for creating the temporary "diff" table, because you cannot create temporary tables in SRO mode. This will be addressed separately. The new data appears atomically as part of transaction commit. REFRESH MATERIALIZED VIEW CONCURRENTLY makes it non-read blocking; however Sending multiple repeated REFRESH's still blocks reading MUST be fixed with throttling Also, CONCURRENTLY needs UNIQUE INDEX on MATERIALIZED VIEW The solution??? - throttling Oct 30, 2024 · 1 Answer I faced a similar issue where REFRESH MATERIALIZED VIEW CONCURRENTLY failed with a permission denied error, but running it without CONCURRENTLY worked fine. mat_view" concurrently HINT: Create a uniqueindexwithnoWHERE clause on one or more columnsof the materialized view. Sep 25, 2025 · This option can only be used when the materialized view is already populated. For example if we had to denormalize a field that could break what materialized view consumers did. Losing access to the source data prevents updates, but doesn't immediately invalidate the existing materialized view from being read. Even with this option only one REFRESH at a time may run against any one materialized view. This is to ensure that when refreshing the vi Nov 1, 2015 · REFRESH MATERIALIZED VIEW CONCURRENTLY takes an EXCLUSIVE lock, so SELECT s may still run. I cannot seem to find this in the postgresql docs about how I would know when the refresh has completed in the background. In order to use this approach, a unique index must be added to the materialized view. 4, refreshing a materialized view meant locking the entire table, and therefore preventing anything querying it, and if a refresh took a long time to acquire the exclusive lock (while it waits for queries using Aug 3, 2023 · When you refresh data for a materialized view, PostgreSQL locks the entire table therefore you cannot query data against it. This guide also explores how Epsio’s incremental materialized views provide real-time updates with minimal overhead, enhancing performance and data consistency. Is there some other way to obtain the PID, Apr 4, 2015 · @MatheusOl a_horse_with_no_name is correct. Hint: Create a unique index with no WHERE clause on one or more columns of the materialized view Nov 22, 2024 · I have a materialize view that I update using REFRESH MATERIALIZED VIEW CONCURRENTLY my_view using a Kubernetes cronjob that runs every 15 minutes. Includes causes and solutions, along with step-by-step instructions. sql files specify WITH NO DATA If you include REFRESH MATERIALIZED VIEW <view name> as a separate migration (or even in the We would like to show you a description here but the site won’t allow us. 4 supports REFRESH MATERIALIZED VIEW CONCURRENTLY. I am looking to build a materialized view concurrently and once the view has been built. But creating the temporary "diff" table is a pretty complex CTAS command that selects from Jun 30, 2021 · 1 刷新物化视图以及 CONCURRENTLY 的介绍 对物化视图的刷新不阻塞在该物化视图上的并发选择。如果没有这个选项，一次影响很多行的刷新将使用更少的资源并且更快结束，但是可能会阻塞其他尝试从物化视图中读取的连接。这个选项在只有少量行被影响的情况下可能会更快。 只有当物化视图上有至少 描述 REFRESH MATERIALIZED VIEW 完全替换一个 物化视图的内容。你必须是该物化视图的属主才能执行这个命令. To view the service class configuration for WLM, use STV_WLM_SERVICE_CLASS_CONFIG. This prevents blocking of the entire view, but it does not speed up calculation time. This basically blocks any attempts to read a materialized Mar 17, 2014 · Starting from 9. Mar 29, 2021 · It needs to be REFRESH'd after update. Naturally, PostgreSQL also provides support for materialized views, and offers the end-user a powerful tool to handle more time-consuming requests. I've submitted a docs patch Nov 2, 2023 · I do not ask about tmp file settings, but why I can create the file with data in 53 seconds, but refreshing it takes longer for no real reason. 3 has introduced the first features related to materialized views. Nov 20, 2023 · cannot REFRESH MATERIALIZED VIEW "informationspermissions" because it is being used by active queries in this session I have tried making the refresh concurrent or not, the WITH DATA flag, to no avail. This temporary table is then swapped with the original materialized view once the refresh is complete. v_type" concurrently HINT: Create a unique index with no WHERE clause on one or more columns of the materialized view. We would like to show you a description here but the site won’t allow us. Here is the problem, when I refresh the materialized view without concurrent it is done in about 25-35 mins. Nov 16, 2017 · I'm trying to run REFRESH MATERIALIZED VIEW CONCURRENTLY recipe_search;, but PostgreSQL gives me this error: ERROR 55000 (object_not_in_prerequisite_state): cannot refresh