This release contains bug fixes since the 2.30.1 release. We recommend that you upgrade at the next available opportunity.

Bugfixes

• #10665 Fix crash when merging chunks with different column layouts
• #10668 Fix DROP SCHEMA CASCADE leaving orphaned compressed chunks
• #10682 Fix vectorized text comparison ignoring a non-deterministic collation given in the query
• #10609 Fix race while updating granular refresh setting for hypertable
• #10613 Rename the granular refresh options to timescaledb.cagg_granular_refresh_*
• #10636 Free the tenant tracker's shared memory when its hypertable is dropped
• #10585 Potential crash in CREATE TABLE AS query selecting from a compressed hypertable

This release contains bug fixes since the 2.30.0 release. We recommend that you upgrade at the next available opportunity.

Bugfixes

• #10580 Fix missing conflicts for INSERT ... ON CONFLICT with multiple unique constraints
• #10583 Fix NULL conflict resolution on single-column bloom filtering
• #10592 Fix duplicate rows from DeferredChunkAppend when LIMIT is not pushed down
• #10593 Fix cannot cast type cstring error in DeferredChunkAppend queries

Thanks

• @davidecentioni for reporting the problem with a LIMIT query on a hypertable returning duplicate rows once the plan goes generic #10584
• @vincentrolfs for reporting the problem of LIMIT query with enum columns and casting #10590

This release contains performance improvements and bug fixes since the 2.29.2 release. We recommend that you upgrade at the next available opportunity.

Highlighted features in TimescaleDB v2.30.0 Blazing fast LIMIT queries with the newly introduced DeferredChunkAppend. This custom node reduces planning significantly by delaying chunk expansion. During planning the hypertable stays unexpanded and only during execution are chunks enumerated on demand. Combined with the optimizations to FIRST and LAST sparse indexes, this addition executes last-point queries far more efficiently and quickly. This changes the scaling of the "What is the last reading from this sensor" query from linear with number of chunks to constant if it can be found in the most recent chunk. The true power of the custom node starts to show with increasing amount of chunks, see more elaborate benchmarks.

Features

• https://github.com/timescale/timescaledb/pull/10147 Support segmentwise batch sorted merge for overlapping batches
• https://github.com/timescale/timescaledb/pull/10292 Add DeferredChunkAppend custom scan
• https://github.com/timescale/timescaledb/pull/10354 Adds DML support for concurrent compaction
• https://github.com/timescale/timescaledb/pull/10388 Add custom toaster for compression

Bugfixes

• https://github.com/timescale/timescaledb/issues/10058 Apply new sortkeys for in-memory recompression
• https://github.com/timescale/timescaledb/pull/10128 Include hypertable chunks in publications created with FOR TABLES IN SCHEMA
• https://github.com/timescale/timescaledb/issues/10325 Avoid test errors when building from a source archive without a git repository
• https://github.com/timescale/timescaledb/pull/10408 Verify columns and their types in create_compressed_chunk
• https://github.com/timescale/timescaledb/pull/10515 Fix row level security checks after dropping hypertable columns
• https://github.com/timescale/timescaledb/issues/9905 Potentially incorrect result of a join when the join clause contains time_bucket
• https://github.com/timescale/timescaledb/issues/9920 Fix the "XX000: failed to evaluate runtime constant in vectorized filter" error in some queries that use stable functions in WHERE clause and the columnar aggregation pipeline
• https://github.com/timescale/timescaledb/pull/10499 Potentially wrong query result when hypertable chunks are filtered out at query run time, the filter condition uses an uncorrelated subquery, and the query uses a parallel execution plan
• https://github.com/timescale/timescaledb/pull/10513 Remove user_catalog_table option from catalog tables
• https://github.com/timescale/timescaledb/pull/10506 Correctly match NULL tuples to compressed batches with NULL boundaries during recompression
• https://github.com/timescale/timescaledb/pull/10524 Shared memory leak in the chunk stats subsystem when databases are dropped
• https://github.com/timescale/timescaledb/pull/10535 Fix chunk merging with default sparse indexes
• https://github.com/timescale/timescaledb/pull/10536 Skip batch size check when direct compress is set as hypertable option
• https://github.com/timescale/timescaledb/pull/10539 Allow deletes from the policy chunk stats table when the database publishes all tables

GUCs

• enable_deferred_chunk_append: Custom scan node for hypertables that iterates chunks at execution instead of expanding every chunk at plan time. Default: true.
• use_custom_toaster: Use a custom TOAST writer for compressed row inserts. Default: false.

