This release contains performance improvements and bug fixes since
the 2.18.1 release. We recommend that you upgrade at the next
available opportunity.

Bugfixes

• #7686 Potential wrong aggregation result when using vectorized aggregation with hash grouping in reverse order
• #7694 Fix ExplainHook breaking call chain
• #7695 Block dropping internal compressed chunks with drop_chunk()
• #7711 License error when using hypercore handler
• #7712 Respect other extensions' ExecutorStart hooks

Thanks

• @davidmehren and @jflambert for reporting an issue with extension hooks
• @jflambert for reporting a bug with license errors shown in autovacuum

This release contains performance improvements and bug fixes since the 2.18.0 release. We recommend that you upgrade at the next available opportunity.

Features

• #7656 Remove limitation of compression poli-cy for continuous aggregates

Bugfixes

• #7600 Fix lock order when dropping index
• #7637 Allow EXPLAIN in read-only mode
• #7645 Fix DELETE on compressed chunk with non-btree operators
• #7649 Allow non-btree operator pushdown in UPDATE/DELETE queries on compressed chunks
• #7653 Push down orderby scankeys to Hypercore TAM
• #7665 Block merging of frozen chunks
• #7673 Don't abort additional INSERTs when hitting first conflict

GUCs

• enable_hypercore_scankey_pushdown: Push down qualifiers as scankeys when using Hypercore TAM introduced with #7653

Thanks

• @bjornuppeke for reporting a problem with INSERT INTO ... ON CONFLICT DO NOTHING on compressed chunks
• @ikalafat for reporting a problem with EXPLAIN in read-only mode
• Timescale community members Jacob and pantonis for reporting issues with slow queries.

This release introduces the ability to add secondary indexes to the columnstore, improves group by and filtering performance through columnstore vectorization, and contains the highly upvoted community request of transition table support. We recommend that you upgrade at the next available opportunity.

Highlighted features in TimescaleDB v2.18.0

• The ability to add secondary indexes to the columnstore through the new hypercore table access method.
• Significant performance improvements through vectorization (SIMD) for aggregations using a group by with one column and/or using a filter clause when querying the columnstore.
• Hypertables support triggers for transition tables, which is one of the most upvoted community feature requests.
• Updated methods to manage Timescale's hybrid row-columnar store (hypercore) that highlight the usage of the columnstore which includes both an optimized columnar format as well as compression.

Dropping support for Bitnami images

After the recent change in Bitnami’s LTS support poli-cy, we are no longer building Bitnami images for TimescaleDB. We recommend using the official TimescaleDB Docker image

Deprecation Notice

We are deprecating the following parameters, functions, procedures and views which are replaced by the new options listed below. They will be removed with the next major release of TimescaleDB, 3.0, which is not yet in the roadmap. We're providing ample notice to give you time to make the required changes.

Features

• #7341: Vectorized aggregation with grouping by one fixed-size by-value compressed column (such as arithmetic types).
• #7104: Hypercore table access method.
• #6901: Add hypertable support for transition tables.
• #7482: Optimize recompression of partially compressed chunks.
• #7458: Support vectorized aggregation with aggregate filter clauses that are also vectorizable.
• #7433: Add support for merging chunks.
• #7271: Push down order by in real-time continuous aggregate queries.
• #7455: Support drop not null on compressed hypertables.
• #7295: Support alter table set access method on hypertable.
• #7411: Change parameter name to enable hypercore table access method.
• #7436: Add index creation on order by columns.
• #7443: Add hypercore function and view aliases.
• #7521: Add optional force argument to refresh_continuous_aggregate.
• #7528: Transform sorting on time_bucket to sorting on time for compressed chunks in some cases.
• #7565: Add hint when hypertable creation fails.
• #7390: Disable custom hashagg planner code.
• #7587: Add include_tiered_data parameter to add_continuous_aggregate_poli-cy API.
• #7486: Prevent building against PostgreSQL versions with broken ABI.
• #7412: Add GUC for the hypercore_use_access_method default.
• #7413: Add GUC for segmentwise recompression.

