This topic describes the feature updates to the minor versions of the kernel, console, Ganos, and API of PolarDB-O.

Note You can execute the following statement to view the minor version of the kernel of PolarDB-O:
show polar_version;

March 2021

Minor version of the kernel (V1.1.10)

Category Feature Description References
New Partitioned table BEFORE row-level triggers can be used in partitioned tables. BEFORE row-level trigger
polar_outline plug-in The polar_outline plug-in can be used to adjust execution plans. This optimizes SQL statements. The document is being updated.
Optimization Partitioned table Subpartition templates can be used for interval range partitioning. Subpartition templates
Performance optimization The read performance of data files is optimized by caching information about table sizes in shared memory. None
Compatibility The INTERVAL and FLOAT8 data types support the following operators:
  • +
  • -
  • *
  • /
None
Compatibility The OPT_PARAM hint is added. You can use this hint to specify the values of specific parameters in a single SQL statement. The document is being updated.

Ganos (V3.5)

Category Feature Description References
New Storage optimization for large spatio-temporal objects The Simple storage policy is added to optimize storage for large spatio-temporal objects. Use the Simple storage policy
Optimization Raster object When you use a raster object to update another raster object that has chunked data, the system automatically deletes the chunked data in the original raster object. None
Fixed issues The following issue is fixed: The Ganos Trajectory extension fails to be upgraded.
The following issue is fixed: An error occurs when a raster object is resampled by using the average resampling method in some cases.
The following issue is fixed: Query results may be invalid if the trajectory points for multiple timestamps are the same in a trajectory object.
The issue that the conversion operation is terminated after a GEOS object fails to be converted is fixed. In addition, the system prompts the causes of the conversion failure.

Minor version of the kernel (V1.1.9)

Category Feature Description References
New Partitioned table Interval range partitioning is supported. Interval range partitioning is an extension to range partitioning. Interval range partitioning allows a database to automatically create a partition when data to be inserted exceeds the range of an existing partition. Interval range partitioning
Range partitioning and interval range partitioning can be switched. Switch between range partitioning and interval range partitioning
Subpartition templates are supported. You can use subpartition templates to define subpartitions and simplify the specification of subpartitions. You need only to define subpartition descriptors in a subpartition template and then apply the subpartition template to each partition in a table. This way, you can define the subpartition descriptors for multiple partitions in the table at a time. Subpartition templates
AWR for performance monitoring Automatic Workload Repository (AWR) collects and analyzes performance statistics. You can use AWR to generate a statistical analysis report of a specific period based on statistics, such as dynamic views of a database, and analyze the database performance within the specific period. None
Optimization Partitioned table Partition pruning is enabled in the execution plan for a partitioned table. This improves query performance. None
Data type PolarDB-O uses TIMESTAMP as the DATE data type. A TIMESTAMP value is accurate to microseconds. In Oracle, a DATE value is accurate to seconds. To ensure compatibility between PolarDB-O and Oracle, the system automatically converts a DATE value into a TIMESTAMP(0) value. None
WAL The pipeline technology is used to reduce the proportion of write-ahead logging (WAL) overhead. This improves overall system performance. None
TO_CHAR TO_CHAR(text1, text2) automatically identifies the data type of text1 and text2. If text1 and text2 are valid DATE values, the function automatically converts text1 into a TIMESTAMP value. None
Fixed issues Useless SIGHUP signals are deleted.
The following issue is fixed: The system may stop responding when you execute the MERGE INTO statement for a partitioned table.
The following issue is fixed: An illegal memory access error occurs when you use pg_icu_collate_names.
The following issue is fixed: An illegal memory access error occurs when you execute the ALTER QUEUE ADD CALL statement.
The following issue is fixed: An illegal memory access error occurs when you enter a string of a variable length in the rdname field of a POLICY system table. This error is returned because the data type of the rdname field is set to a fixed-length data type.
The following issue is fixed: The return values of functions are truncated because the functions are not declared in the transparent data encryption (TDE) feature.
The following issue is fixed: The roaringbitmap plug-in encounters an illegal memory access error when exception parameters are entered.
The following issue is fixed: If the sync latency is high when logs are synchronized from a primary node to read-only nodes, the read-only nodes may not immediately give feedback on streaming replication to the primary node. As a result, the streaming replication is interrupted.