Thanks

• @tureba for reporting the problem with building from a source archive without a git repository https://github.com/timescale/timescaledb/issues/10325
• @AlexFavre for reporting a failed extension update when a publication for all tables exists https://github.com/timescale/timescaledb/issues/10477
• @peterecofit for reporting potentially wrong query result when hypertable chunks are filtered out at query run time https://github.com/timescale/timescaledb/issues/10503
• @esdanieljaegers for reporting the issue and providing steps for reproduction https://github.com/timescale/timescaledb/issues/10511

This release contains bug fixes since the 2.29.1 release. We recommend that you upgrade at the next available opportunity.

Bugfixes

• #10189 Fix user-defined functions named time_bucket causing SQLSTATE XX000
• #10363 Fix time_bucket_gapfill() with window aggregates over constants
• #10416 Repair mismatched dimensional CHECK constraints
• #10423 Fix compressed SkipScan dropping uncompressed rows when sort keys do not match distinct keys
• #10430 Do not attach SkipScan to mismatched IndexScan paths under MergeAppend
• #9921 Fix wrong results for IS NULL predicates with min/max sparse-index pushdown

Thanks

• @borisborelly for reporting incorrect results with COUNT(DISTINCT) due to SkipScan dropping uncompressed rows.

This release contains performance improvements and bug fixes since the 2.29.0 release and fixes for security vulnerabilities (#10360, #10379, #10386). You can check the security advisory for more information on the vulnerability and the platforms that are affected. We recommend that you upgrade at the next available opportunity.

Bugfixes

• #10327 Assertion failure in add_dimension() when the hypertable argument is NULL
• #10339 Fix crash when deleting from a compressed continuous aggregate source
• #10340 Validate max_batches in compact_chunk()
• #10352 Reset inherited column and constraint flags on chunks during attach_chunk()
• #10360 Fix decompressor crashes with malformed compressed data
• #10369 Fix typo in error message about MERGE support on compressed hypertables
• #10379 Read hypertable max time value with an ordered scan
• #10386 Add missing permission checks to internal chunk functions

Thanks

• @JoongHyuk-Shin for reporting and fixing NULL handling in add_dimension()
• @igor2x for reporting a typo in a MERGE support error message
• @mdisec for reporting issues with compressed data validation during decompression

This release contains performance improvements and bug fixes since the 2.28.3 release. We recommend that you upgrade at the next available opportunity.

Release Highlights

• Chunk exclusion for DML operations drastically improves the performance of UPDATE and DELETE statements on hypertables. By acquiring exclusive locks only on the specific chunks being modified rather than the entire hypertable, this enhancement eliminates massive lock contention and keeps high-concurrency workloads running smoothly without unnecessary slowdowns.
• Intelligent row-by-row decompression enables the query planner to decompress data row-by-row rather than in large batches when an operation prioritizes a fast initial response (such as queries with LIMIT clauses). This dramatically reduces memory overhead and query latency, ensuring lightning-fast performance when you only need to retrieve a small subset of records from your compressed hypertables.

Important: PostgreSQL 15 Support Removed TimescaleDB 2.29.0 removes support for PostgreSQL 15. This release supports PostgreSQL 16, 17, and 18. If you are still running PostgreSQL 15, upgrade PostgreSQL before upgrading to TimescaleDB 2.29.0.