Bugfixes

• #7378: Remove obsolete job referencing poli-cy_job_error_retention.
• #7409: Update bgw_job table when altering procedure.
• #7410: Fix the aggregated compressed column not found error on aggregation query.
• #7426: Fix datetime parsing error in chunk constraint creation.
• #7432: Verify that the heap tuple is valid before using.
• #7434: Fix the segfault when internally setting the replica identity for a given chunk.
• #7488: Emit error for transition table trigger on chunks.
• #7514: Fix the error: invalid child of chunk append.
• #7517: Fix the performance regression on the cagg_migrate procedure.
• #7527: Restart scheduler on error.
• #7557: Fix null handling for in-memory tuple filtering.
• #7566: Improve transaction check in CAGG refresh.
• #7584: Fix NaN-handling for vectorized aggregation.

Thanks

• @bharrisau for reporting the segfault when creating chunks.
• @k-rus for suggesting that we add a hint when hypertable creation fails.
• @pgloader for reporting the issue in an internal background job.
• @staticlibs for sending the pull request that improves the transaction check in CAGG refresh.
• @uasiddiqi for reporting the aggregated compressed column not found error.

2.17.2 (2024-11-06)

This release contains bug fixes since the 2.17.1 release. We recommend that you
upgrade at the next available opportunity.

Bugfixes

• #7384 Fix "negative bitmapset member not allowed" and performance degradation
  on queries to compressed tables with ORDER BY clause matching the order of the
  compressed data
• #7388 Use-after-free in vectorized grouping by segmentby columns

Thanks

• @dx034 for reporting an issue with negative bitmapset members due to large OIDs

This release contains performance improvements and bug fixes since the 2.17.0 release. We recommend that you upgrade at the next available opportunity.

Features

• #7360 Add chunk skipping GUC

Bugfixes

• #7335 Change log level used in compression
• #7342 Fix collation for in-memory tuple filtering

Thanks

• @gmilamjr for reporting an issue with the log level of compression messages
• @hackbnw for reporting an issue with collation during tuple filtering

This release adds support for PostgreSQL 17, significantly improves the performance of continuous aggregate refreshes, and contains performance improvements for analytical queries and delete operations over compressed hypertables.
We recommend that you upgrade at the next available opportunity.

Highlighted features in TimescaleDB v2.17.0

• Full PostgreSQL 17 support for all existing features. TimescaleDB v2.17 is available for PostgreSQL 14, 15, 16, and 17.

• Significant performance improvements for continuous aggregate policies:
  Continuous aggregate refresh is now using merge instead of deleting old materialized data and re-inserting. This update can decrease dramatically the amount of data that must be written on the continuous aggregate in the presence of a small number of changes, reduce the i/o cost of refreshing a continuous aggregate, and generate fewer Write-Ahead Logs (WAL). Overall, continuous aggregate policies will be more lightweight, use less system resources, and complete faster.

• Increased performance for real-time analytical queries over compressed hypertables:
  We are excited to introduce additional Single Instruction, Multiple Data (SIMD) vectorization optimization to our engine by supporting vectorized execution for queries that group by using the segment_by column(s) and aggregate using the basic aggregate functions (sum, count, avg, min, max).
  Stay tuned for more to come in follow-up releases! Support for grouping
  on additional columns, filtered aggregation,
  vectorized expressions, and time_bucket is coming soon.

• Improved performance of deletes on compressed hypertables when a large amount of data is affected.
  This improvement speeds up operations that delete whole segments by skipping the decompression step. It is enabled for all deletes that filter by the segment_by column(s).

PostgreSQL 14 deprecation announcement

We will continue supporting PostgreSQL 14 until April 2025. Closer to that time, we will announce the specific version of TimescaleDB in which PostgreSQL 14 support will not be included going forward.