Ganos (V3.4)

Category Feature Description References
New Storage optimization for large spatio-temporal objects The feature signatures of large spatio-temporal objects are used. This accelerates the process of creating indexes on spatio-temporal data, makes spatial queries more efficient, and optimizes the storage modes of spatio-temporal objects. In addition, the polar_enable_storage_partial parameter is added. You can specify this parameter to enable the metadata of spatio-temporal objects to be stored in-row and the entity data of spatio-temporal objects to be stored off-row. Feature signature-based storage optimization for large spatio-temporal objects
Parallel execution of functions supported by the raster module The ST_ImportFrom function can be used to import raster data in parallel. ST_ImportFrom
The ST_BuildPyramid function can be used to create pyramids in parallel based on raster data. ST_BuildPyramid
Trajectory Empty The Trajectory Empty object is added. This allows null objects to be returned if requirements are not met in some scenarios. None
Fixed issues The following issue is fixed: The ST_AddZ function may return an invalid result if the input parameter is a 16-bit signed integer (16BSI).
The following issue is fixed: The trajectory module fails to be upgraded in some scenarios.
The following issue is fixed: Some functions cannot use indexes in the trajectory module.
The following issue is fixed: An error instead of the value false is returned because some nd functions fail to resolve the problem that time periods in two scenarios are not intersected.

January 2021

Minor version of the kernel (V1.1.8)

Category Feature Description References
New DBMS_STATS plug-in The DBMS_STATS plug-in is supported. You can use this plug-in to collect the related statistics when the database is running, back up statistics, and restore statistics from backups. DBMS_STATS
Transaction splitting after a write request Transaction splitting is supported for transactions that contain statements for read requests sent after a write request at the READ COMMITTED isolation level. All read requests that are generated from the start time to the end time of a transaction can be sent to read-only nodes. This ensures read/write consistency in the transaction. Transaction splitting
Optimization OR operator In earlier versions, an expression that contains the OR operator cannot be converted into an expression that contains the UNION ALL operator. This makes queries inefficient because full table scans are performed. In the latest version, an expression that contains the OR operator is automatically converted into an expression that contains the UNION ALL operator. This optimizes the logic and improves query performance. None
Compatibility with ECPG
  • ECPGPlus is compatible with partial syntax of Pro*C.
  • ECPGPlus is compatible with the connection method of native Oracle.
None
Compatibility with Oracle The GROUP BY CONST/EMPTY clause is compatible with the Oracle syntax. None
PBP By default, the persisted buffer pool for the primary node is enabled. None
Synchronization of partitioned tables to Kafka The process of synchronizing the configurations of partitioned tables from PolarDB-O to Kafka is optimized. Data is synchronized to Kafka based on parent tables. After data is synchronized, parent tables that use the same names as the source tables are created on Kafka. None
Users The following syntax is adjusted: CREATE USER ... IDENTIFIED BY ...This syntax is used to create only standard users. Create a user
Fixed issues The following issue is fixed: Tasks fail to be deleted when logical replication is used to synchronize the DBMS_JOB tables that do not have primary keys.
The following issue is fixed: Memory leaks occur on the processes of resource groups when the memory usage exceeds the upper limit.
The following issue is fixed: Standby Promote takes a long time.
The following issue is fixed: The temporary table parameter in the temporary field of the ***_all_tables view is abnormally displayed.
The following issue is fixed: A memory access out of bounds error is recorded in audit logs.
The following issue is fixed: When you use a database link that connects a PolarDB-O database to an Oracle database to query data, the query result is truncated.
The bug of subpartition pruning based on multi-partition keys for partitioned tables is fixed.

