Expanding customer notifications for ClickHouse Managed Postgres. Oct 26, 2026 · 6 minutes read In August, ClickHouse, Inc. introduced customer notifications for ClickHouse Managed Postgres, starting with a warning when storage usage passes 85%. ClickHouse, Inc. wanted to give you a heads-up when something needs attention, without asking you to keep a dashboard open. Storage warning rendered from a received internal test email. This example reported 96% usage. These storage alerts are already helping customers take action. As an example, customers got in touch after receiving an alert, and ClickHouse, Inc. helped bring their disk usage back down. A customer confirms that the storage alert brought the issue to their attention. Customer details obscured. Conversations like these have helped ClickHouse, Inc. see where ClickHouse, Inc. can be more proactive. ClickHouse, Inc. is adding more specific notifications so you have a clearer idea of what's happening and what to check next. For this customer, an unused replication slot was retaining about 650 GB of transaction logs, something the upcoming inactive-slot notification will help identify. Here's what to expect next. ClickHouse, Inc. is adding five notifications covering inactive replication slots, planned switchovers, unplanned failovers, long-running transactions, and connection usage. Inactive replication slots. Applications often stream changes from Postgres to downstream systems using CDC tools like Debezium. These pipelines use logical replication slots to track which changes their consumers still need. A slot remains in Postgres even when its consumer disconnects. As your application writes more data, Postgres can retain write-ahead log (WAL) data for that consumer. A paused pipeline or an abandoned replication setup can leave storage usage growing while the application appears to be working normally. The upcoming notification will identify slots observed to be inactive with at least 10 GiB of unconfirmed WAL over a two-hour observation period. It will include the slot names so you know what to investigate. Slots identified as belonging to its managed CDC service will be excluded. One common use case is streaming from Managed Postgres to ClickHouse for analytics through ClickPipes which uses logical replication slots. For this setup, you can also switch to WalShadow, which uses physical WAL replication and eliminates the need for logical replication slots, avoiding this source of WAL buildup. Illustration: an inactive slot can retain WAL as new writes arrive. The upcoming notification will identify the slot. Planned switchover. A planned switchover promotes a standby to become the primary for your Postgres service. For example, scaling up CPU, memory, or storage brings up a replacement instance that catches up before taking over as primary. Automatic storage scaling uses the same process. Existing connections are interrupted during the switch. The upcoming notification will tell you that the switchover has completed and identify the affected service. Your connection string stays the same. If you're investigating a brief interruption, the notification will show when the primary changed. Planned-switchover email from an internal test received October 21, 2026, edited to remove an outdated parenthetical. Unplanned failover. If a primary becomes unavailable, a service with a standby can recover by promoting that standby to primary. The upcoming unplanned failover notification will tell you when that promotion has completed. The notification will identify the affected service and explain that the primary became unavailable. Your application can reconnect using the same connection string. Unplanned-failover email rendered from an internal test received October 22, 2026. Together, these two notifications will make it easier to tell whether an interruption came from a planned switchover or recovery after an unexpected failure. Its high availability documentation covers the recovery process in more detail. Long-running transactions. Sometimes a transaction stays open long after you expect its work to have finished. It might still be running a query, or it might be sitting idle while the application waits before committing or rolling back. Depending on what it has done, an open transaction can hold locks, block other work, or prevent vacuum from reclaiming dead rows. That can lead to table bloat and slower queries. The upcoming notification will warn when ClickHouse, Inc. observe a transaction on your primary that has been open for at least two hours. It will cover both active transactions and those idle in a transaction, and report the transaction's age when it was checked. You can then check whether the transaction is expected or was unintentionally left open. Connections approaching their limit. As you add application instances or increase worker concurrency, connection usage can climb faster than you expect. A connection pool is usually configured per application instance, so scaling out the application can multiply the total number of database connections. Once the available connections are exhausted, new application connections can fail. An upcoming notification will warn when usage reaches 95% of the limit so you can investigate before that happens. Start by checking which applications hold the connections and whether those sessions are active or idle. Then review your pool settings and look for connections that the application has stopped using but hasn't closed or returned to the pool. What's next. ClickHouse, Inc. want Managed Postgres to tell you when something needs attention and give you enough context to act. ClickHouse, Inc.'ll keep expanding notifications based on the problems ClickHouse, Inc. see customers encounter. You can manage delivery for the notifications currently available to your service (including the console, email, and Slack) in the Postgres section of your notification settings. See the notification documentation for details. Is there something else you'd like a heads-up about? Let ClickHouse, Inc. know at [email protected]. Get started with ClickHouse Managed Postgres today. Interested in seeing how ClickHouse Managed Postgres works on your data? Get started with ClickHouse Cloud in minutes and receive $300 in free credits.