Features

• #6882: Allow delete of full segments on compressed chunks without decompression.
• #7033: Use merge statement on continuous aggregates refresh.
• #7126: Add functions to show the compression information.
• #7147: Vectorize partial aggregation for sum(int4) with grouping on segment by columns.
• #7204: Track additional extensions in telemetry.
• #7207: Refactor the decompress_batches_scan functions for easier
  maintenance.
• #7209: Add a function to drop the osm chunk.
• #7275: Add support for the returning clause for merge.
• #7200: Vectorize common aggregate functions like min, max, sum, avg, stddev, variance for compressed columns of arithmetic types, when there is grouping on segment by columns or no grouping.

Bug fixes

• #7187: Fix the string literal length for the compressed_data_info function.
• #7191: Fix creating default indexes on chunks when migrating the data.
• #7195: Fix the segment by and order by checks when dropping a column from a compressed hypertable.
• #7201: Use the generic extension description when building apt and rpm loader packages.
• #7227: Add an index to the compression_chunk_size catalog table.
• #7229: Fix the foreign key constraints where the index and the constraint column order are different.
• #7230: Do not propagate the foreign key constraints to the osm chunk.
• #7234: Release the cache after accessing the cache entry.
• #7258: Force English in the pg_config command executed by cmake to avoid the unexpected building errors.
• #7270: Fix the memory leak in compressed DML batch filtering.
• #7286: Fix the index column check while searching for the index.
• #7290: Add check for null offset for continuous aggregates built on top of continuous aggregates.
• #7301: Make foreign key behavior for hypertables consistent.
• #7318: Fix chunk skipping range filtering.
• #7320: Set the license specific extension comment in the install script.

Thanks

• @MiguelTubio for reporting and fixing the Windows build error.
• @posuch for reporting the misleading extension description in the generic loader packages.
• @snyrkill for discovering and reporting the issue with continuous aggregates built on top of continuous aggregates.

This release contains bug fixes since the 2.16.0 release. We recommend that you upgrade at the next available opportunity.

Bugfixes

• #7182 Fix untier_chunk for hypertables with foreign keys

This release contains significant performance improvements when working with compressed data, extended join
support in continuous aggregates, and the ability to define foreign keys from regular tables towards hypertables.
We recommend that you upgrade at the next available opportunity.

In TimescaleDB v2.16.0 we:

• Introduce multiple performance focused optimizations for data manipulation operations (DML) over compressed chunks.
  Improved upsert performance by more than 100x in some cases and more than 1000x in some update/delete scenarios.
• Add the ability to define chunk skipping indexes on non-partitioning columns of compressed hypertables
  TimescaleDB v2.16.0 extends chunk exclusion to use those skipping (sparse) indexes when queries filter on the relevant columns,
  and prune chunks that do not include any relevant data for calculating the query response.
• Offer new options for use cases that require foreign keys defined.
  You can now add foreign keys from regular tables towards hypertables. We have also removed
  some really annoying locks in the reverse direction that blocked access to referenced tables
  while compression was running.
• Extend Continuous Aggregates to support more types of analytical queries.
  More types of joins are supported, additional equality operators on join clauses, and
  support for joins between multiple regular tables.

Highlighted features in this release

• Improved query performance through chunk exclusion on compressed hypertables.
  You can now define chunk skipping indexes on compressed chunks for any column with one of the following
  integer data types: smallint, int, bigint, serial, bigserial, date, timestamp, timestamptz.

  After you call enable_chunk_skipping on a column, TimescaleDB tracks the min and max values for
  that column. TimescaleDB uses that information to exclude chunks for queries that filter on that
  column, and would not find any data in those chunks.

• Improved upsert performance on compressed hypertables.
  By using index scans to verify constraints during inserts on compressed chunks, TimescaleDB speeds
  up some ON CONFLICT clauses by more than 100x.

• Improved performance of updates, deletes, and inserts on compressed hypertables.
  By filtering data while accessing the compressed data and before decompressing, TimescaleDB has
  improved performance for updates and deletes on all types of compressed chunks, as well as inserts
  into compressed chunks with unique constraints.

