Maintenance Release Changelog

Bugfix: Fixed an issue where left join returned the wrong result when spilling occurred.

Enhancement: Update to certificate loading behavior. Prior to this change, only the first certificate was loaded from a server's .pem file specified via the server configuration. Now all certificates are loaded, so if a .pem file contains a certificates chain, then intermediate CA certificates will be returned by the server.

Enhancement: Updated the distributed OpenSSL license file to to 1.0.2zj.

Enhancement: Added a new engine variable: assume_udfs_deterministic. This variable controls behavior where SingleStore will do extra work to avoid issues caused by UDFs that return different values when repeatedly invoked (e.g., are non-deterministic). This variable defaults to false, preserving the existing behavior (since SingleStore version 8.0), where SingleStore will ensure these computations take place once on an aggregator node. When set to true, SingleStore will avoid this extra layer of coordination (and bottleneck) allowing leaf nodes to independently coordinate.

Bugfix: Fixed a rare race condition where PITR would incorrectly operate on an unrecoverable database.

Bugfix: Fixed a wrong results issue in the combination of ShuffleGroupBy and EncodedGroupBy query plan operations.

Enhancement: Added a new engine variable, sampling_estimate_approach, used to configure sampling in columnstore tables.

See Statistics and Sampling Concepts for more information.

Bugfix: Fixed an issue that could occur when replacing JSON expressions with computed columns in GROUP BY lists.

Bugfix: Fixed an issue that could cause scans using non-unique indexes to return wrong results or to crash.

Bugfix: Fixed an issue in parsing manifest files that have more than 4096 characters.

Bugfix: Fixed an issue where user defined variables could read collation-related variables incorrectly during a SET @var = ... command.

Enhancement: Enabled log_file_size_partitions and log_file_size_ref_dbs engine variables on SingleStore Helios.

Bugfix: Unneeded sort fields will no longer be projected to the aggregator.

Bugfix: Fixed an edge case where unlimited storage garbage collection was causing the master aggregator to run out of connections.

Bugfix: Fixed an issue to now avoid prematurely assigning column reference to namespace.

Bugfix: Fixed incorrect results in an uncommon scenario where hash join operators with an optimization path need to spill.

Enhancement: The memsql_exporter now collects additional fields from the mv_activities_extended_cumulative information schema view.

Bugfix: Fixed a crash that occurred when spilling a hash join operation with at least 3 tables.

Enhancement: Improved performance related to PIPELINES_BATCHES information schema table.

Enhancement: Added the enable_use_of_stale_incremental_stats engine variable which allows the optimizer to use stale stats instead of querying for stats during optimization.

Enhancement: Added the throttle_replay_behind_tail_mb engine variable which controls how far the system allows a child aggregator to lag behind replicating the transaction log of its master aggregator before throttling is applied to the master aggregator.

Bugfix: Fixed an issue in ALTER TABLE when adding a computed column containing JSON_BUILD_OBJECT.

Bugfix: Addressed a crash issue with REGEX_REPLACE.

Bugfix: Reduced stack usage during compilation for some CASE expressions with many WHEN-THEN statements.

Bugfix: Fixed a potential deadlock issue between background garbage collector threads and foreground query execution threads.

Enhancement: Upgraded OpenSSL 1.0.2u to 1.0.2zj

Bugfix: Improved the hashGroupBy spilling condition to trigger (spill) when appropriate.

Enhancement: Improved memory management for Resource Pools.

Added the QUERY_MEMORY_PERCENTAGE option for resource pools, which restricts memory usage in the pool on a per-individual query basis. This in contrast to MEMORY_PERCENTAGE which restricts usage based on total memory used within the current pool.

