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

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

June 2021

Minor version of the kernel (V1.1.13)

Category Feature Description Documentation
Added features Display of I/O statistics in the polar_stat_sql and polar_stat_plan views
  • The relevant resource information can be obtained by querying different views. This helps identify performance issues.
  • Performance diagnostics is supported by PolarDB-O. This allows you to analyze performance issues related to instances and SQL queries.
  • Relevant parameters are supported to display I/O statistics in the polar_stat_sql and polar_stat_plan views.
Views about performance and Performance diagnostics
Cross-node parallel execution Cross-node parallel execution can be used to scan BRIN indexes. This further improves query performance. Overview of cross-node parallel execution
The polar_bt_write_page_buffer_size parameter is supported. This parameter specifies the write I/O policy that is used while an index is being created. Use cross-node parallel execution to accelerate index creation
The following three granularities can be used to specify a query range when you use cross-node parallel execution:
  • System: specifies whether cross-node parallel execution is applied to all the queries that run in all sessions.
  • Session: specifies whether cross-node parallel execution is applied to the current session.
  • Query: specifies whether cross-node parallel execution is applied to specific queries.
Use the cross-node parallel execution feature to run analytical queries
Cross-node parallel execution can be used for partitioned tables to improve database performance. Use the cross-node parallel execution feature to query data from partitioned tables
Optimized features polar_crash_recovery_rto parameter The polar_crash_recovery_rto parameter is supported. This parameter specifies an expected Recovery Time Objective (RTO) for an instance. This ensures that the databases on the instance can restart for recovery and become available within the expected RTO when a breakdown occurs. None

Ganos (V3.8)

Category Feature Description Documentation
Added features ST_AsDatasetFile function The ST_AsDatasetFile function is supported. This function is used to return a specified range of raster objects as a binary stream in the specified file format. None
ST_RasterDrivers function The ST_RasterDrivers function is supported. This function is used to query the status of all raster data drivers. None
Fixed issues The following issue is fixed: A reprojection failure occurs when you use the ST_Clip function to specify a spatial reference system for the reprojection.

May 2021

Minor version of the kernel (V1.1.12)

Category Feature Description Documentation
Added features Cross-node parallel execution Cross-node parallel execution is supported.
  • Allows you to run SQL queries across multiple read-only nodes in a distributed manner. This improves the query performance of PolarDB-O.
  • Allows you to use cross-node parallel execution to accelerate the process of creating indexes. This allows you to create indexes in large table scenarios in a more efficient manner.
Cross-node parallel execution
Support of partitioned tables for global indexes Global indexes can be created on partitioned tables. Indexes can be created in parallel. This means that DML operations on a partitioned table are not blocked while an index is being created on the table. None
Optimized features Performance monitoring The max_slot_wal_keep_size parameter is supported. This parameter is used to limit the size of files that use replication slots. This can prevent Write-Ahead Logging (WAL) files from accumulating. None
DBLink By default, functions that do not meet collation requirements and ANY() and ALL() expressions can be pushed down. This improves query performance. You can use the polar_enable_pushable_unsafe_collate_remote and polar_enable_pushable_all_any_remote parameters to disable these settings. Use a database link to query data across databases
Rownum ROWNUM is optimized so that ROWNUM values can be compared with the values of the VARCHAR2 or TEXT type. None
polar_resource_group plug-in Multiple parameters including total_mem_limit_remain_size, idle_mem_limit_rate, enable_terminate_active, policy_mem_release, and enable_log are supported to configure the polar_resource_group plug-in. This avoids excessive usage of memory and ensures the normal running of database processes. None
Improved startup speed of read-only nodes The startups of read-only nodes are speeded up. This improves performance. None
Primary/secondary switchover The parallel playback feature can be used to accelerate the recovery of database services after a primary/secondary switchover. In most cases, the database services can be recovered within 15 seconds when a primary database fails. None

Ganos (V3.7)

Category Feature Description Documentation
Added features Spatio-temporal parallel query Spatial indexes can be queried in parallel. This improves query efficiency. Enable spatio-temporal parallel query
Optimized features Raster image processing The ST_SubRaster function can be used to convert the pixel types of raster objects and stretch the pixel values. Raster image processing can be applied to AI recognition scenarios in which multi-band remote sensing images are converted to three-band images. ST_SubRaster
Fixed issues The following issue is fixed: A database may break down when you perform a raster data analysis on invalid histogram information.
The following issue is fixed: After a specified raster dataset is transformed into another projection, a breakdown may occur when you disconnect from your database.
The following issue is fixed: A database may break down when you import raster data to the database.