Backward-Incompatible Changes

• #10041 Remove support for PostgreSQL 15

Features

• #9315 Speed up DML operations on hypertables by using the optimized TimescaleDB hypertable expansion code instead of the generic PostgreSQL inheritance hierarchy expansion
• #9534 Speed up expression evaluation in the columnar pipeline by caching common subexpressions
• #9684 Add _timescaledb_functions.decompress_batch() SQL function
• #9732 Speed up some queries with small LIMIT by switching to row-by-row query execution pipeline
• #9917 Decompress less data in DML on compressed hypertables by accounting for prepared statement parameters
• #9957 Add compact_chunk() function
• #10048 Support concurrent refresh policies on hierarchical continuous aggregates
• #10081 Add samplerate argument to _timescaledb_functions.estimate_uncompressed_size()
• #10100 Skip classifying compressed relations to speed up planning
• #10118 Don't track compressed relations as separate chunk
• #10119 Reduce memory usage of INSERT queries using direct compress and spanning multiple chunks
• #10163 Add a compaction policy for unordered chunks
• #10204 Don't create separate hypertable catalog entry for hypertables with compression
• #10217 Initial placeholder version of granular refresh API
• #10225 Add config_merge parameter to alter_job() for merging jsonb into the existing job configuration
• #10226 Add recompress_unordered columnstore policy option
• #10231 Use regclass for storing relation reference in chunk table
• #10237 Add helper functions for decoding hypertable status
• #10240 Add the tsdb.direct_compress storage parameter that allows enabling direct compress for a given hypertable independent of global settings
• #10266 Add max_batches to compact_chunk()
• #10299 Add continuous_aggs_tenant_tracking and hypertable_cagg_settings catalogs

Bugfixes

• #10013 Make ownership error messages on continuous aggregates consistent
• #10052 Result of MIN / MAX aggregate functions in columnar aggregation pipeline possibly inconsistent with plain PostgreSQL result
• #10071 Prune the real-time branch of hierarchical continuous aggregates at any nesting depth
• #10143 Fix division by zero when planning time_bucket with zero width
• #10199 Fix initial_start handling in build_job_info
• #10213 Cache sort pathkeys per hypertable
• #10221 Fix incremental refresh skipping the last bucket
• #10278 Drop job_errors view in bgw_job_stat_history migration
• #10280 RETURNING clause returned no rows for INSERT using direct compress
• #10281 Disable direct compress when the destination table has an exclusion constraint so the constraint is still enforced
• #10282 Only count directly compressed rows toward the command tag when the INSERT sets it
• #10286 Propagate VACUUM on a chunk to the compressed relation when running on the chunk directly
• #10302 Fix useless-join removal and self-join elimination for hypertables
• #10313 Allow running ALTER EXTENSION timescaledb UPDATE inside a transaction block
• #10315 Fix overlap detection with running max
• #10324 Fix stale index entries after rebuild_sparse_index() on compressed chunks

GUCs

• timescaledb.enable_hypertable_expansion_for_dml: allow using the optimized TimescaleDB hypertable expansion code for UPDATE and DELETE instead of the generic PostgreSQL inheritance hierarchy expansion. On by default.

Thanks

• @FrancescEthon and @ManuelEthon for reporting an issue with incremental refresh skipping the last bucket
• @h0rn3t for reporting a problem with VACUUM not propagating to the compressed relation
• @igor2x for reporting an issue with locking during DML statements on hypertables
• @MaximeEthon for reporting an issue with prepared statement parameters in DML decompression
• @proddata for reporting a problem when upgrading from 2.15.3 to 2.28.2
• @tureba for reporting and fixing stale sparse-index entries after rebuild
• @viniciusrsouza for reporting an issue with hierarchical continuous aggregates

This release contains performance improvements and bug fixes since the 2.28.2 release. We recommend that you upgrade at the next available opportunity.