ClickHouse - funding & investors. Last updated: October 16, 2026 ClickHouse's funding rounds. ClickHouse has raised a total of $1.05B over 7 funding rounds: 3 Early-Stage, 3 Late-Stage and 1 Debt round s. ClickHouse's largest funding round so far was a Series D round for $400M in Jan 2026. Here is the list of all funding rounds of ClickHouse: ClickHouse's investors. ClickHouse has total 36 investor s, 33 are institutional investors including Index Ventures and 32 others, 3 are Angel investors including Christian McCaffrey and 2 others. Here is the list of institutional investors of ClickHouse: * Dragoneer Investment Group, located in San Francisco (United States), made their first investment in ClickHouse on Jan 16, 2026 in its Series D round. * Bessemer Venture Partners, located in Redwood City (United States), made their first investment in ClickHouse on May 29, 2025 in its Series C round. * GIC, located in Singapore (Singapore), made their first investment in ClickHouse on May 29, 2025 in its Series C round. * Index Ventures, located in London (United Kingdom), made their first investment in ClickHouse on Aug 2021 in its Series A round. * Khosla Ventures, located in Menlo Park (United States), made their first investment in ClickHouse on May 29, 2025 in its Series C round. * Lightspeed Venture Partners, located in Menlo Park (United States), made their first investment in ClickHouse on Oct 28, 2021 in its Series B round. * T. Rowe Price, located in Baltimore (United States), made their first investment in ClickHouse on Jan 16, 2026 in its Series D round. * WCM Investment Management, located in Laguna Beach (United States), made their first investment in ClickHouse on Jan 16, 2026 in its Series D round. * Citi Ventures Studio, located in New York (United States), made their first investment in ClickHouse on Oct 07, 2025 in its Series C round. * Insight Partners, located in New York City (United States), made their first investment in ClickHouse on Oct 07, 2025 in its Series C round. * Peak XV Partners, located in Bengaluru (India), made their first investment in ClickHouse on Oct 07, 2025 in its Series C round. * Founders Circle Capital, located in Campbell (United States), made their first investment in ClickHouse on Oct 07, 2025 in its Series C round. * Adams Street Partners, located in Beijing (China), made their first investment in ClickHouse on Oct 07, 2025 in its Series C round. * Rosberg Ventures, located in Monte Carlo (Monaco), made their first investment in ClickHouse on Oct 07, 2025 in its Series C round. * Expanding Capital, located in Burlingame (United States), made their first investment in ClickHouse on Oct 07, 2025 in its Series C round. * Altimeter Capital, located in Boston (United States), made their first investment in ClickHouse on Oct 28, 2021 in its Series B round. * IVP, located in Menlo Park (United States), made their first investment in ClickHouse on May 29, 2025 in its Series C round. * Bond Capital, located in San Francisco (United States), made their first investment in ClickHouse on May 29, 2025 in its Series C round. * D. E. SHAW INDIA, located in Hyderabad (India), made their first investment in ClickHouse on Oct 07, 2025 in its Series C round. * Stifel, located in St. Louis (United States), made their first investment in ClickHouse on May 29, 2025 in its Conventional Debt round. * Goldman Sachs, located in New York City (United States), made their first investment in ClickHouse on May 29, 2025 in its Conventional Debt round. * Battery Ventures, located in Boston (United States), made their first investment in ClickHouse on May 29, 2025 in its Series C round. * Benchmark, located in San Francisco (United States), made their first investment in ClickHouse on Aug 2021 in its Series A round. * Coatue, located in New York City (United States), made their first investment in ClickHouse on Oct 28, 2021 in its Series B round. * FirstMark, located in New York City (United States), made their first investment in ClickHouse on Oct 28, 2021 in its Series B round. * Nebius, located in Amsterdam (Netherlands), made their first investment in ClickHouse on May 29, 2025 in its Series C round. * Thrive Capital, located in New York City (United States), made their first investment in ClickHouse on Dec 16, 2022 in its Series B round. * Yandex, located in Moscow (Russia), made their first investment in ClickHouse on Aug 2021 in its Series A round. * Redpoint Ventures, located in Woodside (United States), made their first investment in ClickHouse on Oct 28, 2021 in its Series B round. * Almaz Capital, located in Portola Valley (United States), made their first investment in ClickHouse on Oct 28, 2021 in its Series B round. * Lead Edge Capital, located in New York City (United States), made their first investment in ClickHouse on Oct 28, 2021 in its Series B round. Are you a Founder? FAQs about ClickHouse's funding and investors. Explore latest companies that raised funding recently * Factrika - raised a funding of $930K in Seed round held on Sep 17, 2026. * Eight Knot - raised a funding of $2.9M in Series A round held on Sep 17, 2026. * Magentic - raised a funding of $18M in Series A round held on Sep 17, 2026. * MicroLub - raised a funding of $10M in Series A round held on Sep 17, 2026. * hellohaven.ai - raised a funding of $15M in Seed round held on Sep 17, 2026.

