2022 feature updates for PolarDB for PostgreSQL-PolarDB(PolarDB)-阿里云帮助中心

V1.1.29

Ganos (V5.1)

Category	Feature	Description	References	Release date
New feature	ST_GeoHashID function	Converts GeoHash strings to integer values.	ST_GeoHashID	December 2022
	ST_GeoHashFromID function	Converts integer values to GeoHash strings.	ST_GeoHashFromID	December 2022
	ST_UpdatePyramid function	Enables updates to vector pyramids.	ST_UpdatePyramid	December 2022
	ST_SetUpdatePyramidRules function	Lets you configure rules for vector pyramid updates.	ST_SetUpdatePyramidRules	December 2022
	ST_BuildPyramidUseGeomSideLen function	Builds a vector pyramid based on the size of the vector bounding box.	ST_BuildPyramidUseGeomSideLen	December 2022
	ST_InterpolateRaster function	Performs spatial interpolation.	ST_InterpolateRaster	December 2022
	ST_Contour function	Generates contours.	ST_Contour	December 2022
	ST_Statistics function	Performs statistical analysis on raster data with custom weights using MultiPoint.	ST_Statistics	December 2022
	ST_Resample function	Performs trajectory resampling.	ST_Resample	December 2022
	ST_Density function	Calculates trajectory density statistics.	ST_Density	December 2022
	ST_StayPoint function	Identifies stay points in trajectories.	ST_StayPoint	December 2022
Bug fixes	Fixed an issue where st_buildhistogram emptied the raster object.			December 2022
	Fixed an issue with ST_AsTable where passing a null value caused a crash and an incorrect z-value.			December 2022
	Fixed incorrect results from ST_Split when splitting data by GeoHash.			December 2022
	Fixed incorrect attribute field encoding in ST_Tile.			December 2022

V1.1.28

Minor engine version

Category	Parameter	Description	References	Release date
New feature	Default value changes for some parameters	Starting with minor engine versions V1.1.28 (PostgreSQL 11) and V14.5.1.1 (PostgreSQL 14), uses new default values for some parameters. These changes apply only to new clusters and significantly improve database performance. You can modify these parameters in the console.	Default value changes for some parameters	November 2022
	smlar plug-in	The smlar plug-in efficiently calculates data similarity.	smlar (approximate vector)	November 2022
	hypopg plug-in	The hypopg plug-in evaluates if a hypothetical index improves query performance.	hypopg (hypothetical index)	November 2022
	pg_bigm plug-in	The pg_bigm plug-in provides full-text search and uses a 2-gram GIN index to accelerate searches.	pg_bigm (fuzzy search)	November 2022
	hll plug-in	The hll plug-in supports the HyperLogLog (hll) data type for quickly estimating business metrics like page views (PV) and unique visitors (UV).	hll (approximate set)	November 2022
	varbitx plug-in	extends the varbit plug-in with additional BIT operations for broader application support.	varbitx	November 2022
	ZomboDB plug-in	ZomboDB is a PostgreSQL extension that supports native access methods and provides powerful text indexing and analysis for PostgreSQL databases.	ZomboDB	November 2022
Fixed issue	Fixed an issue that allowed a user with `UPDATE` permission but without `SELECT` permission on certain columns of a partitioned table to infer denied column values from error messages. For more information, see CVE-2021-3393.			November 2022

V1.1.27

Minor engine version

Category	Parameter	Description	References	Release date
New Feature	Real-time materialized views	PolarDB now supports real-time materialized views. These views stay consistent with their base tables during Data Manipulation Language (DML) operations, significantly improving query performance.	Real-time materialized views	October 2022
	pg_sphere plug-in	The pg_sphere plug-in, a PostgreSQL extension, adds spherical data types, functions, and operators.	pg_sphere (Spherical data calculation)	October 2022
	Failover slot support	The logical replication slot failover feature in and synchronizes all logical replication slots from the primary instance to a secondary instance to ensure replication continuity after a failover.	Logical replication slot failover	October 2022
	Tuple-granularity PX scanning	Adds the `polar_px_scan_granularity` parameter to control the scanning granularity for parallel execution (PX). Valid values: `set polar_px_scan_granularity = row;`: PX scans at tuple granularity. `set polar_px_scan_granularity = block;`: (Default) PX scans at block granularity. Note Block-level scanning provides higher performance for large data scans.	N/A	October 2022
	polar_enable_strategy_reject_buffer parameter	Adds the `polar_enable_strategy_reject_buffer` parameter to control whether the ring buffer limit can be bypassed in batch read scenarios. Valid values: `off` (Default): Uses the ring buffer for batch reads. If a buffer retrieved from the ring contains a dirty page, the backend process flushes the page to disk. `on`: Allows batch reads to bypass the ring buffer limit. If a buffer retrieved from the ring contains a dirty page, a new buffer is obtained from the buffer pool. This reduces the number of flushes performed by the backend process and can improve query speed. However, since the ring buffer limit is bypassed, data from the current query may fill the buffer pool, which can cause buffer eviction and subsequent I/O operations when multiple connections query different tables.	N/A	October 2022

V1.1.26

minor engine version

Category

Feature

Description

References

Release date

New feature

Logon and logoff triggers

Logon and logoff triggers are event triggers that invoke a specified function or stored procedure when a user logs on or logs off.