Bugfixes

• #10082 Wrong result when evaluating a function returning NULL in the columnar query execution pipeline
• #10178 Fix incorrect usage of sort transformation for sort key expressions with negative constants
• #10179 Allow enabling and disabling triggers on hypertables with columnstore enabled
• #10182 Fix columnstore sort pushdown to check for different query sort key collation
• #10209 Fix potentially wrong results for stddev(float4) and stddev(float8) when used with avg() in the columnar query execution pipeline
• #10212 Fix race condition when enabling compression on a hypertable
• #10230 Batch filtering for compressed DML should respect collation
• #10254 Direct delete failed to handle array predicates with NULL values and deleted more rows than intended (#10129)
• #10257 Reuse existing dimension_slice IDs when possible
• #10265 Truncate constraint name before trying to rename

Thanks

• @juantxorena for reporting that triggers could not be enabled or disabled on hypertables with columnstore enabled

This release contains bug fixes since the 2.28.1 release. We recommend that you upgrade at the next available opportunity.

Bugfixes

• #10126 Fix bgw_job_stat_history migration for 2.28.1
• #10133 Fix chunk_constraint migration
• #10137 Fix column ordering on first/last-based sparse indexes
• #10164 Automatically drop incompatible smallint bloom filters when upgrading instead of stopping the upgrade

Thanks

• @juantxorena for reporting an issue with update script for 2.28.1
• @rusha1333 for reporting an issue when upgrading to 2.28.1

This release contains performance improvements and bug fixes since the 2.28.0 release. We recommend that you upgrade at the next available opportunity.

Bugfixes

• #9913 Fix potential crash on DML on compressed tables when the plan uses Bitmap Heap Scan
• #10091 Fix column rename for compressed chunks
• #10056 Enforce CHECK, NOT NULL and view WITH CHECK OPTION constraints for direct compress inserts
• #10059 Fix error when using first/last aggregates in a HAVING clause
• #10060 Fix first/last optimization returning the same value for aggregates that share the value column but order by different columns
• #10061 Fix internal error in first/last for unsortable types
• #10069 Fix bgw_job_stat_history definition
• #10073 Fix uncompressed size estimate for varlen
• #10089 Fix deleting every row on compressed hypertable with subquery returning constant false
• #10094 Fix use-after-free in ALTER TABLE ADD CONSTRAINT

Thanks

• @skrenes for reporting a problem with the job_history view when upgrading to 2.28.0

This release contains performance improvements and bug fixes since the 2.27.2 release. We recommend that you upgrade at the next available opportunity.

Highlighted features in TimescaleDB v2.28.0

• Faster first() and last() queries on compressed data. TimescaleDB derives first(value, time) and last(value, time) aggregates straight from the columnstore's batch metadata, skipping batch decompression entirely. For the "latest reading per series" lookups that time-series workloads run constantly, that means meaningfully faster recency queries with no changes to your SQL queries.
• Lighter, less disruptive continuous aggregate refreshes. refresh_continuous_aggregate() can now run incrementally in batches — the same behavior refresh policies already use — enabling breaking large manual refreshes into smaller chunks (tunable via buckets_per_batch, max_batches_per_execution, and refresh_newest_first) instead of one heavy operation. Refreshes also now take a lighter lock while processing the invalidation log, so they no longer block unrelated concurrent operations on the same continuous aggregate, improving behavior for concurrent workloads.
• Vectorized execution now covers CASE expressions. TimescaleDB's columnar executor can now evaluate CASE ... WHEN expressions directly on compressed data, so queries using conditional logic stay on the fast vectorized path instead of falling back to slower row-by-row decompression. This speeds up a common pattern — conditional aggregations and computed columns over compressed history — with no query changes needed.
• Add new aggregations to a continuous aggregate without rebuilding it. You can now run ALTER MATERIALIZED VIEW <cagg> ADD COLUMN <name> <type> GENERATED ALWAYS AS (<aggregate>) STORED to add a new computed aggregate to an existing continuous aggregate in place — no more dropping and recreating the whole aggregate just to track one more metric. New data populates the column going forward, letting your rollups evolve alongside your application. (Existing rows start as NULL; a forced refresh backfills them when you need historical values.)