For example, when creating or altering a resource pool, setting MEMORY_PERCENTAGE to 60% and QUERY_MEMORY_PERCENTAGE to 50% would configure the system so that all queries running within the specified resource pool should together use a maximum of 60% of system memory, and any single query running within the pool should use, at most, 50% of system memory. Example syntax:

CREATE RESOURCE POOL rpoolmain WITH
   MEMORY_PERCENTAGE = 60,
   QUERY_MEMORY_PERCENTAGE = 50, 
   SOFT_CPU_LIMIT_PERCENTAGE = 65,
   MAX_CONCURRENCY = 40;

Enhancement: Allow Kerberos users to skip password validation for users who are authenticated with plugins.

Bugfix: Addressed a crash issue occurring while executing queries with vector builtins on clusters running via Docker containers on Mac machines equipped with Apple silicon processors (M1).

Bugfix: Fixed an issue that caused rare "Arrangement already exists in namespace" errors in recursive CTE queries.

Bugfix: Fixed a case where a killed query could incorrectly return a JSON error rather than query interrupted message.

Bugfix: MV_DISK_USAGE queries can no longer block garbage collection.

Bugfix: Fixed a crash-on-startup issue on RHEL-based operating systems/kernels (CentOS 9, RHEL, etc.).

Bugfix: Fixed a crash that could occur when a scalar subselect is passed as an argument to an external TVF.

Enhancement: Added checks to properly handle some corner cases of KAFKA JSON messages.

Bugfix: Fixed an issue with restoring from public backups.

Enhancement: Subprocess and S3 API tracing are now also enabled via the enable_subprocess_tracing engine variable.

Bugfix: Fixed an issue where a log entry ("Skip reading connection attributes") was being written too often.

Bugfix: Fixed a JSON insertion failure to old utf8 sample tables that contain utf8mb4 characters by encoding it with base64 format beforehand for backward compatibility.

Bugfix: The rule based optimization warning message will only be shown when cost based optimization is meaningful.

Bugfix: Fixed a very rare deadlock between ALTER of a table and a DROP of a database.

Bugfix: Fixed an issue with a blob file leak in a rare crash scenario.

Bugfix: Fixed a potential deadlock in a scenario involving DDL, a 2PC transaction, and a concurrent failover.

Bugfix: Removed an unnecessary metadata copy to improve JSON performance.

Bugfix: Fixed an issue where SingleStore would fall back to heuristic estimates instead of histogram estimates when the table is too large to sample.

Bugfix: Fixed an issue in background merger that allowed concurrent deletes of empty segments.

Enhancement: Updated timezone data, now using IANA's tzdata version 2024a; new timezones Kyiv, Ciudad_Juarez, and Kanton supported.

Enhancement: Enabled additional query hint for non-distributed queries so that first run of those queries can be queued.

Bugfix: Fixed a regression with sparse JSON when use_seekable_json is disabled.

Enhancement: Added numInferredPaths and schemaSize as new columns to JSON_COLUMN_SCHEMA table. numInferredPaths is the number of key paths inferred for the segment. schemaSize is the size of schema_json in bytes.

Bugfix: Added safety checks around dropping databases without exclusive access to storage.

Enhancement: Added spilling metrics for TopSort (ORDER BY with LIMIT).

Bugfix: The existing websocket connection will be closed when variables are updated in global scope.

Bugfix: Removed the hardcoded 'collation_server' from constant.StrictModeParams.

Enhancement: Added new metrics to memsql_exporter based on information_schema.mv_sysinfo_disk columns.

Bugfix: Fixed a potential data leak in out-of-memory reports.

Bugfix: Fixed an issue in backup restore when the backup has a corrupted GV timestamp in the about snapshot record.

Bugfix: Fixed an issue with exporter not working with Public-Key Cryptography Standards #8(PKCS#8) pem format.

Bugfix: Fixed an issue with hex() not handling decimal types correctly.

Bugfix: Fixed a crash that occurred when trying to grant access to the table with no context database in per-privilege mode.

Enhancement: Added logging to heartbeat thread in order to better diagnose process stalls. This logging is enabled/disabled via the new verbose_time_heartbeat_thread engine variable. The default value is off, setting this to on will enable the logging.