Ganos (V3.3)

Category Feature Description References
New ST_JaccardSimilarity function The ST_JaccardSimilarity function is added to calculate the similarity between trajectories. ST_JaccardSimilarity
ST_Transform function The ST_Transform function is added to transform the coordinates of a trajectory between spatial reference systems. ST_Transform
Optimization Vector pyramid The spatial extent can be specified when a vector pyramid is created. This fixes the issue that the spatial extent cannot be automatically calculated in some scenarios. None
Fixed issues The following issue is fixed: Ganos data catalogs are misconfigured in some environments.

December 2020

Minor version of the kernel (V1.1.7)

Category Feature Description References
New Partitioned table The Merge Partitions feature is added to merge two partitioned tables.
Compatibility with decoding in Oracle Base64 decoding used in Oracle is supported. The BASE64_DECODE function can automatically identify an invalid encoded string and decode the first valid part of the string. polar_enable_base64_decode
Date format You can insert or update a date in the yyyymmddhh24miss format. None
SYS.***_TAB_COLS view The SYS.***_TAB_COLS view is added to query columns of tables and views.
polar_utility plug-in The polar_utility plug-in is added. polar_utility
Stored procedure A stored procedure can return a holdable refcursor. None
DBMS_JOB package The DBMS_JOB package is added. You can invoke the package by using a privileged account or across databases. DBMS_JOB
Optimization UTL_ENCODE The UTL_ENCODE plug-in can be used by newly created standard users. UTL_ENCODE
polar_agg plug-in By default, the polar_agg plug-in is enabled. None
fdw plug-in The stability of the fdw plug-in is improved. None
Fixed issues The following issue is fixed: An error occurs when you execute SELECT INTO to query null values in a stored procedure.
The following issue is fixed: The limits become invalid when an index scan is performed after you execute ALTER TABLE… EXCHANGE PARTITION.

Console

Category Feature Description References
New DBLink

A database link from a PolarDB-O database to a self-managed Oracle database hosted on an Elastic Compute Service (ECS) instance is added. This way, you can connect a PolarDB-O database to an Oracle database. You can also connect an Oracle database to a PolarDB-O database by using a database link in Oracle. This implements the interconnection between PolarDB-O and Oracle databases.

To create a database link, on the cluster details page, choose Settings and Management > Databases.

dblink
Create a database link from PolarDB-O to Oracle

Ganos (V3.2)

Category Feature Description References
New ST_AsPNG BYTEA-type images can be returned for vector pyramids. This feature can be used to visualize vector data. ST_AsPNG
Raster data The JPEG 2000 compression algorithm is supported. This algorithm is used to compress 16-bit raster data before the data is stored. None
Optimization st_dwithin The ST_DWithin function is optimized to query distances. This improves the query performance. None
Fixed issues The issue of an improper intersection of trajectories on the t axis is fixed.
The issue of the memory topology index supported by Ganos is fixed.

API

Category Feature Description
Optimization CreateDBLink A database link that connects a PolarDB-O database to a self-managed Oracle database hosted on an ECS instance is supported.

November 2020

Minor version of the kernel (V1.1.6)

Category Feature Description References
New Compatibility The version is compatible with PostgreSQL 11.9. Overview
Switchover between primary and read-only nodes By default, the OnlinePromote feature is enabled. This reduces the time that is consumed by a switchover between primary and read-only nodes and improves cluster availability. Perform a switchover
DBLink A database link is added to connect a PolarDB-O database to another database in another PolarDB-O cluster. Database link overview
Fixed issues The issue that the node restart may be suspended in some scenarios is fixed.
The issue that the cluster does not respond due to out of memory (OOM) errors in some scenarios is fixed.
The issue that read-only nodes do not respond in some scenarios is fixed.
The issue that an error occurs when the UTF8 encoding format is converted into GBK after you run the client_encoding=gbk command is fixed.
The issue that an error occurs when the first parameter of the NVL function is empty is fixed.

Console

Category Feature Description References
New DBLink

A database link is added to connect a PolarDB-O database to another PolarDB-O database. This implements the interconnection between PolarDB-O databases.