materialized view "public. The reason for this requirement is that a concurrent refresh works different from a normal refresh: the query is executed, and the existing rows in the materialized view are updated or deleted or new rows inserted based on the query result. To avoid this, you can use the CONCURRENTLY option. The query is executed and used to populate the view at the time the command is issued (unless WITH NO DATA is used) and may be refreshed later using REFRESH MATERIALIZED VIEW. The entire materialized view is recalculated when using concurrently. When scheduling the refresh using cron. 4 does provide a new concurrent update feature. If you anticipate performing insert, update or delete operations on tables referenced by a materialized view concurrently with the refresh of that materialized view, and that materialized view includes joins and aggregation, Oracle PostgreSQL 刷新materialized views：并发性，事务行为 在本文中，我们将介绍如何在 PostgreSQL 中刷新 materialized views（物化视图），并讨论其并发性和事务行为。 阅读更多：PostgreSQL 教程 1. Jan 29, 2025 · REFRESH MATERIALIZED VIEW CONCURRENTLY mv_name; During a concurrent refresh, PostgreSQL creates a temporary table to hold the new results of the query. Jul 5, 2021 · When you refresh data for a materialized view, PostgreSQL locks the entire table therefore you cannot query data against it. Without this option, a refresh that updates a large number of rows will tend to use fewer resources and complete quicker. If you anticipate performing insert, update or delete operations on tables referenced by a materialized view concurrently with the refresh of that materialized view, and that materialized view includes joins and aggregation, Oracle Jul 26, 2018 · ERROR: cannot refresh materialized view “public. However, there are two preconditions that needs to be satisfied to do so: You must create an unique index on the materialized view The unique index must include all the records of the materialized view. Example: Create a materialized view manually using rails dbconsole using your WITH DATA option, Then dump with pg_dump --format=p --file=test. I would like to create an index on it concurrently the very first time and do a join with fresh data from the materialized view. Reviewed by Hitoshi Harada, Robert Haas, Andres Freund. Parameters CONCURRENTLY Refresh the materialized view without locking out concurrent selects on the materialized view. CONCURRENTLY AND WITH NO DATA cannot be used together. Mar 3, 2022 · Re: Cannot refresh materialized view concurrently if you have a column name called "mv" On Thu, Mar 3, 2022 at 02:53:47PM +0000, Rupert Agnew wrote: > Hi PSQL bugs, > > I have discovered a bug where a column name called “mv” in a materialized view > cannot be refreshed concurrently due to an internal PostgreSQL table alias also > named 描述 REFRESH MATERIALIZED VIEW 完全替换一个 物化视图的内容。旧的内容会被抛弃。如果指定了 WITH DATA （或者作为默认值），支持查询将被执行以 提供新的数据，并且会让物化视图将处于可扫描的状态。如果指定了 WITH NO DATA，则不会生成新数据并且会让物化视图 处于一种不可扫描的状态。 CONCURRENTLY 和 Oct 30, 2024 · postgres=# refresh materialized view concurrently mv_list_table ; ERROR: cannot refresh materialized view "public. So the materialized view is blocked for all concurrent access while it is being refreshed. mv_list_table" concurrently HINT: Create a uniqueindexwithnoWHERE clause on one or more columnsof the materialized view. 旧的内容会被抛弃。如果指定了 WITH DATA （或者作为默认值），支持查询将被执行以 提供新的数据，并且会让物化视图将处于可扫描的状态。如果指定了 WITH NO DATA，则不会生成新数据并且会让物化 CONCURRENTLY Refresh the materialized view without locking out concurrent selects on the materialized view. This We would like to show you a description here but the site won’t allow us. pg_dump, on the Aug 19, 2020 · If you drop orig read only table then while its getting recreated it wont be available. there is about 50k-150k updated rows that needs to be refreshed in mat view every day. About Refresh Modes for Materialized Views When creating a materialized view, you have the option of specifying whether the refresh occurs ON DEMAND or ON COMMIT. In other words you cannot have a WHERE clause in your create index command. May 14, 2021 · I get the following error: ERROR: must be owner of materialized view mv_sessions SQL state: 42501 When trying to refresh my materialized view: REFRESH MATERIALIZED VIEW CONCURRENTLY partners. Nov 29, 2021 · ERROR: cannot refresh materialized view "public. 刷新物化视图 物化视图的数据是预先计算和存储的，因此当原始表的数据发生变化时，物化视图也需要进行刷新以保持数据的一致性。在PostgreSQL中，可以使用 REFRESH MATERIALIZED VIEW 语句来刷新物化视图。默认情况下，刷新物化视图时会锁定它的依赖对象，这会导致其他查询阻塞。为了避免这种情况 刷新物化视图 物化视图的数据是预先计算和存储的，因此当原始表的数据发生变化时，物化视图也需要进行刷新以保持数据的一致性。在PostgreSQL中，可以使用 REFRESH MATERIALIZED VIEW 语句来刷新物化视图。默认情况下，刷新物化视图时会锁定它的依赖对象，这会导致其他查询阻塞。