Bugfix: Fixed an issue in backup restore when the backup has a corrupted GV timestamp in the about snapshot record.

Bugfix: Addressed a family of issues relating to optimal execution of JSON extracts on schema'd data.

Enhancement: The new engine variable parametrize_json_keys allows JSON keys to be parametrized and plans can be reused.

Bugfix: Fixed the change to aggregator activity queries in memsql_exporter not being applied properly.

Enhancement: Reduced amount of memory used by unlimited storage file listing, including point-in-time recovery (PITR).

Enhancement: Added an engine variable, innodb_lock_wait_timeout. This variable exists for backwards compatibility with MySQL and is non-operational in SingleStore Helios.

Enhancement: Backups now throttle after the snapshot.

BugFix: Fixed an issue where a backup would carry metadata about the retention period of the backed up unlimited storage database.

Enhancement: Added ability to memsql_exporter to always return all sub-activities of an aggregator activity.

Enhancement: Improved ability to configure librdkafka through credentials.

Enhancement: Added the column name to the error message when an invalid date/time is inserted into a column.

Enhancement: The new engine variable max_table_memory_room_mb sets the maximum amount of memory required when creating or attaching a database. Configuring this engine variable allows more control over whether a detached database can be reattached.

Enhancement: Increased the maximum value to 15 for the backup_multipart_upload_concurrency engine variable.

Bugfix: Fixed a segmentation fault (crash) from appearing after terminating a query on the remote node.

Bugfix: Fixed the out of memory issue caused by operators generated for wide user tables during the optimization phase.

Bugfix: Fixed an issue where the incorrect number of rows would be shown when performing a select into object storage.

Bugfix: Fixed an issue with FROM_BASE64 and TO_BASE64 built-ins when processing large string inputs, preventing potential errors in reading communication packets.

Bugfix: Fixed an issue with START PIPELINE FOREGROUND skipping files in some circumstances.

Enhancement: Improved error messages when downloading backups.

Enhancement: Added the blob_cache_miss_b and blob_cache_wait_time_ms columns to the following information schema views: information_schema.plancache, information_schema.MV_ACTIVITIES, information_schema.MV_ACTIVITIES_CUMULATIVE, information_schema.MV_TASKS, information_schema.MV_FINISHED_TASKS, and information_schema.MV_QUERY_ACTIVITIES_EXTENDED_CUMULATIVE.

Bugfix: Fixed an issue where INSERT...SELECT queries with a partition_id() filter generating an error.

Bugfix: Fixed an issue with memory crashing when using REGEXP_MATCH, JSON_INCLUDE_MASK, or JSON_EXCLUDE_MASK built-ins.

Enhancement: Improved performance for JSON_EXTRACT_<type> built-ins in ORDER BY clauses.

Enhancement: Added the ability for users to kill queries on a remote node without the user having PROCESS privileges.

Bugfix: Fixed an allocation issue that caused poor performance on high load insertion queries.

Bugfix: Fixed an issue with memsql_exporter working improperly in ANSI_QUOTES sql_mode.

Enhancement: ALTER PIPELINE setting max_partitions_per_batch to use a default 0 value is now allowed.

Bugfix: JSON_KEY escape characters were not working as expected.

Enhancement: Added the bottomless_experimental_blobstore_mode engine variable, which when enabled, completes additional verification of persisted files immediately after upload. This mode is experimental and may reduce upload speed. Please use with caution.

Enhancement: Introduced blob cache profiling metrics for columnstore tables on unlimited storage databases. Refer to the PROFILE page for more information on what blob cache metrics are available.

Bugfix: Fixed a bug which corrupts databases whose log size is not a power of two pages.

Enhancement: Updated the information_schema.USERS view to reflect the account status for locked users.

Bugfix: Fixed a crash that occurred when user-defined variables are used in the GROUP BY and ORDER BY clauses.

Bugfix: Fixed an issue where filtering with a JSON_EXTRACT_<type> function performs inconsistently.

Bugfix: Fixed a network communication error that occurred after query rewrites.