To create a database link, on the cluster details page, choose Settings and Management > Databases.

dblink
Database link overview

API

Category Feature Description
New CreateDBLink This operation can be called to create a database link in a PolarDB-O cluster.
DescribeDBLinks This operation can be called to query database links of a PolarDB-O cluster.
DeleteDBLink This operation can be called to delete a database link from a PolarDB-O cluster.

October 2020

Minor version of the kernel (V1.1.5)

Category Feature Description References
New Audit logs Precompiled SQL statements in audit logs can be printed as executable SQL statements. None
Hash partitioning The syntax that is used to create a specified number of hash partitioned tables is added. CREATE TABLE ... PARTITION BY HASH
Partitioned table The name of a partition or subpartition can be specified. This way, you can query data of a specified partition. Query a specified partition
HOST parameter The HOST parameter is supported. In this case, you can obtain the HOST value of a client. None
Optimization Views The query_id field is added to optimize the polar_stat_activity view. None
Compatibility The minor version of the kernel is upgraded to 11.8. Several stability issues are fixed. None
Fixed issues The issue that a semi-synchronization cannot time out is fixed.
The issue that the CONNECT BY statement fails to be used in conjunction with the WITH clause is fixed.

Ganos (V3.1)

Category Feature Description References
New Trajectory data type GiST indexes are supported for trajectories. In addition, six operator families of different dimensions are provided to meet multi-dimensional analysis requirements. None
The BoxND data type is supported. This data type is used to describe the bounding box of a spatio-temporal extent or a storage trajectory. None
The following operators are supported to compare the spatio-temporal relationships between two specified objects from various dimensions: the && operator, the @> operator, and the <@ operator. The && operator is used to check whether the two specified objects intersect. The @> operator is used to check whether the left operand-specified object includes the right operand-specified object. The <@ operator is used to check whether the left operand-specified object is included in the right operand-specified object. None
The ST_ndIntersects, ST_ndDWithin, ST_ndContains, and ST_ndWithin functions are added to process trajectories.
New features are added to collect trajectory statistics. Scan costs can be estimated based on these trajectory statistics. None
TrajGist indexes are added. This provides an optimized indexing method. None
ganos_update function The ganos_update function is added. All the Ganos extensions can be upgraded to the latest version by running the select ganos_update() ; command. None
Optimization Spatio-temporal range query Spatio-temporal range queries are optimized. The query performance is improved by using optimized GiST index-based two-phase queries. None
Vector pyramid feature Source data from all the coordinate systems that provide spatial reference identifiers (SRIDs) is supported. The source data can be tiles that are based on the EPSG:3857 or EPSG:4326 coordinate reference system. None
The pixelSize parameter is added to aggregate point data and reduce the number of tiles. None
Fixed issues The following issue is fixed: Failures occur when Ganos rasters are updated in some scenarios.
The following issue is fixed: A breakdown may occur after the binary files of Ganos are upgraded to later versions.
The following issue is fixed: The data volume of top-level tiles is excessively large after the point data of vector pyramids is built by using the default parameters.

September 2020

Minor version of the kernel (V1.1.4)

Category Feature Description References
New GROUP_ID function The GROUP_ID() function is added. GROUP_ID
Partitioned table The CREATE INDEX CONCURRENTLY statement is supported. This way, you can concurrently create indexes on partitioned tables. None
Making the index of a standard table invisible The ALTER INDEX [NAME] INVISIBLE statement is supported. This way, you can make the index of a standard table invisible. None
ali_decoding plug-in The ali_decoding plug-in is added to synchronize incremental data manipulation language (DML) statements between databases. None
pg_cron plug-in The pg_cron plug-in is supported. This plug-in is used to query the records of scheduled tasks. PG_CRON
to_char() Strings can be specified in the TO_CHAR() function. None
Data type The following operators are added to compare the prid_ data type of the ROWID column with the string data type such as TEXT. The operators are also used to compare the string data type such as TEXT with the prid_ data type of the ROWID column.
  • <
  • <=
  • >
  • >=
  • =
  • <>
None
Views The views of process status are added. None
The views of time consumption statistics for SQL statements are added. None
Audit logs SQL errors are recorded in audit logs. None
Fixed issues The following issue is fixed: Deadlocks may be caused by page prefetching in specific scenarios.
The following issue is fixed: A JOIN query fails to retrieve the accurate partition during partition pruning.