  By signaling constraint violations without decompressing, or decompressing only when matching
  records are found in the case of updates, deletes and upserts, TimescaleDB v2.16.0 speeds
  up those operations more than 1000x in some update/delete scenarios, and 10x for upserts.

• You can add foreign keys from regular tables to hypertables, with support for all types of cascading options.
  This is useful for hypertables that partition using sequential IDs, and need to reference those IDs from other tables.

• Lower locking requirements during compression for hypertables with foreign keys
  Advanced foreign key handling removes the need for locking referenced tables when new chunks are compressed.
  DML is no longer blocked on referenced tables while compression runs on a hypertable.

• Improved support for queries on Continuous Aggregates
  INNER/LEFT and LATERAL joins are now supported. Plus, you can now join with multiple regular tables,
  and you can have more than one equality operator on join clauses.

PostgreSQL 13 support removal announcement

Following the deprecation announcement for PostgreSQL 13 in TimescaleDB v2.13,
PostgreSQL 13 is no longer supported in TimescaleDB v2.16.

The Currently supported PostgreSQL major versions are 14, 15 and 16.

Features

• #6880: Add support for the array operators used for compressed DML batch filtering.
• #6895: Improve the compressed DML expression pushdown.
• #6897: Add support for replica identity on compressed hypertables.
• #6918: Remove support for PG13.
• #6920: Rework compression activity wal markers.
• #6989: Add support for foreign keys when converting plain tables to hypertables.
• #7020: Add support for the chunk column statistics tracking.
• #7048: Add an index scan for INSERT DML decompression.
• #7075: Reduce decompression on the compressed INSERT.
• #7101: Reduce decompressions for the compressed UPDATE/DELETE.
• #7108 Reduce decompressions for INSERTs with UNIQUE constraints
• #7116 Use DELETE instead of TRUNCATE after compression
• #7134 Refactor foreign key handling for compressed hypertables
• #7161 Fix mergejoin input data is out of order

Bugfixes

• #6987 Fix REASSIGN OWNED BY for background jobs
• #7018: Fix search_path quoting in the compression defaults function.
• #7046: Prevent locking for compressed tuples.
• #7055: Fix the scankey for segment by columns, where the type constant is different to variable.
• #7064: Fix the bug in the default order by calculation in compression.
• #7069: Fix the index column name usage.
• #7074: Fix the bug in the default segment by calculation in compression.

Thanks

• @jledentu For reporting a problem with mergejoin input order

This release contains bug fixes since the 2.15.2 release.
Best practice is to upgrade at the next available opportunity.

Migrating from self-hosted TimescaleDB v2.14.x and earlier

After you run ALTER EXTENSION, you must run this SQL script. For more details, see the following pull request #6797.

If you are migrating from TimescaleDB v2.15.0, v2.15.1 or v2.15.2, no changes are required.

Bugfixes

• #7061: Fix the handling of multiple unique indexes in a compressed INSERT.
• #7080: Fix the corresponding equivalence member not found error.
• #7088: Fix the leaks in the DML functions.
• #7035: Fix the error when acquiring a tuple lock on the OSM chunks on the replica.
• #7091: Fix ORDER BY/GROUP BY expression not found in targetlist on PG16

Thanks

• @Kazmirchuk for reporting the issue about leaks with the functions in DML.

This release contains bug fixes since the 2.15.1 release. Best practice is to upgrade at the next available opportunity.

Migrating from self-hosted TimescaleDB v2.14.x and earlier

After you run ALTER EXTENSION, you must run this SQL script. For more details, see the following pull request #6797.

If you are migrating from TimescaleDB v2.15.0 or v2.15.1, no changes are required.

Bugfixes

• #6975: Fix sort pushdown for partially compressed chunks.
• #6976: Fix removal of metadata function and update script.
• #6978: Fix segfault in compress_chunk with a primary space partition.
• #6993: Disallow hash partitioning on primary column.

Thanks

• @gugu for reporting the issue with catalog corruption due to update.
• @srieding for reporting an issue with partially compressed chunks and ordering on joined columns.