Pivotal Greenplum 6.8.1 resolves these issues:

30664 - Query Optimizer

For a complex CTAS query that has implicit casts in the project list, GPORCA may generate a plan with duplicate eliminating motions, to ensure correctness. However, if a duplicate eliminating motion is performed under the hash operation of a Hash Join, an implicit cast operation creates an additional column that causes memtuple binding issues in the executor. To address this problem, GPORCA now generates a modified plan that prunes the output of any duplicate eliminating motions before sending the output to the hash operation.

30684 - Query Optimizer

GPORCA returned incorrect results for some queries when the query's select list contains a window function and the window function contains a correlated subquery or an outer reference. Now the query falls back to the Postgres planner.

30615 - Query Optimizer

GPORCA query performance degraded when compared with Greenplum 5 for some queries that perform joins using an equality predicate and the equality predicate contains a function, for example coalesce(tbl1.a, '999999') = coalesce(tbl2.a, '999999'). The performance issue was caused by inaccurate cardinality estimates. GPORCA cardinality estimation has been improved for the specified type of query.

172732495, 9953 - query execution

Greenplum Database generated a PANIC when executing a query that executes multiple user-defined functions and more than one of the functions is defined with the EXECUTE ON INITPLAN attribute. This issue is resolved.

172098556 - psql

Resolved a problem where the psql client \dm command did not display materialized views.

172094194, 9837 - gprecoverseg

In some cases when recovering segment instances using the gprecoverseg utility with the -i <recover_config_file> option to specify details about failed segments to recover, the utility changed some segment instance dbid values in the Greenplum system configuration. This issue is resolved.

Greenplum Database 6.8.0 includes these new and changed features:

• Greenplum Streaming Server (GPSS) version 1.3.6 is included, which introduces many new and changed features and bug fixes since the last GPSS version installed in Greenplum 6.x (1.3.1). 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 gpinitsystem input configuration file specified with the -I option supports an additional format to specify hosts. The QD_PRIMARY_ARRAY, PRIMARY_ARRAY, and MIRROR_ARRAY host parameters may now be specified using either of the following formats:

  host~port~data_directory/seg_prefix<segment_id>~dbid~content_id

  hostname~address~port~data_directory/seg_prefix<segment_id>~dbid~content_id

  The first format, which is the pre-existing format, sets both the hostname and address columns of the gp_segment_configuration catalog table to the value in the host field. The second format sets the hostname and address columns of the gp_segment_configuration catalog table to the values in the respective hostname and address fields. See

• PXF version 5.12.0 is included, which introduces new and changed features and bug fixes. See PXF Version 5.12.0 below.
• PL/Container version 2.1.2 is included, which introduces the following new features:
  • Support for R version 3.6.3.
  • A new --use_local_copy option to the plcontainer add-image command that you can use to install the specified image only on the local host.
• Greenplum Database 6.8 adds support for Moving a Query to a Different Resource Group.
• Greenplum Database 6.8 includes a new metrics collector extension that is compatible with Greenplum Command Center 6.2 and above. If you are using Command Center 6.0 or 6.1 you must download and install Command Center 6.2 after you install Greenplum Database 6.8.

Pivotal Greenplum 6.8.0 resolves these issues:

329, 30602 - PXF

PXF did not correctly read a partitioned Hive table when the external table specified a Hive* profile and the external table and Hive table had a differing number of columns. This issue is resolved. PXF now supports column projection for the Hive* profiles and correctly handles this situation.

30611 - Query Optimizer

When falling back to the Postgres planner, GPORCA incorrectly logged messages that were internal messages. This made the log file difficult to read and caused bloat in the file. This issue is resolved. GPORCA message logging has been improved and the internal messages are no longer sent to the log files.

30585 - Locking

Resolved a problem that could corrupt resource queue locks, and potentially other types of locks, in shared memory. This problem could cause errors such as lock lock_name on object object_identifier is already held.

30557 - DDL

When performing a data reorganization with the ALTER TABLE command on a leaf partition of a partitioned table that did not change the distribution policy, Greenplum Database returned the error ERROR: can't set the distribution policy. This type of redistribution is allowed in Greenplum 5. Now Greenplum allows data reorganization on a leaf partition if the distribution policy is not changed.

30289 - Query Optimizer

When GPORCA performed dynamic partition elimination for some queries against partitioned tables that perform joins, GPORCA was not using the correct statistics. This caused a performance degradation when compared with Greenplum 5. GPORCA has improved how statistics are computed tor the specified type of query.

172854840 - Interconnect

In some cases, a query that executes a stable function that contains an SQL statement might hang because the query dispatcher (QD) did not correctly manage the execution of the function and the dispatching of the query plan. This issue is resolved.

172832212 - Interconnect

In some cases, communication between a query dispatcher (QD) and a query executor (QE) on different segments was slow when the Greenplum interconnect type is set to the TCP networking protocol for Greenplum Database interconnect traffic. Now the communication between a QD and a QE is more efficient.

172615233 - Query Optimizer

For text data types, the GPORCA the cardinality estimation algorithm has been improved for equality comparisons. For example, when a query contains an IN clause that contains text elements.

172576000 - COPY

If data format errors occurred while copying data into a partitioned table with a COPY FROM command in single row error isolation mode, Greenplum Database might crash when a query executor (QE) did not handle the data format error correctly. This issue is resolved.

30487 - Utility Commands

On a Greenplum Database 6 system with FIPS enabled, Greenplum utility commands such as gpinitsystem returned the error "ERROR:root:code for hash md5 was not found." This issue is resolved.

30484 - Utility Commands

When initializing a Greenplum Database system with gpinitsystem, the primary segments were erroneously named using DNS resolvable external hostnames instead of the internal interconnect interface hostnames. At the same time, the segment mirrors were correctly named. This issue is now resolved.

See Upgrading from an Earlier Greenplum 6 Release to upgrade your existing Greenplum 6.x software to Greenplum 6.8.0.