Changes in MySQL NDB Cluster 7.6.11 (5.7.27-ndb-7.6.11) (2019-07-23, General Availability)

MySQL NDB Cluster 7.6.11 is a new release of NDB 7.6, based on MySQL Server 5.7 and including features in version 7.6 of the NDB storage engine, as well as fixing recently discovered bugs in previous NDB Cluster releases.

Obtaining NDB Cluster 7.6.  NDB Cluster 7.6 source code and binaries can be obtained from https://dev.mysql.com/downloads/cluster/.

For an overview of changes made in NDB Cluster 7.6, see What is New in NDB Cluster 7.6.

This release also incorporates all bug fixes and changes made in previous NDB Cluster releases, as well as all bug fixes and feature changes which were added in mainline MySQL 5.7 through MySQL 5.7.27 (see Changes in MySQL 5.7.27 (2019-07-22, General Availability)).

• Functionality Added or Changed

• Bugs Fixed

Functionality Added or Changed

• Building with CMake3 is now supported by the compile-cluster script included in the NDB source distribution. (WL #12303)

Bugs Fixed

• Important Change: The dependency of ndb_restore on the NDBT library, which is used for internal testing only, has been removed. This means that the program no longer prints NDBT_ProgramExit: ... when terminating. Applications that depend upon this behavior should be updated to reflect this change when upgrading to this release. (WL #13117)

• NDB Replication: NDB did not handle binary logging of virtual generated columns of type BLOB correctly. Now such columns are always regarded as having zero length.

• A pushed join with ORDER BY did not always return the rows of the result in the specified order. This could occur when the optimizer used an ordered index to provide the ordering and the index used a column from the table that served as the root of the pushed join. (Bug #29860378)

• The requestInfo fields for the long and short forms of the LQHKEYREQ signal had different definitions; bits used for the key length in the short version were reused for flags in the long version, since the key length is implicit in the section length of the long version of the signal but it was possible for long LQHKEYREQ signals to contain a keylength in these same bits, which could be misinterpreted by the receiving local query handler, potentially leading to errors. Checks have now been implemented to make sure that this no longer happens. (Bug #29820838)

• Lack of SharedGlobalMemory was incorrectly reported as lack of undo buffer memory, even though the cluster used no disk data tables. (Bug #29806771)

  References: This issue is a regression of: Bug #92125, Bug #28537319.

• Long TCKEYREQ signals did not always use the expected format when invoked from TCINDXREQ processing. (Bug #29772731)

• Improved error message printed when the maximum offset for a FIXED column is exceeded. (Bug #29714670)

• Data nodes could fail due to an assert in the DBTC block under certain circumstances in resource-constrained environments. (Bug #29528188)

• An upgrade to NDB 7.6.9 or later from an earlier version could not be completed successfully if the redo log was filled to more than 25% of capacity. (Bug #29506844)

• When the DBSPJ block called the internal function lookup_resume() to schedule a previously enqueued operation, it used a correlation ID which could have been produced from its immediate ancestor in the execution order, and not its parent in the query tree as assumed. This could happen during execution of a SELECT STRAIGHT_JOIN query.

  Now NDB checks whether the execution ancestor is different from the query tree parent, and if not, performs a lookup of the query tree parent, and the parent's correlation ID is enqueued to be executed later. (Bug #29501263)

• When a new master took over, sending a MASTER_LCP_REQ signal and executing MASTER_LCPCONF from participating nodes, it expected that they had not completed the current local checkpoint under the previous master, which need not be true. (Bug #29487340, Bug #29601546)

• When restoring TINYBLOB columns, ndb_restore now treats them as having the BINARY character set. (Bug #29486538)

• Restoration of epochs by ndb_restore failed due to temporary redo errors. Now ndb_restore retries epoch updates when such errors occur. (Bug #29466089)

• ndb_restore --restore-epoch incorrectly reported the stop GCP as 1 less than the actual position. (Bug #29343655)

• Added support which was missing in ndb_restore for conversions between the following sets of types:

  • BLOB and BINARY or VARBINARY columns

  • TEXT and BLOB columns

  • BLOB columns with unequal lengths

  • BINARY and VARBINARY columns with unequal lengths

  (Bug #28074988)

• Restore points in backups created with the SNAPSHOTSTART option (see Using The NDB Cluster Management Client to Create a Backup) were not always consistent with epoch boundaries. (Bug #27566346)

  References: See also: Bug #27497461.