Ganos (V3.0)

Category Feature Description References
New Support for the subset raster in a NetCDF raster file that has multiple subsets The subset raster in a NetCDF raster file that has multiple subsets can be imported by specifying the subset name. None
Custom metadata and time series information about rasters The ST_MetaItems function is added to obtain all the names of custom metadata items. ST_MetaItems
The ST_MetaData function is added to obtain custom metadata items of a raster and return custom metadata items in JSON format. ST_MetaData
The ST_SetMetaData function is added to specify a metadata item. ST_SetMetaData
The ST_BeginDateTime function is added to obtain the start time of a raster. ST_BeginDateTime
The ST_EndDateTime function is added to obtain the end time of a raster. ST_EndDateTime
The ST_SetBeginDateTime function is added to specify the start time of a raster. ST_SetBeginDateTime
The ST_SetEndDateTime function is added to specify the end time of a raster. ST_SetEndDateTime
The ST_SetDateTime function is added to specify the start time and end time of a raster, and the time when a band is obtained. ST_SetDateTime
Support for converting a raster into a BYTEA-type image The ST_AsImage function is added to convert a raster into a BYTEA-type image. ST_AsImage
The ST_AsPng function is added to convert a raster into a BYTEA-type PNG image. ST_AsPNG
The ST_AsJPEG function is added to convert a raster into a BYTEA-type JPEG image. ST_AsJPEG
Support for the GeomGrid data type and operations The GeomGrid data type is added. GeomGrid SQL reference
The ST_AsText function is added to convert a grid into its text representation. ST_AsText
The ST_AsGeometry function is added to obtain the geometric representation of a grid. ST_AsGeometry
The ST_AsBinary function is added to convert a grid into its binary representation. ST_AsBinary
The ST_AsBox function is added to obtain the box representation of a grid. ST_AsBox
The ST_AsGrid function is added to query the grids that intersect with a geometric object. ST_AsGrid
The ST_GridFromText function is added to convert a grid from its text representation into its GeomGrid representation. ST_GridFromText
The ST_GridFromBinary function is added to convert a grid from its binary representation into its GeomGrid representation. ST_GridFromBinary
The ST_Intersects function is added to identify the spatial relationship between two raster objects or between a raster object and a geometric object. This allows you to check whether the first specified object intersects with the second one. ST_Intersects
The ST_Contains function is added to identify the spatial relationship between two raster objects or between a raster object and a geometric object. This allows you to check whether the first specified object contains the second one. ST_Contains
The ST_Within function is added to identify the spatial relationship between two grid objects or between a grid object and a geometric object. This allows you to check whether the first specified object is within the second one. ST_Within
Quick display and storage of vector data The ST_BuildPyramid function is added to build a vector pyramid for a spatial geometry data table to expedite data display. ST_BuildPyramid
The ST_DeletePyramid function is added to delete a vector pyramid for a spatial geometry data table to expedite data display. ST_DeletePyramid
The ST_Tile function is added to obtain vector data in the MVT format. ST_Tile
Fixed issues The following issue is fixed: OOM errors may occur when you create pyramids in some scenarios.
The following issue is fixed: Trajectory objects fail to be created on January 1, 2000.
The following issue is fixed: An invalid trajectory is returned when the ST_Intersection function is used for trajectory objects in some scenarios.
The following issue is fixed: The system stops responding during a Ganos upgrade.
The version is compatible with PostGIS 2.5.4.