Logon and logoff triggers

September 2022

Batch writes to cache

Adds thepolar_enable_strat_bulkwrite parameter to control how much cache space data written by a session can occupy. The default value istrue. Valid values:

true: Behaves identically to native PostgreSQL. Data written by each session can only occupy a portion of the cache space.
false: Allows data written by a session to use the entire cache space.

Note

In most cases, you can use the default value true. This ensures that each session has a dedicated portion of cache space and does not evict cached data from other sessions.
We recommend setting this parameter to false when you want to cache all data from batch write operations. This improves the cache hit ratio for subsequent reads and reduces disk I/O.
For best results, use this parameter in conjunction with thepolar_enable_strat_scan parameter. Setting both parameters to false allows data to be written to and read from the entire cache space.
```
set polar_enable_strat_bulkwrite = false; -- Allows writing to the entire cache space.
set polar_enable_strat_scan = false; -- Allows reading from or loading to the entire cache space.
```

N/A

September 2022

Ganos (V4.9)

Category	Feature	Description	References	Release date
New feature	ST_Intersection aggregate function	Aggregates an array of geometry objects.	ST_Intersection	September 2022
	ST_AddZ function	Accepts an array of Z-coordinates as a parameter and converts a 2D or 3DM geometry object to a 3D or 4D geometry object.	ST_AddZ	September 2022
	ST_SetValue function	Sets pixel values at specified pixel positions or within the spatial range of a specified geometry object.	ST_SetValue	September 2022
Enhancement	ST_ExportTo function	The ST_ExportTo function can now export a raster object to a COG file.	ST_ExportTo	September 2022
	ST_CreateRast function	The ST_CreateRast function can now convert multiple records or an array of regular grid points into a raster object.	ST_CreateRast	September 2022
	ST_Split function	The ST_Split function can now split trajectories by a specified start time or by trajectory point index.	ST_Split	September 2022
	ST_Union function	The ST_Union function can now execute in batches based on memory usage, which prevents out-of-memory (OOM) errors when processing large datasets.	ST_Union	September 2022
	ST_CreateRast function	The ST_CreateRast function can now create a raster object from raster data stored in HDFS.	ST_CreateRast	September 2022
	ST_ImportFrom function	The ST_ImportFrom function can now import raster data from HDFS.	ST_ImportFrom	September 2022
	ST_ExportTo function	The ST_ExportTo function can now export raster data to an HDFS file system.	ST_ExportTo	September 2022
Fixed issues	Fixed an issue where the ST_makeTrajectory function could cause the database to crash.			September 2022
	Fixed an issue where the ST_lcsSimilarity function could not identify time intervals measured in days.			September 2022
	Fixed an issue where the ST_AsEWKB function could not convert trajectories built from data tables.			September 2022
	Fixed excessive memory consumption in the ST_BuildPyramid function when building a vector pyramid from a large dataset.			September 2022

V1.1.25

Minor engine version

Category	Feature	Description	References	Release date
New	pgAudit plugin	Adds support for the pgAudit plugin to generate audit logs.	pgAudit	August 2022

V1.1.24

Minor engine version

Category

Parameter

Description

References

Release date

New feature

plan_cache_mode

Adds the plan_cache_mode parameter to configure the plan cache mode. The default value is auto. Valid values:

auto: Automatically selects between the custom and generic modes.
force_custom_plan: Forces the use of the custom plan generated by the optimizer.
force_generic_plan: Forces the use of the generic plan from the plan cache.

