This release contains performance improvements and bug fixes since the 2.21.3 release. We recommend that you upgrade at the next available opportunity.
Highlighted features in TimescaleDB v2.22.0
- Sparse indexes on compressed hypertables can now be explicitly configured via
ALTER TABLE
rather than relying only on internal heuristics. Users can define indexes on multiple columns to improve query performance for their specific workloads. - [Tech Preview] Continuous aggregates now support the
timescaledb.invalidate_using
option, enabling invalidations to be collected either via triggers on the hypertable or directly from WAL using logical decoding. Aggregates inherit the hypertable’s method if none is specified. - UUIDv7 compression and vectorization are now supported. The compression algorithm leverages the timestamp portion for delta-delta compression while storing the random portion separately. The vectorized equality/inequality filters with bulk decompression deliver ~2× faster query performance. The feature is disabled by default (
timescaledb.enable_uuid_compression
) to simplify the downgrading experience, and will be enabled out of the box in the next minor release. - Hypertables can now be partitioned by UUIDv7 columns, leveraging their embedded timestamps for time-based chunking. We’ve also added utility functions to simplify working with UUIDv7, such as generating values or extracting timestamps - e.g.,
uuid_timestamp()
returns a PostgreSQL timestamp from a UUIDv7. - SkipScan now supports multi-column indexes in not-null mode, improving performance for distinct and ordered queries across multiple keys.
Removal of the hypercore table access method
We made the decision to deprecate the hypercore table access method (TAM) with the 2.21.0 release. Hypercore TAM was an experiment and it did not show the performance improvements we hoped for. It is removed with this release. Upgrades to 2.22.0 and higher are blocked if TAM is still in use. Since TAM’s inception in 2.18.0, we learned that btrees were not the right architecture. Recent advancements in the columnstore, such as more performant backfilling, SkipScan, adding check constraints, and faster point queries, put the columnstore close to or on par with TAM without needing to store an additional index. We apologize for the inconvenience this action potentially causes and are here to assist you during the migration process.
Migration path
do $$
declare
relid regclass;
begin
for relid in
select cl.oid from pg_class cl
join pg_am am on (am.oid = cl.relam)
where am.amname = 'hypercore'
loop
raise notice 'converting % to heap', relid::regclass;
execute format('alter table %s set access method heap', relid);
end loop;
end
$$;
Features
- #8247 Add configurable alter settings for sparse indexes
- #8306 Add option for invalidation collection using WAL for continuous aggregates
- #8340 Improve selectivity estimates for sparse minmax indexes, so that an index scan on a table in the columnstore is chosen more often when it's beneficial.
- #8360 Continuous aggregate multi-hypertable invalidation processing
- #8364 Remove hypercore table access method
- #8371 Show available timescaledb
ALTER
options when encountering unsupported options - #8376 Change
DecompressChunk
custom node name toColumnarScan
- #8385 UUID v7 functions for testing pre PG18
- #8393 Add specialized compression for UUIDs. Best suited for UUID v7, but still works with other UUID versions. This is experimental at the moment and backward compatibility is not guaranteed.
- #8398 Set default compression settings at compress time
- #8401 Support
ALTER TABLE RESET
for compression settings - #8414 Vectorised filtering of UUID Eq and Ne filters, plus bulk decompression of UUIDs
- #8424 Block downgrade when orderby setting is
NULL
- #8454 Remove internal unused index helper functions
- #8494 Improve job stat history retention policy
- #8496 Fix dropping chunks with foreign keys
- #8505 Add support for partitioning on UUIDv7
- #8513 Support multikey SkipScan when all keys are guaranteed to be non-null
- #8514 Concurrent continuous aggregates improvements
- #8528 Add the
_timescaledb_functions.chunk_status_text
helper function - #8529 Optimize direct compress status handling
Bugfixes
- #8422 Don't require
columnstore=false
when using the TimescaleDB Apache 2 Edition - #8493 Change log level of
not null
constraint message - #8500 Fix uniqueness check with generated columns and hypercore
- #8545 Fix error in LOCF/Interpolate with out-of-order and repeated columns
- #8558 Error out on bad args when processing invalidation
- #8559 Fix
timestamp out of range
usingend_offset=NULL
on CAgg refresh policy
GUCs
enable_multikey_skipscan
: Enable SkipScan for multiple distinct keys, default: onenable_uuid_compression
: Enable UUID compression functionality, default: offcagg_processing_wal_batch_size
: Batch size when processing WAL entries, default: 10000cagg_processing_low_work_mem
: Low working memory limit for continuous aggregate invalidation processing, default: 38.4MBcagg_processing_high_work_mem
: High working memory limit for continuous aggregate invalidation processing, default: 51.2MB
Thanks
- @CodeTherapist for reporting an issue where foreign key checks did not work after several insert statements
- @moodgorning for reporting a bug in queries with LOCF/Interpolate using out-of-order columns
- @nofalx for reporting an error when using
end_offset=NULL
on CAgg refresh policy - @pierreforstmann for fixing a bug that happened when dropping chunks with foreign keys
- @Zaczero for reporting a bug with CREATE TABLE WITH when using the TimescaleDB Apache 2 Edition