August 2020

Minor version of the kernel (V1.1.3)

Category Feature Description References
New Views The views of SQL execution statistics are added. None
The views of queries per second (QPS) statistics are added. None
The views of CGroup status statistics are added. None
polar_superuser permission The SELECT permission on dba_* views is granted to the accounts that have the polar_superuser permission. None
Fixed issues The following issue is fixed: A display error of the polar_stat_io_info view occurs.
The following issue is fixed: The AWR system wait information is missing.
The following issue is fixed: An error occurs during partition pruning.
The following issue is fixed: Errors occur when the Segmented Least Recently Used (SLRU) algorithm is used to calculate the memory size.
The following issue is fixed: Read-only nodes are recreated due to a playback latency.

Ganos (V2.9)

Category Feature Description References
New Support for COG files The Cloud Optimized GeoTIFF (COG) files are supported. The pyramid information that is stored in COG files can be read. None
ST_AddZ function The ST_AddZ function is added to specify the Z coordinate of a geometric object based on the pixel value of the raster that is converted from the geometric object. ST_AddZ
Enhanced capabilities of obtaining the spatial extent information about raster objects The ST_Extent function is added to retrieve the spatial extent of a raster object and return the box representation of the raster object. ST_Extent
The ST_Envelope function is added to retrieve the spatial extent of a raster object and return the spatial extent in the format of a geometric object. ST_Envelope
The ST_ConvexHull function is added to retrieve the spatial extent of a raster object and return the spatial extent in the format of a geometric object. ST_ConvexHull
The ST_Height function is added to retrieve the pixel height of a raster object. ST_Height
The ST_Width function is added to retrieve the pixel width of a raster object. ST_Width
Fixed issues The following issue is fixed: Performance bottlenecks occur when some raster objects that are stored in external storage locations use the chunking dimension of 1 × n. Storage parameters are added for you to customize the size of the chunking dimension.
The following issue is fixed: The returned values are different from the coordinate values when you use the ST_Values function to obtain values in some directions.
The following issue is fixed: The ST_BestPyramidLevel function returns a negative value in some cases.
The following issue is fixed: The ST_BuildPyramid function may repeatedly create pyramids in some cases.
The following issue is fixed: The corresponding block table is not deleted when you truncate a raster table.
The following issue is fixed: The ST_ExportTo function is invalid for CreateOption in some cases.
The following issue is fixed: The ST_ClearChunks function fails if a table name contains uppercase and lowercase letters.
The following issue is fixed: An external pyramid cannot create an overview in some cases.
The following issue is fixed: Raster objects that have external pyramids cannot create internal pyramids.
The following issue is fixed: Invalid results are returned when you calculate the raster data that contains NaN values.

July 2020

Minor version of the kernel (V1.1.2)

Category Feature Description References
New Pivot syntax The Pivot syntax allows you to specify table or subquery as an alias. None
ROWID pseudocolumn The ROWID pseudocolumn and the ROWIDTOCHAR and CHARTOROWID functions are supported. None
Built-in functions The LNNVL, DUMP, SYS_CONTEXT, USERENV, TZ_OFFSET, and VSIZE functions are supported. None
DBMS_JOB and DBMS_SCHEDULER DBMS_JOB and DBMS_SCHEDULER are supported and are used to maintain and manage jobs. None
Temporary tables Temporary tables can be written to local storage. This improves the read and write performance of temporary tables. None
Event trigger Accounts that have the polar_superuser permission can perform logical replication on events that are captured by the event trigger. None
Customized groups for resource isolation Requests can be initiated by customized groups that are used for resource isolation. None
Optimization Process of recovery from a breakdown The process of recovery from a breakdown is optimized. This reduces the amount of time that is required to recover from a breakdown in specific extreme cases. None
Fixed issues The following issue is fixed: Accounts that have the polar_superuser permission cannot use the index advisor.