April 2021

Minor version of the kernel (V1.1.11)

Category Feature Description Documentation
Added features idle_session_timeout parameter

The idle_session_timeout parameter is supported. This parameter specifies the period during which sessions can remain idle before the sessions time out. Sessions are terminated after they time out.

  • Valid values: 0 to 2147483647

    The default value of 0 specifies that the idle session timeout feature is disabled.

  • Unit
    • 'ms': millisecond. This is the default unit.
    • 's': second.
    • 'min': minute.
    • 'h': hour.
    • 'd': day.
Specify parameters
DDL operation related to constraints The ALTER TABLE ... ENABLE/DISABLE CONSTRAINT SQL statement is supported. This statement can be used to enable or disable constraints. ALTER TABLE ... ENABLE/DISABLE CONSTRAINT
DDL operations related to tablespaces DDL operations related to tablespaces are supported. For example, CREATE TABLESPACE can be executed to create tablespaces. None
Numeric data types Compatible with the numeric data types of Oracle. You can enable this feature by specifying the polar_enable_comp_numeric_format parameter. By default, this feature is disabled. To enable this feature, execute the following statement:
SET polar_enable_comp_numeric_format=on;
None
Fixed issues The following issue is fixed: The built-in DBMS_JOB package cannot be used across databases.
The following issue is fixed: The CONNECT BY and ROWNUM functions cannot be used together.
The following issue is fixed: The CONNECT BY function cannot find parent objects.

Ganos (V3.6)

Category Feature Description Documentation
Added features Raster data type The ST_RPCGeoreference function is supported. This function is used to retrieve the information about the rational polynomial coefficients (RPCs) of a raster object. ST_RPCGeoreference
The ST_SetRPCGeoreference function is supported. This function is used to specify RPC parameters for a raster object. ST_SetRPCGeoreference
The ST_RPCRectify function is supported. This function is used to rectify a raster object based on the RPC parameters and return the updated raster object. ST_RPCRectify
GiST indexing GiST indexes can be created in parallel. Create spatial indexes in parallel
Fixed issues The following issue is fixed: When you use the pg_dump utility, custom spatial references cannot be exported.

March 2021

Minor version of the kernel (V1.1.10)

Category Feature Description Documentation
Added features 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. None
Optimized features Partitioned table Subpartition templates can be used for interval range partitioning. Subpartition templates
Performance optimization The read performance of data files is optimized. You can cache the information about table sizes in shared memory to optimize the read performance. None
Compatibility The following operators are supported by INTERVAL and FLOAT8 data types:
  • +
  • -
  • *
  • /
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. OPT_PARAM Hints

Ganos (V3.5)

Category Feature Description Documentation
Added features Storage optimization for large spatio-temporal objects The Simple storage policy is supported. This policy optimizes storage for large spatio-temporal objects. Use the Simple storage policy
Optimized features Raster object The chunked data in the original raster object can be automatically deleted. 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: In some cases, an error occurs when a raster object is resampled by using the average resampling method.
The following issue is fixed: If the trajectory points for multiple timestamps are the same in a trajectory object, query results may be invalid.
The following issue is fixed: The conversion process is terminated after a GEOS object fails to be converted. After this issue is fixed, the system also prompts the causes of a conversion failure.

