ClickHouse roadmap 2026

This is the ClickHouse roadmap 2026.

This roadmap does not cover the tasks related to infrastructure, orchestration, documentation, marketing, external integrations, drivers, etc.

See also:

Roadmap 2025: https://github.com/ClickHouse/ClickHouse/issues/74046
Roadmap 2024: https://github.com/ClickHouse/ClickHouse/issues/58392
Roadmap 2023: https://github.com/ClickHouse/ClickHouse/issues/44767
Roadmap 2022: https://github.com/ClickHouse/ClickHouse/issues/32513
Roadmap 2021: https://github.com/ClickHouse/ClickHouse/issues/17623
Roadmap 2020: [link](https://github.com/ClickHouse/ClickHouse/blob/be29057de1835f6f4a17e03a422b45b81efe6833/docs/ru/whats-new/extended-roadmap.md)
Roadmap 2019: [link](https://presentations.clickhouse.com/2018-roadmap/)
Roadmap 2018: [link](https://presentations.clickhouse.com/2017-meetup11/news_and_plans/)

## Query Engine

- [ ] Parallel replicas for Merge tables #67770
- [x] Materialized CTE #94849
- [ ] Optimization by combining aggregation with topK
- [x] Optimization of aggregation with flat combining #79428
- [ ] Cache for deserialized columns
- [x] Cascades cost-based optimizer for JOINs
- [ ] Using partition key to optimize JOINs
- [ ] Using partition key to optimize DISTINCT, IN, GROUP BY, and LIMIT BY
- [x] Runtime filters for JOINs by default
- [ ] Optimization of anti-joins: LEFT JOIN ... WHERE ... IS NULL to NOT IN
- [x] Deriving index condition from the right-hand side of INNER JOIN
- [x] Support for certain SQL functions without parentheses #52102
- [ ] Optimizations for a single dictionary in LowCardinality #72717
- [ ] Block-level hints (= algebraic properties of intermediate chunks: sortedness, uniqueness, clustering of identical values) #48800
- [x] Query cache for subqueries #51656
- [ ] Query cache for partial results #57490
- [ ] On-disk query cache #52141
- [x] Improvements for the query condition cache
- [ ] Streaming queries #63312
- [x] Enable JIT compilation on macOS #100947
- [ ] Query plan caching #93812

## Resiliency

- [ ] Automatic external memory for DISTINCT and LIMIT BY
- [ ] Automatic external memory for IN
- [x] Automatic external memory for JOIN https://github.com/ClickHouse/ClickHouse/pull/97813
- [x] Memory configuration in the workload scheduler #82414
- [ ] GROUP BY in order by default
- [x] Automatic selection of max_insert_threads
- [x] Tracking the space in external memory
- [ ] Spill to S3 in addition to spill to the cache
- [x] Allow the cancellation of scalar subqueries #100230

## Data Storage

- [x] Text index in GA
- [ ] Unique key constraint #70589
- [ ] Automatic LowCardinality columns #69916
- [x] Compact statistics storage
- [x] Statistics by default https://github.com/ClickHouse/ClickHouse/pull/101275
- [ ] Virtual shards on top of shared storage ☁
- [x] Automatic buckets in Map data type [#99200](https://github.com/ClickHouse/ClickHouse/pull/99200)
- [ ] Transactions for Replicated tables
- [ ] Scoring in the text index

## Data Lakes

- [x] Metadata caching for Parquet files
- [ ] Support arbitrary nesting in database and table names #71171
- [ ] Support for case-insensitive database, table, and column names #33935
- [ ] Support for deletion vectors in Iceberg v3
- [x] Query Condition Cache for data lakes
- [x] Lazy columns reading for data lakes
- [ ] Data Lake catalogs in GA
- [x] Automatic cluster functions for subqueries
- [x] Support for AWS S3 Tables
- [x] Support for Google BigLake
- [x] Plain Rewritable metadata storage to support hard links
- [ ] Materialized views on top of data lakes
- [ ] Background merges for data lakes ☁

## Interfaces

- [x] Allow interactive queries to finish in the background #49683
- [ ] Configurable query rewrite rules #80084
- [ ] PromQL dialect in GA
- [x] Support for Arrow Flight SQL
- [ ] Kafka2 in GA
- [x] Configuration of query handlers with SQL
- [ ] Remote and Cloud database engines #59304
- [x] Drivers for UDFs #71172
- [x] WebAssembly UDFs
- [x] API for query construction #64336
- [ ] Even simpler data upload #38775
- [ ] Passing input data to the url table function #45994
- [x] Framing formats for query results
- [ ] Predictive autocomplete in the CLI #69641

## Cleanups

- [ ] Remove old analyzer
- [ ] Remove old predicate pushdown mechanics
- [x] Remove the hypotheses index
- [x] Remove Parquet reader v1
- [x] Remove or fix Kusto (KQL)
- [x] Remove Window View in favor of streaming queries