Ganos (V2.8)

Category Feature Description References
New Enhanced interfaces for accessing raster metadata The ST_XMin function is added to obtain the minimum value in a set of rasters on the X-axis. ST_XMin
The ST_YMin function is added to obtain the minimum value in a set of rasters on the Y-axis. ST_YMin
The ST_XMax function is added to obtain the maximum value in a set of rasters on the X-axis. ST_XMax
The ST_YMax function is added to obtain the maximum value in a set of rasters on the Y-axis. ST_YMax
The ST_ChunkHeight function is added to obtain the height of a raster tile. ST_ChunkHeight
The ST_ChunkWidth function is added to obtain the width of a raster tile. ST_ChunkWidth
The ST_ChunkBands function is added to obtain the number of bands of a raster tile. ST_ChunkBands
ST_SrFromEsriWkt function The ST_SrFromEsriWkt function is added to convert the format of a spatial reference string from Esri into Open Geospatial Consortium (OGC). ST_SrFromEsriWkt
Raster data type Raster data files can be compressed by using the Zstandard (zstd) compression algorithm or the Snappy compression library. None
Point cloud data type Point cloud files can be copied in binary mode. None
Environment variables The PROJ_LIB and GDAL_DATA environment variables can be configured and the related data can be deployed. None
Fixed issues The following issue is fixed: Databases do not respond due to invalid Object Storage Service (OSS) paths.
The following issue is fixed: After some raster data is imported to databases, the SRIDs of the raster data are inconsistent with the original SRIDs.

June 2020

Minor version of the kernel (V1.1.1)

Category Feature Description References
New NVL2 function The NVL2 function is added. This function returns the value of the second or third parameter based on whether the value of the first parameter is NULL or an empty string. None
polar_proxy_utils plug-in The polar_proxy_utils plug-in is added to manage proxy-related features. This plug-in allows you to configure read-only Universal Disk Format (UDF) files and read-only tables. This plug-in also allows you to use a cluster endpoint to route requests of accessing read-only UDF files and read-only tables to read-only nodes in the cluster. None
polar_resource_group plug-in The polar_resource_group plug-in is added to customize resource groups. You can use the customized groups to isolate resources such as CPUs and memory on a per-user, per-database, or per-session basis. None
Optimization Reliability and availability The compute nodes of databases are decoupled from file systems so that you can independently perform operations and maintenance (O&M) on file systems. This improves the reliability and availability of databases. None
Transaction processing The snapshot of the active transaction list is replaced with a commit sequence number (CSN). Each CSN is a monotonically increasing identifier. This improves the transaction processing performance of databases. None
Execution plan The execution plan is optimized to prevent obsolete statistics from being used. None
Fixed issues The following issue is fixed: A database process failure occurs when the timescaledb plug-in fails to request memory resources.
The following issue is fixed: The I/O monitoring feature does not provide data statistics after a process exits.
The following issue is fixed: A null pointer exception may occur after lock_debug is enabled.
The following issue is fixed: The pg_cron plug-in becomes unavailable in specific cases.
The known issue of distributed shared memory (DSM) deadlocks in the community edition is fixed.
The following issue is fixed: The number of connections exceeds the upper limit.

May 2020

Minor version of the kernel (V1.1.0)