Minor version of the kernel (V1.1.9)

Category Feature Description Documentation
Added features 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-partitioned tables can be converted to interval-range partitioned tables. Interval-range partitioned tables can be converted to range-partitioned tables. Switch between range partitioning and interval range partitioning
Subpartition templates are supported. You can use subpartition templates to define subpartitions and simplify the specifications of subpartitions. You need only to define subpartition descriptors in a subpartition template once 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
Automatic Workload Repository (AWR) for performance monitoring AWR is supported. AWR collects and analyzes performance statistics. You can use AWR to generate an analytical report for a specified period based on statistics such as dynamic views of a database. This allows you to analyze the database performance within the specified period. None
Optimized features Partitioned table Partition pruning is enabled in the execution plan for a partitioned table. This improves query performance. None
Data type PolarDB O Edition 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 Edition and Oracle, the system automatically converts a DATE value into a TIMESTAMP(0) value. None
WAL The pipeline technology is supported. This technology is used to reduce the proportion of WAL overhead. This can improve overall system performance. None
TO_CHAR TO_CHAR(text1, text2) is supported. This function automatically identifies the data type of text1 and text2 on the server side. If text1 and text2 are valid DATE values, the function automatically converts text1 into a TIMESTAMP value. None
Fixed issues Invalid 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 invalid parameters are specified.
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 Documentation
Added features 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. The polar_enable_storage_partial parameter is also supported. 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 is supported. This function is used to import raster data in parallel. ST_ImportFrom
The ST_BuildPyramid function is supported. This function is used to create pyramids in parallel based on raster data. ST_BuildPyramid
Trajectory Empty The Trajectory Empty object is supported. This allows null objects to be returned if requirements are not met in some scenarios. None
Fixed issues The following issue is fixed: When the input parameter is a 16-bit signed integer (16BSI), the ST_AddZ function may return an invalid result.
The following issue is fixed: In some cases, the trajectory module fails to be upgraded.
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 Documentation
Added features DBMS_STATS plug-in The DBMS_STATS plug-in is supported. You can use this plug-in to collect relevant statistics while 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 that are 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
Optimized features 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 the 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 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 configuration of a partitioned table 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
User 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: When logical replication is used to synchronize the DBMS_JOB tables that do not have primary keys, tasks fail to be deleted.
The following issue is fixed: When the memory usage exceeds the upper limit, memory leaks occur in the processes of resource groups.
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 Documentation
Added features ST_JaccardSimilarity function The ST_JaccardSimilarity function is supported. This function is used to calculate the similarity between trajectories. ST_JaccardSimilarity
ST_Transform function The ST_Transform function is supported. This function is used to transform the coordinates of a trajectory between spatial reference systems. ST_Transform
Optimized features Vector pyramid The spatial extent can be specified when you create a vector pyramid. This fixes the issue that the spatial extent of a vector pyramid 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 Documentation
Added features 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 Dates in the YYYYMMDDHH24MISS format can be inserted or updated. None
SYS.***_TAB_COLS view The SYS.***_TAB_COLS view is supported. This view can be used to query columns of tables and views.
polar_utility plug-in The polar_utility plug-in is added. polar_utility
Stored procedure Holdable refcursors can be returned by stored procedures. 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
Optimized features UTL_ENCODE The UTL_ENCODE plug-in can be used by newly created standard users. UTL_ENCODE
polar_agg plug-in The polar_agg plug-in is enabled by default. 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 constraints become invalid when an index scan is performed after you execute ALTER TABLE… EXCHANGE PARTITION.

Console

Category Feature Description Documentation
Added features DBLink

A database link from a PolarDB-O database to a self-managed Oracle database hosted on an Elastic Compute Service (ECS) instance is supported. 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, choose Settings and Management > Databases on the cluster details page.

dblink
Create a database link from to PostgreSQL

Ganos (V3.2)

Category Feature Description Documentation
Added features 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
Optimized features st_dwithin The ST_DWithin function is optimized to query distances. This improves the query performance. None
Fixed issues The following issue is fixed: The intersection of trajectories on the t axis is improper.
The issues related to the memory topology indexes that are supported by Ganos are fixed.

API

Category Feature Description
Optimized features CreateDBLink A database link that connects a PolarDB O Edition 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 Documentation
Added features Compatibility This kernel version is compatible with PostgreSQL 11.9. What is ?
Primary/secondary switchover By default, the OnlinePromote feature is enabled. This feature reduces the amount of 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 supported to connect a PolarDB-O database to another database in another PolarDB-O cluster. Database link overview
Fixed issues The following issue is fixed: A node does not restart smoothly in some scenarios.
The following issue is fixed: In some scenarios, clusters do not respond due to out of memory (OOM) errors.
The following issue is fixed: In some scenarios, read-only nodes do not respond.
The following issue is fixed: An error occurs when the UTF-8 encoding format is converted into GBK after you run the client_encoding=gbk command.
The following issue is fixed: An error occurs when the first parameter of the NVL function is left empty.