N/A

July 2022

Ganos (V4.7)

Category	Parameter	Description	References	Release date
New feature	ST_makeTrajectory function	Lets you convert table rows into a trajectory.	ST_makeTrajectory	July 2022
New feature	ST_AsTable function	Lets you convert a trajectory into a table.	ST_AsTable	July 2022
Fixed issue	Fixed an issue where anonymous temporary tables were not automatically deleted during raster data operations.			July 2022

V1.1.23

Minor engine version

Category	Parameter	Description	References	Release date
New feature	pg_hint_plan	Adds support for the `pg_hint_plan` plugin, which lets you adjust a SQL statement's execution plan by adding hints in special comments.	pg_hint_plan	June 2022
New feature	Optimizes the resource manager's memory release process	Adds the `mem_release_policy` parameter to control the memory release policy. Default: `default`. Valid values: `default`: When the memory usage limit is exceeded, the resource manager uses an adaptive policy that prioritizes releasing memory from idle processes over active processes. `cancel_query`: Cancels queries only for active processes. `terminate_idle_backend`: Terminates idle user processes. `terminate_any_backend`: Terminates any user process. `none`: Performs no action. Adds the `total_memcontext_dump_rate` parameter to set the output threshold for `memory context` information. Default: 75. Range: 20 to 95. The change takes effect after a restart or reload. Adds the `max_proc_mcxtdump_num` parameter to set the maximum number of processes for which to output `memory context` information. Default: 1. Range: 1 to 100. The change takes effect after a restart or reload. Adds the `interval_max_num` parameter to set the output interval for `memory context` information. Default: 0. Range: 0 to INT32_MAX. The change takes effect after a restart or reload.	N/A	June 2022

V1.1.22

minor engine version

Category	Parameter	Description	References	Release date
New feature	PX Analyze	Introduces the `polar_px_enable_explain_all_stat` parameter. In parallel query scenarios, when used with the `explain analyze` command, it displays the execution details for each worker, including the number of tuples processed and the time taken. Introduces the `polar_px_explain_memory_verbosity` parameter. In parallel query scenarios, when used with the `explain analyze` command, it displays the memory usage of each worker. Valid values: `summary`: Displays a summary of the memory usage for all workers. `detail`: Displays the detailed memory usage for each worker.	N/A	March 2022
New feature	Support for Clang compilation	Now supports Clang compilation.	N/A	March 2022

Ganos (V4.6)

Category	Parameter	Description	References	Release date
New feature	Object storage paths	Enables access to raster data from self-managed MinIO servers.	Object storage service paths	March 2022
New feature	ST_PointValues	Introduces the `ST_PointValues` raster function, which returns the pixel values for all bands.	ST_PointValues	March 2022
Fixed issue	Fixed an issue where the ST_Clip function returned an incorrect band order for raster data.			March 2022
	Fixed a performance issue caused by a missing primary key index during raster data updates.			March 2022
	Fixed an issue that prevented reads of trajectory data from OSS from retrying on failure.			March 2022

Ganos (V4.5)

Category	Parameter	Description	References	Release date
New feature	Ganos now supports the PostgreSQL 14 series.		N/A	March 2022
Optimized feature	Enhanced the caching mechanism for trajectory objects in external storage to improve access performance.		N/A	March 2022
Fixed issue	Fixed an issue where file suffixes were missing when exporting raster data to OSS.			March 2022
Fixed issue	Fixed an issue that caused statistics collection to fail for some raster data.			March 2022

V1.1.20

Minor engine version

Category	Parameter	Description	References	Release date
New features	Drop flashback for tables	Adds the drop flashback feature, which lets you quickly restore deleted tables, and view and clear the recycle bin.	Drop flashback	January 2022
	Parallel query for multi-level partitioned tables	Now supports parallel queries on multi-level partitioned tables.	Use cross-node parallel query for partitioned tables	January 2022
	Support for GBK/GB18030 encoding	now supports the GBK and GB18030 server encoding formats.	Specify the server encoding format	January 2022

Ganos (V4.4)

Category	Parameter	Description	References	Release date
New features	ST_LinearStretch function	Adds the ST_LinearStretch function, which applies a linear stretch to a raster and returns a new raster.	ST_LinearStretch	January 2022
	ST_BuildPercentiles function	Adds the ST_BuildPercentiles function, which calculates pixel value percentiles for a raster.	ST_BuildPercentiles	January 2022
	ST_ComputeStatistics function	Adds the ST_ComputeStatistics function, which calculates the statistics, histogram, and percentiles for raster data in a single operation.	ST_ComputeStatistics	January 2022
	ST_Percentile function	Adds the ST_Percentile function, which retrieves the pixel percentiles for a raster.	ST_Percentile	January 2022
Enhancements	Parallel computing	Enhanced the ST_SummaryStats and ST_BuildHistogram functions to support parallel computing.	N/A	January 2022
	ST_ExportTo function	Enhanced the ST_ExportTo function to return false instead of an error when the destination file already exists.	N/A	January 2022
	ST_ImportFrom function	Enhanced the ST_ImportFrom function to return detailed error information during data import, which simplifies troubleshooting.	ST_ImportFrom	January 2022
Fixed issues	Fixed an issue where rounding during a raster crop operation could cause a half-pixel loss.			January 2022
Fixed issues	Fixed an issue that caused an error when importing or calculating statistics for raster data containing values such as `NAN` and `INF`.			January 2022