Release notes for TimescaleDB v2.15.0 (#3186)

Signed-off-by: Fabrízio de Royes Mello <fabriziomello@gmail.com>
Co-authored-by: Iain Cox <iain@timescale.com>

about/release-notes/index.md

@@ -17,6 +17,79 @@ GitHub and be notified by email whenever a new release is available. On the
 click `Watch`, select `Custom` and then check `Releases`.
 </Highlight>
 
+## TimescaleDB&nbsp;2.15.0 on 2024-05-08
+
+<Highlight type="note">
+This release contains the performance improvements and bug fixes introduced since
+TimescaleDB v2.14.2. Best practice is to upgrade at the next available opportunity.
+</Highlight>
+
+#### Highlighted features in this release
+
+* [Continuous Aggregate](/api/:currentVersion:/continuous-aggregates/create_materialized_view/#sample-usage) now supports `time_bucket` with `origin` and/or `offset`.
+* The following improvements have been introduced for [hypertable compression](/api/:currentVersion:/compression/):
+  - Added planner support to check more kinds of WHERE conditions before decompression. 
+    This reduces the number of rows that have to be decompressed.
+  - You can now use `minmax` sparse indexes when you compress columns with `btree` indexes.
+  - Make compression uses the defaults functions.
+  - Vectorize filters in the WHERE clause contain text equality operators and LIKE expressions.
+
+#### Deprecation warning
+
+* You can no longer create continuous aggregates using `time_bucket_ng`.
+  This feature will be completely removed in the next release. Best practice is to 
+  [migrate your current continuous aggregates to the new form](/use-timescale/:currentVersion:/continuous-aggregates/migrate/), 
+* This is the last release supporting PostgreSQL 13.
+
+#### For self-hosted TimescaleDB v2.15.0 deployments only
+
+After you run `ALTER EXTENSION`, you must run [this SQL script](https://github.com/timescale/timescaledb-extras/blob/master/utils/2.15.X-fix_hypertable_foreign_keys.sql). For more details, see the 
+following pull requests [#6786](#6797).
+
+### Complete list of features
+* #6382 Support for `time_bucket` with origin and offset in CAggs.
+* #6696 Improve the defaults for compression `segment_by` and `order_by`.
+* #6705 Add sparse minmax indexes for compressed columns that have uncompressed btree indexes.
+* #6754 Allow `DROP CONSTRAINT` on compressed hypertables.
+* #6767 Add metadata table `_timestaledb_internal.bgw_job_stat_history` for tracking job execution history.
+* #6798 Prevent usage of the deprecated `time_bucket_ng` in the CAgg definition.
+* #6810 Add telemetry for access methods.
+* #6811 Remove the no longer relevant `timescaledb.allow_install_without_preload` GUC.
+* #6837 Add migration path for CAggs using `time_bucket_ng`.
+* #6865 Update the watermark when truncating a CAgg.
+
+### Complete list of bugfixes
+* #6617 Fix error in show_chunks.
+* #6621 Remove metadata when dropping chunks.
+* #6677 Fix snapshot usage in CAgg invalidation scanner.
+* #6698 Define meaning of 0 retries for jobs as no retries.
+* #6717 Fix handling of compressed tables with primary or unique index in COPY path.
+* #6726 Fix constify cagg_watermark using window function when querying a CAgg.
+* #6729 Fix NULL start value handling in CAgg refresh.
+* #6732 Fix CAgg migration with custom timezone / date format settings.
+* #6752 Remove custom autovacuum setting from compressed chunks.
+* #6770 Fix plantime chunk exclusion for OSM chunk.
+* #6789 Fix deletes with subqueries and compression.
+* #6796 Fix a crash involving a view on a hypertable.
+* #6797 Fix foreign key constraint handling on compressed hypertables.
+* #6816 Fix handling of chunks with no constraints.
+* #6820 Fix a crash when the ts_hypertable_insert_blocker was called directly.
+* #6849 Use non-orderby compressed metadata in compressed DML.
+* #6867 Clean up compression settings when deleting compressed CAgg.
+* #6869 Fix compressed DML with constraints of form value OP column.
+* #6870 Fix bool expression pushdown for queries on compressed chunks.
+
+### Acknowledgments
+* @brasic for reporting a crash when `ts_hypertable_insert_blocker` was called directly.
+* @bvanelli for reporting an issue with the jobs retry count.
+* @djzurawsk for reporting an error about dropping chunks.
+* @Dzuzepppe for reporting the issue that DELETEs using a subquery on compressed chunks was working incorrectly.
+* @hongquan for reporting a 'timestamp out of range' error during CAgg migrations.
+* @kevcenteno for reporting that the `show_chunks` API returned an incorrect output when 'created_before/created_after' 
+  was used with time-partitioned columns.
+* @mahipv for starting working on the job history PR.
+* @rovo89 for reporting that constify `cagg_watermark` was not working using the window function when querying a CAgg.
+
 ## TimescaleDB&nbsp;2.14.2 on 2024-02-20
 
 <Highlight type="note">
@@ -693,4 +766,4 @@ For release notes for older TimescaleDB versions, see the
 [migrate-caggs]: /use-timescale/:currentVersion:/continuous-aggregates/migrate/
 [join-caggs]: /use-timescale/:currentVersion:/continuous-aggregates/create-a-continuous-aggregate/#create-a-continuous-aggregate-with-a-join
 [multi-node-to-timescale-service]:/migrate/:currentVersion:/playbooks/multi-node-to-timescale-service/
-[multi-node-deprecation]: https://github.com/timescale/timescaledb/blob/main/docs/MultiNodeDeprecation.md
+[multi-node-deprecation]: https://github.com/timescale/timescaledb/blob/main/docs/MultiNodeDeprecation.md