Bugfix: Fixed an issue where JSON computed column matching incorrectly triggers a JSON_EXTRACT_<type> function.

Bugfix: Modified computed column matching to accurately evaluate JSON expressions containing equality and non-safe equality comparisons.

Bugfix: Fixed an error that occurred when a user attempts to access a view that is based on a table that has no privileges granted on it.

Enhancement: Improved the ability to kill queries containing JSON built-in functions.

Enhancement: The query optimizer now considers more LEFT JOINelimination cases.

Enhancement: Introduced a new session engine variable optimizer_disable_transitive_predicates which disables predicate transitivity on query rewrites.

Enhancement: Added more log messages for backup sub-process errors.

Added support for creating a DEEP COPY of tables with computed columns. (8.1.31)

Added additional config and credential option validation while creating pipelines. (8.1.31)

Fixed an issue where valid LINK config and credential parameters were not supported for both reading from and writing to a datasource.

Fixed an issue where the number of rows affected with SELECT INTO object storage was erroneously reported as 0 rows.

Fixed an issue where small tables use an inappropriately small sample size by setting a lower bound. This mostly affects reference tables.

Fixed a potential crash that could occur when LOAD DATA is used without a database context.

Pipeline state is now shown consistently across primary and child nodes.

Fixed an issue with the SET clause of the CREATE PIPELINE statement: now it is possible to use type options like NULL/NOT NULL/COLLATE... with :>/!:> typecast operators.

Added a new engine variable pipelines_cdc_java_heap_size to specify the JVM heap size limit for CDC-in pipelines.

Fixed an issue with JSON_SET_JSON used in UDFs.

Fixed a potential issue related to hash join spilling.

Reduced blocking in query compilation after evicting many (10K+) plans in the plancache.

Added three new fields to MV_SYSINFO_DISK:

• READ_OPERATIONS_CUMULATIVE_PER_DEVICE: Number of read operations performed by the device since start up.

• WRITE_OPERATIONS_CUMULATIVE_PER_DEVICE: Number of write operations performed by the device since start up.

• DEVICE_NAME: Name of the device to which the values in read_operations_cumulative_per_device and write_operations_cumulative_per_device are associated.

Disabled order_by_self_join rewrite when an ORDER BY contains an indeterminate function.

Disabled group-by on encoded data when there is an aggregate on full-text match.

Fixed a potential security issue with users created without a password.

Fixed some cases where APPROX_COUNT_DISTINCT_ACCUMULATE erroneously included nulls in the count.

Fixed an issue preventing correct ingestion from MongoDB® collections with dot symbols.

Fixed an issue in CDC pipelines that could lead to Java Out Of Memory errors.

Improved performance during snapshotting for CDC-in pipelines.

Changed the SingleStore Helios workspace default and range for the pipelines_cdc_row_emit_delay_us engine variable. Throttling default value is set to 1. The supported range is from 0 to 1000000.

Addressed some performance issues that occur when performing large sets of security operations (creating a lot of groups/users/roles, etc.) via the new privilege_caches_update_mode engine variable.

This variable can be used to temporarily disable updating privilege caches while performing security operations such as: granting/revoking permissions to/from users, granting/revoking permissions to/from roles, adding/deleting roles to/from groups, adding/deleting users to/from groups, role deletion, group deletion. This can result in a performance gain.

IT IS IMPORTANT that the privilege cache updates be reenabled (value set back to always) once the administration work is finished.

To use this variable:

1. Set the value to never.

2. Perform the operations.

3. Set the value back to always.

Fixed a crash caused when AS WASM/WITH WIT is used in a CREATE AGGREGATE statement that (1) doesn't have HANDLE as the state type, and (2) doesn't supply the SERIALIZE and DESERIALIZE callbacks.

Fixed an issue where error messages were not generated when corrupt blob was encountered during json encoding read/write.

Added additional node metrics to the /cluster-metrics endpoint of the memsql_exporter.