Deprecation Notice: PostgreSQL 15 Support This release marks the final minor version of TimescaleDB that will support PostgreSQL 15. Starting with our next release, version 2.29.0, we will officially drop support for Postgres 15, and only support Postgres 16, 17, and 18; however, all future patch releases within the current 2.28 version cycle will continue to fully support it. We recommend planning your PostgreSQL upgrades accordingly to ensure a smooth transition.

Deprecation Notice: chunk_constraint Catalog Table Please note that the _timescaledb_catalog.chunk_constraint table has been dropped and temporarily replaced by a view, which introduces a change to the underlying objects while maintaining current query behavior. However, this compatibility view will be completely removed in a future release. To ensure your queries remain compatible moving forward, we strongly advise transitioning to the stable contracts provided by our informational views.

Backward-Incompatible Changes

• #9934 Remove adaptive chunking

Features

• #4054 Support ANALYZE and VACUUM on continuous aggregates by redirecting to the underlying materialization hypertable
• #9125 Increase the parallelism of SELECT queries over compressed hypertables to approximately match the uncompressed data size
• #9410 Mark hypertable and chunk as user catalog tables
• #9416 Support some forms of CASE expression in columnar aggregation and grouping
• #9580 Add first / last sparse indexes to compression
• #9784 Use first / last sparse index for orderby metadata on new compressed chunks
• #9668 Allow database owner to configure hypertables and policies
• #9701 Relax lock during continuous aggregate invalidation log processing
• #9730 Add in-memory observability for compressed chunks
• #9735 Improve GapFill row count estimate
• #9821 Allow subquery results which are exec params as GapFill arguments
• #9825 Support ADD COLUMN on continuous aggregates
• #9842 Suppress continuous aggregate invalidation tracking during bulk loads
• #9878 Remove chunk_constraint catalog tracking for foreign keys
• #9893 Remove chunk_constraint catalog tracking for non-dimensional constraints
• #9903 Incremental refresh for refresh_continuous_aggregate()
• #9915 Remove _timescaledb_catalog.chunk_constraint table
• #9938 Add rebuild_sparse_index function
• #9964 Add a function to lock OSM chunk's dimension slice
• #9980 Support first/last(value, time) in ColumnarIndexScan

Bugfixes

• #9708 Guard time bucket parameter handling against bad input
• #9745 Check constraints when adding unique constraints to chunks
• #9890 Fix incremental refresh batch boundaries to align with variable-width buckets and start only where a chunk and an invalidation overlap
• #9914 Fix use-after-free in segmentwise recompression
• #9929 Fix background jobs being bumped in the queue forever and never running
• #9955 Fix wrong results when using Batch Sorted Merge with no first-last index on a non-leading order by column
• #9967 Block upgrade after downgrade with first/last indexes present
• #9976 Fix wrong results when comparing a date column to a timestamptz value
• #9977 Fix COPY WHERE into a hypertable with dropped columns
• #9981 Fix set-returning functions in the sort key of ColumnarScan
• #9982 Reject ALTER TABLE ... INHERIT when the parent is a hypertable
• #9984 Fix handling of NOT VALID NOT NULL constraint for query optimization
• #9986 Handle MERGE WHEN NOT MATCHED BY SOURCE on hypertables
• #9988 Fix time_bucket_gapfill function detection
• #10003 Block unsafe updates of unique columns on compressed chunks
• #10024 Fix approximate_row_count handling of Infinity
• #10025 Fix rename on compressed continuous aggregates
• #10026 Fix chunk skipping near PG_INT64_MAX

New Settings

• skip_cagg_invalidation: skip continuous aggregate invalidation tracking for DML and DDL in the current session/transaction. Off by default.
• stats_max_chunks: set the per-database compressed chunk statistics cache capacity. Defaults to 1024 chunks; set to 0 to disable the feature.

Thanks

• @Fabian-2596 for suggesting more accurate GapFill row count estimate
• @otjdiepluong for fixing spelling mistakes in timescaledb source code comments
• @scimad and @Nosfistis for suggesting expanding coverage for gapfill arguments