Console

Category Feature Description Documentation
Added features DBLink

A database link can be created to connect a PolarDB-O database to another PolarDB-O database. This allows you to access data across PolarDB-O databases.

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

dblink
Database link overview

API

Category Feature Description
Added features CreateDBLink This operation can be called to create a database link for 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 Documentation
Added features Audit logs Precompiled SQL statements in audit logs can be displayed 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 when you query data of a specific partition. Query a specified partition
HOST parameter The HOST parameter is supported so that you can obtain the HOST value of a client. None
Optimized features Views The query_id field is added to optimize the polar_stat_activity view. None
Compatibility The minor version of the kernel is updated to 11.8. Several stability issues are fixed. None
Fixed issues The following issue is fixed: A semi-synchronization cannot time out.
The following issue is fixed: The CONNECT BY statement fails to be used in conjunction with the WITH clause.

Ganos (V3.1)

Category Feature Description Documentation
Added features 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 supported to process trajectories.
Trajectory statistics can be collected. Scan costs can be estimated based on these trajectory statistics. None
TrajGist indexes are supported. This provides an optimized indexing method. None
ganos_update function The ganos_update function is supported. You can run the select ganos_update() ; command to upgrade all Ganos extensions to the latest version. None
Optimized features 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 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 supported. This parameter is used to aggregate point data and reduce the number of tiles. None
Fixed issues The following issue is fixed: Ganos rasters fail to be 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 Documentation
Added features GROUP_ID function The GROUP_ID() function is supported. GROUP_ID
Partitioned table The CREATE INDEX CONCURRENTLY statement is supported. This way, you can concurrently create indexes on partitioned tables. None
Support for 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 supported. This plug-in is used to synchronize incremental 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 a string data type such as TEXT. These operators are also used to compare a 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: In specific scenarios, deadlocks may be caused by page prefetching.
The following issue is fixed: A JOIN query fails to retrieve the accurate partition during partition pruning.

Ganos (V3.0)

Category Feature Description Documentation
Added features 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. You can specify the subset name to import the subset raster. None
Custom metadata and time series information of rasters The ST_MetaItems function is supported. This function is used to obtain the names of all custom metadata items. ST_MetaItems
The ST_MetaData function is supported. This function is used to obtain custom metadata items of a raster and return custom metadata items in the JSON format. ST_MetaData
The ST_SetMetaData function is supported. This function is used to specify a metadata item. ST_SetMetaData
The ST_BeginDateTime function is supported. This function is used to obtain the start time of a raster. ST_BeginDateTime
The ST_EndDateTime function is supported. This function is used to obtain the end time of a raster. ST_EndDateTime
The ST_SetBeginDateTime function is supported. This function is used to specify the start time of a raster. ST_SetBeginDateTime
The ST_SetEndDateTime function is supported. This function is used to specify the end time of a raster. ST_SetEndDateTime
The ST_SetDateTime function is supported. This function is used 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 supported. This function is used to convert a raster into a BYTEA-type image. ST_AsImage
The ST_AsPng function is supported. This function is used to convert a raster into a BYTEA-type PNG image. ST_AsPNG
The ST_AsJPEG function is supported. This function is used 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 supported. GeomGrid SQL reference
The ST_AsText function is supported. This function is used to convert a grid into a text representation. ST_AsText
The ST_AsGeometry function is supported. This function is used to obtain the geometric representation of a grid. ST_AsGeometry
The ST_AsBinary function is supported. This function is used to convert a grid into a binary representation. ST_AsBinary
The ST_AsBox function is supported. This function is used to obtain the box representation of a grid. ST_AsBox
The ST_AsGrid function is supported. This function is used to query the grids that intersect with a geometric object. ST_AsGrid
The ST_GridFromText function is supported. This function is used to convert a grid from a text representation into a GeomGrid representation. ST_GridFromText
The ST_GridFromBinary function is supported. This function is used to convert a grid from a binary representation into a GeomGrid representation. ST_GridFromBinary
The ST_Intersects function is supported. This function is used to identify the spatial relationship between two raster objects or between a raster object and a geometric object. This function allows you to check whether the first specified object intersects with the second one. ST_Intersects
The ST_Contains function is supported. This function is used to identify the spatial relationship between two raster objects or between a raster object and a geometric object. This function allows you to check whether the first specified object contains the second one. ST_Contains
The ST_Within function is supported. This function is used to identify the spatial relationship between two grid objects or between a grid object and a geometric object. This function allows you to check whether the first specified object is within the second one. ST_Within
Rapid display and storage of vector data The ST_BuildPyramid function is supported. This function is used to build a vector pyramid for a spatial geometry data table to expedite data display. ST_BuildPyramid
The ST_DeletePyramid function is supported. This function is used to delete a vector pyramid for a spatial geometry data table to expedite data display. ST_DeletePyramid
The ST_Tile function is supported. This function is used to obtain vector data in the MVT format. ST_Tile
Fixed issues The following issue is fixed: In some cases, OOM errors may occur when you create pyramids.
The following issue is fixed: Trajectory objects cannot be created on January 1, 2000.
The following issue is fixed: In some scenarios, an invalid trajectory is returned when the ST_Intersection function is used for trajectory objects.
The following issue is fixed: The system stops responding during a Ganos upgrade.
This version is compatible with PostGIS 2.5.4.

