VMware Tanzu Greenplum 6.15 Release Notes
VMware Tanzu Greenplum 6.15 Release Notes
This document contains pertinent release information about VMware Tanzu Greenplum Database 6.15 releases. For previous versions of the release notes for Greenplum Database, go to VMware Tanzu Greenplum Database Documentation. For information about Greenplum Database end of life, see VMware Tanzu Greenplum Database end of life policy.
VMware Tanzu Greenplum 6 software is available for download from the VMware Tanzu Greenplum page on VMware Tanzu Network.
VMware Tanzu Greenplum 6 is based on the open source Greenplum Database project code.
Release 6.15.0
Release Date: 2021-3-11
VMware Tanzu Greenplum 6.15.0 is a minor release that includes changed features and resolves several issues.
Features
Greenplum Database 6.15.0 includes these new and changed features:
- gprecoverseg now rebalances segments whose hosts are reachable even if there are other segments whose hosts are not; for segments on unreachable hosts, gprecoverseg now emits a warning message.
- Greenplum Streaming Server (GPSS) version 1.5.2 is included, which
introduces bug fixes. Refer to the
GPSS Release Notes
for more information on release content and to access the GPSS documentation.
Note: If you have previously used GPSS in your Greenplum 6.x installation, you are required to perform upgrade actions as described in Upgrading the Streaming Server.
- The analyzedb utility has a new --skip_orca_root_stats option. When this option is specified, analyzedb will not update root partition statistics. This option should be used only if GPORCA is disabled.
Resolved Issues
VMware Tanzu Greenplum 6.15.0 resolves these issues:
- 31267 - Server
- Fixed error resource group wait queue is corrupted (resgroup.c:3502) that caused a PANIC on Greenplum Master.
- 31262 - Server
- Resolved an issue with inconsistencies in returned results when using the grouping function.
- 31260/30895 - External Tables
- Fixed issue with Web External Tables when escape='OFF'.
- 31249 - Query Optimizer
- Certain queries that selected random rows in a partitioned table, using functions like random() or timeofday(), would cause host PANIC. This issue has been resolved.
- 31244 - analyzedb
- Added --skip_orca_root_stats option, which prevents analyzedb from updating root partition statistics.
- 31228 - Data Flow
- dblink includes function dblink_connect_no_auth that skips authentication checks.
- 31223 - Query Optimizer
- Fixed optimizer issue with cardinality estimation for point queries on CDOUBLE types, such as timestamp.
- 31220 - Data Flow
- Resolved an issue in which gpfdist reads from external tables were resulting in "No route to host" errors.
- 31210 - Interconnect
- Resolves a high memory usage issue with proxy background worker processes when gp_interconnect_type = proxy, and the pause/resume flow control process causes a busy receiver to cache or duplicate packets while waiting for the backend to consume them. Greenplum Database now uses a more active flow control mechanism to control packet buffering and transmission.
- 31191 - Server
- Fixed planner issue of queries crashing with FailedAssertion error due to planner issue.
- 31055 - Server
- Prohibits the execution of queries with set returning functions in WHERE clause, which caused segment panic. Greenplum now generates an error similar to: set-returning functions are not allowed in WHERE clause.
- 176693327 - Cluster Management
- gpinitsystem now treats equivalent locales as equivalent (for example, en_US.UTF-8 is now treated the same as en_US.utf8).
- 176521407 - Cluster Management
- Because gprecoverseg now reports progress on both incremental and full segment recovery, there is no longer any need to call gpstate -m to determine recovery progress.
Upgrading from Greenplum 6.x to Greenplum 6.15
See Upgrading from an Earlier Greenplum 6 Release to upgrade your existing Greenplum 6.x software to Greenplum 6.15.
Deprecated Features
Deprecated features will be removed in a future major release of Greenplum Database. VMware Tanzu Greenplum 6.x deprecates:
- The gpsys1 utility.
- The analzyedb option --skip_root_stats (deprecated
since 6.2).
If the option is specified, a warning is issued stating that the option will be ignored.
- The server configuration parameter gp_statistics_use_fkeys (deprecated since 6.2).
- The server configuration parameter gp_ignore_error_table (deprecated
since 6.0).