Category Feature Description References
New TO_SINGLE_BYTE function The TO_SINGLE_BYTE function is added to convert multi-byte characters in a string into single-byte characters. TO_SINGLE_BYTE and TO_MULTI_BYTE functions
TO_MULTI_BYTE function The TO_MULTI_BYTE function is added to convert single-byte characters in a string into multi-byte characters. TO_SINGLE_BYTE and TO_MULTI_BYTE functions
REGEXP_LIKE function The REGEXP_LIKE function is added. You can use this function in a similar way to the LIKE conditional expression. The REGEXP_LIKE function complies with the POSIX regular expression. None
RATIO_TO_REPORT function The RATIO_TO_REPORT function is added to calculate the ratio of a value to the sum of a set of values. None
DBMS_UTILITY.FORMAT_ERROR_STACK function The DBMS_UTILITY.FORMAT_ERROR_STACK function (macro) is added to return the stack information layer by layer and error messages. None
UTL_I18N.ESCAPE_REFERENCE and UTL_I18N.UNESCAPE_REFERENCE functions The UTL_I18N.ESCAPE_REFERENCE and UTL_I18N.UNESCAPE_REFERENCE functions are added. These functions provide escape and unescape mechanisms for HTML or XML characters. None
INSERT ALL statement The INSERT ALL statement is supported. You can execute the INSERT ALL statement to insert data into multiple tables at a time. None
polar_concurrency_control plug-in The polar_concurrency_control plug-in is added to set a concurrency limit on transaction executions, SQL queries, stored procedures, and DML operations. You can customize large queries and set a concurrency limit on large queries to improve the execution efficiency in high concurrency scenarios. None
pldebugger plug-in The pldebugger plug-in is added to debug on-premises stored procedures. You can use the client pgAdmin 4 4.19 or later. Use the pldebugger plug-in
oss_fdw plug-in The oss_fdw plug-in is added to support external tables of Alibaba Cloud OSS. You can use OSS external tables to write data of databases to OSS or load data from OSS to databases. You can use multiple external tables in parallel or compress data during imports and exports. This improves the performance of data imports and exports. You can also use this feature to separate hot data and cold data that are stored in a wide range of storage media. Read and write foreign data files by using oss_fdw
Optimization ROUND function The ROUND function is optimized to support the Interval data type. The returned values are measured in days. ROUND
polar_stat_activity view The polar_stat_activity view is optimized and the wait_info and wait_time columns are added. The wait_info column displays the object for which the current process is waiting. The wait_time column displays the amount of time that the process needs to wait for. If the object is a process, the process identifier (PID) is displayed. If the object is a file, the file descriptor (FD) is displayed. None
Index The pre-extension feature is added. This feature automatically adds additional index pages when index pages are insufficient for new indexes. This improves the execution performance when data is inserted into a table that has indexes. None

Ganos (V2.7)

Category Feature Description References
New MD5 functions The ST_MD5Sum function is added to obtain the MD5 hash value of a raster object. ST_MD5Sum
The ST_SetMD5Sum function is added to set the MD5 hash value of a raster object. ST_SetMD5Sum
Authentication method of spatial raster objects stored in OSS The ST_AKId function is added to obtain the AccessKey ID of a raster object stored in OSS. ST_AKId
The ST_SetAccessKey function is added to set the AccessKey ID and AccessKey secret of a raster object stored in OSS. ST_SetAccessKey
The ST_SetAKId function is added to set the AccessKey ID of a raster object stored in OSS. ST_SetAKId
The ST_SetAKSecret function is added to set the AccessKey secret of a raster object stored in OSS. ST_SetAKSecret
Functions for managing spatial raster metadata The ST_ScaleX function is added to obtain the pixel width of a raster object on the X-axis of the spatial reference system. ST_ScaleX
The ST_ScaleY function is added to obtain the pixel width of a raster object on the Y-axis of the spatial reference system. ST_ScaleY
The ST_SetScale function is added to set the pixel width of a raster object in the spatial reference system. ST_ScaleY
The ST_SkewX function is added to obtain the skew of a raster object on the X-axis of the spatial reference system. ST_SkewX
The ST_SkewY function is added to obtain the skew of a raster object on the Y-axis of the spatial reference system. ST_SkewY
The ST_SetSkew function is added to set the skew of a raster object in the spatial reference system. ST_SetSkew
The ST_UpperLeftX function is added to obtain the upper-left X-coordinate of a raster object in the spatial reference system. ST_UpperLeftX
The ST_UpperLeftY function is added to obtain the upper-left Y-coordinate of a raster object in the spatial reference system. ST_UpperLeftY
The ST_SetUpperLeft function is added to set the upper-left coordinates of a raster object in the spatial reference system. ST_SetUpperLeft
The ST_PixelWidth function is added to obtain the pixel width of a raster object in the spatial reference system. ST_PixelWidth
The ST_PixelHeight function is added to obtain the pixel height of a raster object in the spatial reference system. ST_PixelHeight
Fixed issues The following issue is fixed: Aggregate functions may result in extension upgrade failures.