Reverted the ability to use SSL keys with a password in the HTTP API.

Fixed an upgrade issue where some databases could temporarily become unrecoverable if snapshots were skipped during a pre-upgrade on a recently attached unlimited database.

Fixed an issue preventing nodes from attaching during upgrade.

Added ability to use SSL keys with a password in the HTTP API.

Added support for simple multi-column update with sub-query.

Added resource pool metrics to the /cluster-metrics endpoint of the memsql_exporter.

Added ability to infer CSV data with text boolean values.

Fixed background pipelines not respecting max concurrency limit in the resource pool. Please note that this change will affect previously created pipelines using a constrained resource pool, including the error state if MAX_QUEUE_DEPTH is exceeded.

Fixed an issue with two-phase commit that could lead to loss of atomicity on databases restored from 8.1 backups.

Fixed an issue with the transaction log not being downgradable to previous 8.1 patch releases.

Fixed an issue where two-phase commit would not work correctly on disaster recovery failovers.

Improved the performance of mv_replication_status for clusters with large DR databases.

Improved blob cache sync performance when there is no running query.

Added support for flipping join order for FULL OUTER JOIN operations.

Fixed an issue where unlimited storage databases stored on Amazon S3 could run out of connections under intense loads.

Fixed a bug where leaf failover and ATTACH LEAF would copy extra partitions.

Fixed an issue where the rebalance done by ATTACH LEAF was unstable with respect to REBALANCE ALL DATABASES.

Fixed an issue where an incorrect result is produced when the engine variable query_parallelism is set with flexible_parallelism. query_parallelism is deprecated and query_parallelism_per_leaf_core should be used instead.

Removed an unexpected warning related to the engine variable query_parallelism (which is deprecated) when a query contains an ORDER BY clause with an IN list filter that matches the table's shard key.

The START TRANSACTION command is no longer allowed from Data API unless it is inside a stored procedure.

Now redirecting the AWS-GO-SDK log to a file instead of writing to stdout.

Fixed a bug where an aggregator result table hits a lockdown when sql_select_limit is set.

Added two engine variables: max_expression_query_limit which sets a limit on the number of expressions within an entire query and max_expression_item_limit which sets a limit on the number of expressions within a query item. Both can be set to a range between 100 and the maximum unsigned INT value. Setting these engine variables to the maximum unsigned INT value disables both features.

Fixed an issue where a crash occurs where the engine improperly rewrites queries with a UNION in an EXCEPT clause.

Fixed several issues causing slow compilation for queries over wide tables.

Added two engine variables, jwks_username_field and jwks_require_audience to add flexibility and improve security.

Added support for materializing CTEs without recomputing them when the query contains UNION, UNION ALL, and other SET operations. To enable the feature, set the engine variable allow_materialize_cte_with_union to TRUE. The default value for this engine variable is FALSE for version 8.1.19 and earlier.

Fixed a memory leak issue in the memsql_exporter process.

Enhanced the performance of DDL statements for role manipulation.

The SHOW COLUMNAR MERGE STATUS command now outputs status for tables with empty sort keys.

The following commands now respect non-default columnstore_table_lock_threshold values: INSERT ... SELECT ... ON DUPLICATE UPDATE, REPLACE ... SELECT, and REPLACE ... LOAD.

Fixed an issue where VECTOR_MUL was returning incorrect results on shard tables.

Fixed an issue where memsql_exporter was generating too much "pipeline_error" data.

Fixed an issue with the Kerberos cache for HDFS pipelines.

Improved memory consumption in json decoding.

Fixed an issue where LIMIT and OFFSET after a window function with no PARTITION BY clause were returning incorrect information.

The WARM BLOB CACHE FOR INDEX command can now accept index names that conflict with reserved identifiers (such as PRIMARY, etc.).

Added support for the REGEXP_MATCH() function. This function returns a JSON array of matching substring(s) within the first match of a regular expression pattern to a string.

Improved performance of multi-part GCS backups.