To avoid a Greenplum Database syntax error, set the value of this parameter to true when you run applications that execute CREATE EXTERNAL TABLE or COPY commands that include the now removed Greenplum Database 4.3.x INTO ERROR TABLE clause.
- Specifying => as an operator name in the CREATE OPERATOR command (deprecated since 6.0).
- The Greenplum external table C API (deprecated since 6.0).
Any developers using this API are encouraged to use the new Foreign Data Wrapper API in its place.
- Commas placed between a SUBPARTITION TEMPLATE clause and its
corresponding SUBPARTITION BY clause, and between consecutive
SUBPARTITION BY clauses in a CREATE TABLE command
(deprecated since 6.0).
Using this undocumented syntax will generate a deprecation warning message.
- The timestamp format YYYYMMDDHH24MISS (deprecated since 6.0).
This format could not be parsed unambiguously in previous Greenplum Database releases, and is not supported in PostgreSQL 9.4.
- The createlang and droplang utilities (deprecated since 6.0).
- The pg_resqueue_status system view (deprecated since 6.0).
Use the gp_toolkit.gp_resqueue_status view instead.
- The GLOBAL and LOCAL modifiers when creating a
temporary table with the CREATE TABLE and CREATE TABLE
AS commands (deprecated since 6.0).
These keywords are present for SQL standard compatibility, but have no effect in Greenplum Database.
- Using WITH OIDS or oids=TRUE to assign an OID system column when creating or altering a table (deprecated since 6.0).
- Allowing superusers to specify the SQL_ASCII encoding regardless of the
locale settings (deprecated since 6.0).
This choice may result in misbehavior of character-string functions when data that is not encoding-compatible with the locale is stored in the database.
- The @@@ text search operator (deprecated since 6.0).
This operator is currently a synonym for the @@ operator.
- The unparenthesized syntax for option lists in the VACUUM command
(deprecated since 6.0).
This syntax requires that the options to the command be specified in a specific order.
- The plain pgbouncer authentication type (auth_type = plain) (deprecated since 4.x).
Migrating Data to Greenplum 6
Greenplum 6 supports direct upgrades, using gpupgrade, from Greenplum 5.x releases to Greenplum 6.x. For more information, see the gpupgrade documentation. See also Migrating Data from Greenplum 4.3 or 5 for guidelines and considerations for migrating existing Greenplum data to Greenplum 6, using standard backup and restore procedures.
Known Issues and Limitations
VMware Tanzu Greenplum 6 has these limitations:
- Upgrading a Greenplum Database 4 release to VMware Tanzu Greenplum 6 is not supported. Upgrading a Greenplum Database 5.x release to VMware Tanzu Greenplum 6 is supported via gpupgrade. For more information, see the gpupgrade documentation.
- MADlib, GPText, and PostGIS are not yet provided for installation on Ubuntu systems.
- Greenplum for Kubernetes is not yet provided with this release.
The following table lists key known issues in VMware Tanzu Greenplum 6.x.
Issue | Category | Description |
---|---|---|
31010 | Query Optimizer | A view created in Greenplum Database 5.28.3 or older that
specified an external table in the FROM clause,
and that was migrated to Greenplum Database 6.x, always falls
back to the Postgres Planner when queried.
Workaround: If you migrated a view from Greenplum Database 5.28.3 or earlier, and the view specified an external table in the FROM clause, you must drop and recreate the view in Greenplum 6.x to ensure that the Query Optimizer is exercised when you query the view. |
N/A | Backup/Restore | Restoring the Greenplum Database backup for a table fails in
Greenplum 6 versions earlier than version 6.10 when a replicated
table has an inheritance relationship to/from another table that
was assigned via an ALTER TABLE ... INHERIT
statement after table creation.