ClickHouse 26.9 adds incremental refreshable materialized views, time-limited CREATE TOKEN credentials and boundary-based LIMIT. ClickHouse 26.9 ships 56 new features, adding APPEND INCREMENTAL refreshable views for Iceberg, CREATE TOKEN credentials, LIMIT AFTER/UNTIL, and DISTINCT disk spilling. Verified pipeline | Sources: 2 | Publisher: signed | Contributor: signed | Hash: d9f74eac9d | View Overview. ClickHouse has released version 26.9. According to the ClickHouse release post, the release "contains 56 new features | 135 performance optimizations | and 464 bug fixes." The 26.9 release call slides list the same three counts. The previous spring release was covered in ClickHouse 26.5. What The Machine Herald know. Incremental refreshable materialized views. The release post says ClickHouse 26.9 adds APPEND INCREMENTAL to refreshable materialized views, so that instead of scanning the entire source table on every refresh, ClickHouse processes only the rows committed since the previous refresh. The post says this can be used to copy append-only data into another ClickHouse table or to replicate an event stream from a MergeTree table into an Iceberg data lake. Per the same post, block-number and block-offset columns provide the cursor ClickHouse uses to identify rows committed after the previous refresh. For an Iceberg target, the post says ClickHouse stores the incremental cursor in the snapshot summary, and that if ClickHouse restarts, the next refresh resumes from that position instead of replaying the same events. The post credits Smita Kulkarni as the contributor. CREATE TOKEN. According to the release post, CREATE TOKEN lets a user create a time-limited credential for applications, scripts, CI jobs, and agents without exposing or replacing their main password. The post states that a token never grants more privileges than the user already has and stops working when it expires or if the user is removed. If no VALID UNTIL or VALID FOR is given, the default lifetime is 30 minutes, and ClickHouse displays the token only once. The slides show the syntax CREATE TOKEN VALID FOR INTERVAL 7 DAY GRANTS (SELECT ON default.sales);. The post credits Alexey Milovidov. LIMIT with boundary conditions. The release post says 26.9 extends LIMIT with boundary conditions that start and stop output based on values in the ordered result stream, "a capability that, to our knowledge, is not currently available in any other database." That is ClickHouse's own claim and was not independently verified. AFTER includes the row that matches its condition, UNTIL stops before its matching row, and ALL applies the boundary each time the condition matches. One example in the post, LIMIT 5 AFTER status >= 500, starts at the first server-error response in a log table and returns five requests. The post credits Zakhar Kravchuk and Nihal Miaji. Performance and other changes. * Min, max and count from statistics: the post says ClickHouse stores minimum and maximum values for numeric-like columns in each data part, and as of 26.9 can use those statistics to answer min, max, and count queries without reading the underlying column data. The use_statistics_for_min_max_aggregation setting disables the optimization. * DISTINCT spilling: setting max_bytes_before_external_distinct lets DISTINCT spill its intermediate state to disk. The post says ClickHouse automatically enables external DISTINCT when max_bytes_ratio_before_external_distinct is set to 0.5, meaning spilling starts when it reaches half of the memory available. * JSON and time types: the post says 26.9 adds bracket syntax for accessing paths in a JSON value, and allows Time values as offsets when adding to or subtracting from DateTime values. * PromQL: the post says 26.9 expands PromQL support with more functions, additional Prometheus HTTP API endpoints, and direct SELECT queries against TimeSeries tables. PromQL and the TimeSeries table engine are in private preview on ClickHouse Cloud. What The Machine Herald don't know. * Both cited sources are published by ClickHouse itself; no independent benchmarks or third-party evaluation of the new features were found. * The sources reviewed do not state how the incremental refresh mode behaves for update- or delete-heavy source tables, since the described use case is append-only data. * No source reviewed gives performance figures for the min/max/count statistics optimization or the DISTINCT spilling path.