August 2020

Minor version of the kernel (V1.1.3)

Category Feature Description Documentation
Added features 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
Privileged account The SELECT permissions on dba_* views are granted to the accounts that have the polar_superuser permissions. 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 for a partitioned table.
The following issue is fixed: An error occurs 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 Documentation
Added features Support for Cloud Optimized GeoTIFF (COG) files The 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 supported. This function is used 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 for obtaining the spatial extent information about raster objects The ST_Extent function is supported. This function is used 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 supported. This function is used 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 supported. This function is used 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 supported. This function is used to retrieve the pixel height of a raster object. ST_Height
The ST_Width function is supported. This function is used 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: In some cases, the ST_BestPyramidLevel function returns a negative value.
The following issue is fixed: In some cases, the ST_BuildPyramid function may repeatedly create pyramids.
The following issue is fixed: The block table of a raster table is not deleted when you truncate the raster table.
The following issue is fixed: The ST_ExportTo function is invalid for CreateOption in some cases.
The following issue is fixed: If a table name contains uppercase and lowercase letters, the ST_ClearChunks function fails.
The following issue is fixed: In some cases, an external pyramid cannot create an overview.
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 Documentation
Added features Pivot syntax An alias can be specified for a table or a subquery in the Pivot syntax. 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. They 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 Logical replication can be performed on events captured by the event trigger. Accounts that have the polar_superuser permissions can perform logical replication. None
Customized groups for resource isolation Requests can be initiated by customized groups that are used for resource isolation. None
Optimized features 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 permissions cannot use the index advisor.

Ganos (V2.8)