Introduced a new global engine variable json_document_max_leaves which limits the number of JSON key paths inferred within a segment. The default value is 10000.

Fixed an issue where BACKUP or RESTORE of an existing backup from GCS fails on SingleStore versions newer than 8.1.6.

Fixed an issue where BACKUP DATABASE WITH INIT would fail under out-of-memory conditions.

Fixed a potential crash in NFS backup when encountering an IO error.

Added support for multiple uncorrelated IN-subselects in more query shapes.

SKIP PARSER ERRORS is now supported for Kafka. Additionally, a new related engine variable, pipelines_parse_errors_threshold, has been added.

Fixed an issue with the incremental restore of an unlimited database that would fail if the restore was larger than the disk.

SingleStore automatically rewrites A=B OR (A IS NULL AND B IS NULL) to null safe equal (A<=>B) to enable hash joins.

Added support for hash joins on null-accepting expressions in the ON condition of outer joins.

Fixed an issue with significant memory reduction from spilling for hash join queries with variable length strings (varchar, text, etc.) involved.

Introduced a new global variable, dr_min_connection_timeout_ms, which allows users to adjust the minimum timeout period in Disaster Recovery (DR) replication.

Fixed a bug that could cause Amazon S3 pipelines to stop loading data.

Added support for Control Group v2 (cgroup v2).

Fixed an issue where a large spike in the query memory consumption on a any SingleStore node could cause replicas on the same node to become unrecoverable.

Fixed a pipeline wrong state issue caused by an error in a table with a computed column.

Fixed a potential issue where REBALANCE PARTITION would not stabilize to a partition placement on a read replica's workspace.

Fixed a potential crash in some edge cases when using Parquet pipelines.

Fixed an issue with upgrade steps not running in some edge cases. A logging change was required, making the log format incompatible with earlier patch releases.

Fixed a crash that may occur when using SELECT … FOR UPDATE … LIMIT <n> in a multi-statement transaction when two_phase_commit is ON.

Fixed a bug where the permissions do not clear for Data Manipulation Language (DML) queries and then leak to subsequent Data Definition Language (DDL) queries.

Fixed a bug where the mv_disk_usage table would show incorrect results for the plancache directory.

Default values for BLOB/TEXT and JSON columns are allowed, as well as NULL and empty strings. Fixed a bug where utf8mb4 characters were not allowed inside default values for CHAR/VARCHAR columns.

CREATE TABLE table_1(col_1 JSON DEFAULT {'amt': 10});

CREATE TABLE table_2(col_1 BLOB DEFAULT ('xyz'));

CREATE TABLE table_2(col_1 longtext DEFAULT '{...}');

Fixed a potential issue where changing a user password would not change the connection pool password in the Data API.

Reverted the performance improvements for backups to GCS (Google Cloud Storage).

Bugfix: Fixed a crash that may occur when a function calls more than one external function.

In the following example get_embedding() is an external function:

SELECT DOT_PRODUCT(JSON_ARRAY_PACK(get_embedding('house')), 
JSON_ARRAY_PACK(get_embedding('car'))

Added an opt-in optimization to Kerberos for HDFS pipelines to reduce the amount of requests.

Added a LimitNICE value into the service file. This change affects installations where SingleStore Helios is running as a service.

Fixed a JSON formatting issue for the PARTITION_UNRECOVERABLE event in MV_EVENTS details column.

Fixed the dependency on PIPES_AS_CONCAT sql_mode inside user defined functions. The sql_mode state is now stored when a user defined function is created and used whenever the function is executed.

Fixed a bug in memsql_exporter that may cause it to stop accepting HTTP requests.

Added support for opaque OAUTHBEARER tokens in Kafka Pipelines.

Added support for ROW_COUNT information function within views.

SingleStore does not support using the environment variables to initialize OpenSSL 3.

Added two engine variables (workload_management_enable_large_memory_classification and workload_management_available_leaf_memory_ratio) to help tune workload management to better support queuing with high memory queries.