为了避免这种情况 To monitor REFRESH MATERIALIZED VIEW operations, use the following system views: To view any current updates on tables in the database, use STV_LOCKS. I'm experiencing a problem where it seems there are multiple refresh queries outstanding and waiting due to exclusive lock conflicts with each other. Jan 8, 2018 · Refresh the materialized view without locking out concurrent selects on the materialized view. To quote the doc… Prior to PostgreSQL 9. Then postgres will use the unique index on the materialized view to find which rows have changed and only update those rows from the recalculated values. Refreshing this view concurrently blocks all updates/inserts. Materialized views are an integral feature of pretty much all advanced database systems. The next scheduled refresh of the materialized view will fail. Mar 12, 2018 · Even with this option only one REFRESH at a time may run against any one materialized view. In that case, you’ll have to work around it with the regular refresh. However, materialized views in Postgres 9. Mar 16, 2024 · REFRESH MATERIALIZED VIEW CONCURRENTLY view_name; With the CONCURRENTLY option, PostgreSQL creates a temporary updated version of the materialized view, compares two versions, and performs INSERT and UPDATE only the differences. Merged after review with security patch Sep 9, 2025 · postgreSQL物化视图不会自动刷新数据，需要手动执行 REFRESH MATERIALIZED VIEW命令 REFRESH MATERIALIZED VIEW [ CONCURRENTLY ] name [ WITH [ NO ] DATA ]; Oct 26, 2025 · Yes, you can refresh materialized views concurrently with pg_cron by using the CONCURRENTLY option in the REFRESH MATERIALIZED VIEW command. This property can also be manipulated at runtime through both JMX and the setconcurrentviewbuilders and getconcurrentviewbuilders nodetool commands. Review questioned the Assert that a matview was not a system relation. This Jun 3, 2024 · I was asked to make materialized views for others to consume. mv_summary WITH DATA; CONCURRENTLY Refresh the materialized view without locking out concurrent selects on the materialized view. Both the scenarios are taken care when you use materialized view as it offers concurrent refresh feature as well. Dec 18, 2019 · Please note that "REFRESH MATERIALIZED VIEW CONCURRENTLY" has the same behaviour, but considerably slows the refresh (from a few minutes up to an hour), therefore aggravating the performance problem. I generally just refresh concurrently as most of the materialized views I use are for summary tables that take a very long time to update (10 minutes to an hour typically). sql <database_name>, and rails db:migrate and you'll note both your test. I'm not sure, but I think the REFRESH command is viewed as DDL by PostgreSQL, and PostgreSQL wraps all DDL within transactions so that simultaneous transactions can't see the effects of DDL commands issued by other concurrent transactions. This Refresh the materialized view without locking out concurrent selects on the materialized view. channel" concurrently. This Jan 7, 2025 · REFRESH MATERIALIZED VIEWのオプション 1 CONCURRENTLYオプションを使用すると、他のクエリをブロックせずに更新できます。 CONCURRENTLYオプションは、UNIQUEインデックスが必要です。 WITH NO DATAオプションは、データを生成せずにビューを更新します。 Dec 22, 2014 · Concurrent Update (Postgres 9. 刷新物化视图 物化视图是基于查询结果缓存的一种对象，它在查询时提供了更高的性能。但是，由于缓存的存在，物化 . REFRESH MATERIALIZED VIEW CONCURRENTLY data. However: They cannot REFRESH the materialized view. This May 27, 2024 · Step to reproduce the problem Create matview on source create materialized view metrics_count AS SELECT 1; Launch pgcopydb with follow pgcopydb clone --follow Recreate matview (drop/create) default Learn how to automatically refresh materialized views in PostgreSQL with this step-by-step guide. 5, Postgres supports Concurrent Refresh as stated here in the official documentation. In my testing I have a method called refresh_aggregrates that fundamentally calls REFRESH MATERIALIZED VIEW on my views. Control access to materialized views By default, materialized views are built in a single thread. This demonstrates how to use the CONCURRENTLY option with REFRESH MATERIALIZED VIEW. If you anticipate performing insert, update or delete operations on tables referenced by a materialized view concurrently with the refresh of that materialized view, and that materialized view includes joins and aggregation, Oracle Feb 8, 2024 · Late privilege drop in REFRESH MATERIALIZED VIEW CONCURRENTLY in PostgreSQL allows an object creator to execute arbitrary SQL functions as the command issuer. Aug 3, 2023 · Learn how to efficiently refresh PostgreSQL materialized views using manual, concurrent, and automated methods. e4ss qayy uhmc rtx wohsh b4wlk5 ail 9twfo5 e2gjqs epc