Workaround: Use the following SQL commands to determine
if Greenplum Database includes any replicated tables that
inherit from a parent table, or if there are replicated tables
that are inherited by a child table:
SELECT inhrelid::regclass FROM pg_inherits, gp_distribution_policy dp WHERE inhrelid=dp.localoid AND dp.policytype='r'; SELECT inhparent::regclass FROM pg_inherits, gp_distribution_policy dp WHERE inhparent=dp.localoid AND dp.policytype='r'; If these queries return any tables, you may choose to run gprestore with the -–on-error-continue flag to not fail the entire restore when this issue is hit. Or, you can specify the list of tables returned by the queries to the -–exclude-table-file option to skip those tables during restore. You must recreate and repopulate the affected tables after restore. |
N/A | Spark Connector | This version of Greenplum is not compatible with Greenplum-Spark Connector versions earlier than version 1.7.0, due to a change in how Greenplum handles distributed transaction IDs. |
N/A | PXF | Starting in 6.x, Greenplum does not bundle cURL and instead
loads the system-provided library. PXF requires cURL version 7.29.0
or newer. The officially-supported cURL for the CentOS 6.x and Red
Hat Enterprise Linux 6.x operating systems is version 7.19.*. Greenplum Database 6
does not support running PXF on CentOS 6.x or RHEL 6.x due to this limitation.
Workaround: Upgrade the operating system of your Greenplum Database 6 hosts to CentOS 7+ or RHEL 7+, which provides a cURL version suitable to run PXF. |
29703 | Loading Data from External Tables | Due to limitations in the Greenplum Database external table framework,
Greenplum Database cannot log the following types of errors that it encounters while
loading data:
Workaround: Clean the input data before loading it into Greenplum Database. |
30594 | Resource Management | Resource queue-related statistics may be inaccurate in certain cases. VMware recommends that you use the resource group resource management scheme that is available in Greenplum 6. |
30522 | Logging | Greenplum Database may write a FATAL message to the standby master or mirror log stating that the database system is in recovery mode when the instance is synchronizing with the master and Greenplum attempts to contact it before the operation completes. Ignore these messages and use gpstate -f output to determine if the standby successfully synchronized with the Greenplum master; the command returns Sync state: sync if it is synchronized. |
30537 | Postgres Planner | The Postgres Planner generates a very large query plan that causes out of
memory issues for the following type of CTE (common table expression) query: the
WITH clause of the CTE contains a partitioned table with a large
number partitions, and the WITH reference is used in a subquery
that joins another partitioned table. Workaround: If possible, use the GPORCA query optimizer. With the server configuration parameter optimizer=on, Greenplum Database attempts to use GPORCA for query planning and optimization when possible and falls back to the Postgres Planner when GPORCA cannot be used. Also, the specified type of query might require a long time to complete. |
170824967 | gpfdists | For Greenplum Database 6.x, a command that accesses an external table that uses the gpfdists protocol fails if the external table does not use an IP address when specifying a host system in the LOCATION clause of the external table definition. |
n/a | Materialized Views | By default, certain gp_toolkit views do not display data for materialized views. If you want to include this information in gp_toolkit view output, you must redefine a gp_toolkit internal view as described in Including Data for Materialized Views. |
168957894 | PXF | The PXF Hive Connector does not support using the Hive*
profiles to access Hive transactional tables. Workaround: Use the PXF JDBC Connector to access Hive. |
168548176 | gpbackup | When using gpbackup to back up a Greenplum Database 5.7.1 or earlier 5.x release with resource groups enabled, gpbackup returns a column not found error for t6.value AS memoryauditor. |
164791118 | PL/R | PL/R cannot be installed using the deprecated createlang
utility, and displays the
error:createlang: language installation failed: ERROR: no schema has been selected to create inWorkaround: Use CREATE EXTENSION to install PL/R, as described in the documentation. |
N/A | Greenplum Client/Load Tools on Windows | The Greenplum Database client and load tools on Windows have not been tested with Active Directory Kerberos authentication. |
Differences Compared to Open Source Greenplum Database
- Product packaging and installation script
- Support for QuickLZ compression. QuickLZ compression is not provided in the open source version of Greenplum Database due to licensing restrictions.
- Support for data connectors:
- Greenplum-Spark Connector
- Greenplum-Informatica Connector
- Greenplum-Kafka Integration
- Greenplum Streaming Server
- Data Direct ODBC/JDBC Drivers
- gpcopy utility for copying or migrating objects between Greenplum systems
- Support for managing Greenplum Database using VMware Tanzu Greenplum Command Center
- Support for full text search and text analysis using VMware Tanzu GPText
- Greenplum backup plugin for DD Boost
- Backup/restore storage plugin API