Category Feature Description Documentation
Added features Enhanced interfaces that are used to access raster metadata The ST_XMin function is supported. This function is used to obtain the minimum value in a set of rasters on the X-axis. ST_XMin
The ST_YMin function is supported. This function is used to obtain the minimum value in a set of rasters on the Y-axis. ST_YMin
The ST_XMax function is supported. This function is used to obtain the maximum value in a set of rasters on the X-axis. ST_XMax
The ST_YMax function is supported. This function is used to obtain the maximum value in a set of rasters on the Y-axis. ST_YMax
The ST_ChunkHeight function is supported. This function is used to obtain the height of a raster tile. ST_ChunkHeight
The ST_ChunkWidth function is supported. This function is used to obtain the width of a raster tile. ST_ChunkWidth
The ST_ChunkBands function is supported. This function is used to obtain the number of bands of a raster tile. ST_ChunkBands
ST_SrFromEsriWkt function The ST_SrFromEsriWkt function is supported. This function is used 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 relevant 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 Documentation
Added features NVL2 function The NVL2 function is supported. This function is used to return 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 supported. This plug-in is used 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 for accessing read-only UDF files and read-only tables to the read-only nodes in the cluster. None
polar_resource_group plug-in The polar_resource_group plug-in is supported. This plug-in is used to customize resource groups. You can use the custom resource groups to isolate resources such as CPUs and memory on a per-user, per-database, or per-session basis. None
Optimized features Reliability and availability The compute nodes of databases are decoupled from file systems so that you can independently perform O&M operations on the 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 Execution plans are 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: In specific cases, the pg_cron plug-in becomes unavailable.
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 Documentation
Added features TO_SINGLE_BYTE function The TO_SINGLE_BYTE function is supported. This function is used 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 supported. This function is used 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 supported. You can use this function in a way similar to how the LIKE conditional expression is used. The REGEXP_LIKE function complies with the POSIX regular expression standard. None
RATIO_TO_REPORT function The RATIO_TO_REPORT function is supported. This function is used 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 supported. This function is used to return the stack information and error messages layer by layer. None
UTL_I18N.ESCAPE_REFERENCE and UTL_I18N.UNESCAPE_REFERENCE functions The UTL_I18N.ESCAPE_REFERENCE and UTL_I18N.UNESCAPE_REFERENCE functions are supported. 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 supported. This plug-in is used to configure a concurrency limit on transaction executions, SQL queries, stored procedures, and DML operations. You can customize large queries and configure a concurrency limit on large queries to improve the execution efficiency in high concurrency scenarios. None
pldebugger plug-in The pldebugger plug-in is supported. This plug-in is used to debug local 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 supported. This plug-in is used to support foreign tables of Alibaba Cloud OSS. You can use OSS foreign tables to write data of databases to OSS or load data from OSS to databases. You can use multiple foreign 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
Optimized features 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. 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 for which the process needs to wait. 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 supported. 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 Documentation
Added features MD5 functions The ST_MD5Sum function is supported. This function is used to obtain the MD5 hash value of a raster object. ST_MD5Sum
The ST_SetMD5Sum function is supported. This function is used to configure the MD5 hash value of a raster object. ST_SetMD5Sum
Authentication method of spatial raster objects that are stored in OSS The ST_AKId function is supported. This function is used to obtain the AccessKey ID that is used to access a raster object stored in OSS. ST_AKId
The ST_SetAccessKey function is supported. This function is used to configure the AccessKey ID and the AccessKey secret that are used to access a raster object stored in OSS. ST_SetAccessKey
The ST_SetAKId function is supported. This function is used to configure the AccessKey ID that is used to access a raster object stored in OSS. ST_SetAKId
The ST_SetAKSecret function is supported. This function is used to configure the AccessKey secret that is used to access a raster object stored in OSS. ST_SetAKSecret
Functions that are used to manage spatial raster metadata The ST_ScaleX function is supported. This function is used 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 supported. This function is used 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 supported. This function is used to configure the pixel width of a raster object in the spatial reference system. ST_ScaleY
The ST_SkewX function is supported. This function is used to obtain the skew of a raster object on the X-axis of the spatial reference system. ST_SkewX
The ST_SkewY function is supported. This function is used to obtain the skew of a raster object on the Y-axis of the spatial reference system. ST_SkewY
The ST_SetSkew function is supported. This function is used to set the skew of a raster object in the spatial reference system. ST_SetSkew
The ST_UpperLeftX function is supported. This function is used to obtain the upper-left X-coordinate of a raster object in the spatial reference system. ST_UpperLeftX
The ST_UpperLeftY function is supported. This function is used to obtain the upper-left Y-coordinate of a raster object in the spatial reference system. ST_UpperLeftY
The ST_SetUpperLeft function is supported. This function is used to configure the upper-left coordinates of a raster object in the spatial reference system. ST_SetUpperLeft
The ST_PixelWidth function is supported. This function is used to obtain the pixel width of a raster object in the spatial reference system. ST_PixelWidth
The ST_PixelHeight function is supported. This function is used 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.