Fixed a bug where a pipeline would fail with error code 2789. The error occurred when the pipeline's "cursor offset" was below its "earliest offset".

Fixed a bug where a HashJoin on a materialized CTE gets executed as a NestedLoopJoin in some query shapes causing slow join performance.

Fixed the SPLIT string function that was not detecting the correct argument type when used inside a table-valued function (TVF) or a user-defined scalar-valued function (UDF).

Improved the accuracy of the blob_fetch_network_time statistic in query profiles.

Added metrics to memsql_exporter that show the breakdown of disk usage by SingleStore Helios. Also, added metrics to memsql_exporter that show unlimited storage utilization statistics.

Fixed a bug with the blob_fetch_network_time statistic in query profiles.

Fixed a performance bug about queue size when flexible parallelism is enabled. Overall query performance is increased.

Fixed an issue where, when parsing a table with many secondary keys, an incorrect name was used to refer to table's the primary key.

Enhanced the on-disk plancache functionality by shrinking the plancache when disk space gets low and the on-disk plancache is using at least 25% of available disk space.

Fixed a bug where unlimited storage garbage collection could occur before a partition could recover from that version.

Fixed a vulnerability in memsql_exporter by updating Go Prometheus client to 1.15.1.

Added a metric to the memsql_exporter that shows whether there are unavailable partitions in any database.

PAM (Pluggable Authentication Module) users are now allowed to start and configure the memsql_exporter process.

Added support for disk spilling for LEFT OUTER JOIN query shapes.

Added the max_execution_time engine variable. It is unused and setting this variable has no effect. It exists so certain MySQL-compatible apps that have this variable set will not fail when connected to SingleStore Helios.

Added mv_disk_usage and mv_data_disk_usage information schema tables that report the breakdown of disk utilization by SingleStore Helios.

Fixed an issue on sample tables that can be created with different collations on different partitions.

Fixed an issue where JSON computed column matching incorrectly triggers a JSON function.

Introduced the 8.1 data_conversion_compatibility_level which provides additional out-of-range checks for the TIMESTAMP data type.

Fixed a rare case where the query optimizer re-wrote a query into a non-equivalent query which produced more result rows.

Improved the performance of backups to GCS (Google Cloud Storage). GCS backups are not using multi-part uploads.

Fixed unlimited storage S3 multipart uploads to properly retry on 200 responses which contain an embedded "SlowDown" error, instead of failing immediately.

Fixed an issue where memory accumulates over time if reshuffle or repartition operators are executed for many unique query shapes.

Fixed an issue with crashes that occur when SSL is enabled on universal storage databases.

The FLUSH EXTRACTOR POOLS command now runs on all nodes in a cluster when run on an aggregator.

Improved the memsqlctl management tool's describe-node property variables command to display global variables instead of session variables.

Disabled semi-join operator reduction optimization.

Fixed an issue where the query optimizer could choose incorrectly between using the HashGroupBy or the StreamingGroupBy operators.

Added more information about blob files that need to be downloaded from unlimited storage to the blob cache when running PROFILE.

Fixed rare issue with sync durability and unlimited storage that could cause log file corruption in the blob storage.

Fixed an issue with optimizing queries containing no-operation predicates such as 1=1.

Improved the performance of a left join of a reference table with a sharded table by pushing the reference table clauses to the leaves. The engine variable disable_reference_table_leftjoin_where_pushdown must be set to "OFF" to enable this operation.

Now allowing child aggregator root users to be dropped even if the sync_permissionengine variable is enabled.

Removed the restrictions on the names of JWT users. Customers may now create users with names that look like UUIDs and emails.

Fixed a bug with error handling that produced spam messages.

Backups taken from the 8.1.3 release (and subsequent 8.1 releases) are no longer restorable into the previous 8.1 releases (8.1.1 and 8.1.2).

Removed the EXECUTE permission requirements for Kai internal UDFs.

Changed the system information built-ins to use the utf8_general_ci collation for the collation_server value.