Important Change: When ndb_restore was run without
--rebuild-indexeson a table having a unique index, it was possible for rows to be restored in an order that resulted in duplicate values, causing it to fail with duplicate key errors. Running
ndb_restoreon such a table now requires using at least one of these options; failing to do so now results in an error. (Bug #57782, Bug #11764893)
References: See also: Bug #22329365, Bug #22345748.
NDB Cluster APIs: While executing
dropEvent(), if the coordinator
DBDICTfailed after the subscription manager (
SUMAblock) had removed all subscriptions but before the coordinator had deleted the event from the system table, the dropped event remained in the table, causing any subsequent drop or create event with the same name to fail with
NDBerror 1419 Subscription already dropped or error 746 Event name already exists. This occurred even when calling
dropEvent()with a nonzero force argument.
Now in such cases, error 1419 is ignored, and
DBDICTdeletes the event from the table. (Bug #21554676)
NDB Cluster APIs: The internal value representing the latest global checkpoint was not always updated when a completed epoch of event buffers was inserted into the event queue. This caused subsequent calls to
pollEvents2()to fail when trying to obtain the correct GCI for the events available in the event buffers. This could also result in later calls to
nextEvent2()seeing events that had not yet been discovered. (Bug #78129, Bug #21651536)
Backup block states were reported incorrectly during backups. (Bug #21360188)
References: See also: Bug #20204854, Bug #21372136.
When a data node is known to have been alive by other nodes in the cluster at a given global checkpoint, but its
sysfilereports a lower GCI, the higher GCI is used to determine which global checkpoint the data node can recreate. This caused problems when the data node being started had a clean file system (GCI = 0), or when it was more than more global checkpoint behind the other nodes.
Now in such cases a higher GCI known by other nodes is used only when it is at most one GCI ahead. (Bug #19633824)
References: See also: Bug #20334650, Bug #21899993. This issue is a regression of: Bug #29167.
When restoring a specific database or databases with the
--exclude-databasesoption, ndb_restore attempted to apply foreign keys on tables in databases which were not among those being restored. (Bug #18560951)
After restoring the database schema from backup using ndb_restore, auto-discovery of restored tables in transactions having multiple statements did not work correctly, resulting in Deadlock found when trying to get lock; try restarting transaction errors.
This issue was encountered both in the mysql client, as well as when such transactions were executed by application programs using Connector/J and possibly other MySQL APIs.
Prior to upgrading, this issue can be worked around by executing
SELECT TABLE_NAME, TABLE_SCHEMA FROM INFORMATION_SCHEMA.TABLES WHERE ENGINE = 'NDBCLUSTER'on all SQL nodes following the restore operation, before executing any other statements. (Bug #18075170)
Trying to create an
NDBtable with a composite foreign key referencing a composite primary key of the parent table failed when one of the columns in the composite foreign key was the table's primary key and in addition this column also had a unique key. (Bug #78150, Bug #21664899)
When attempting to enable index statistics, creation of the required system tables, events and event subscriptions often fails when multiple mysqld processes using index statistics are started concurrently in conjunction with starting, restarting, or stopping the cluster, or with node failure handling. This is normally recoverable, since the affected mysqld process or processes can (and do) retry these operations shortly thereafter. For this reason, such failures are no longer logged as warnings, but merely as informational events. (Bug #77760, Bug #21462846)
Adding a unique key to an
NDBtable failed when the table already had a foreign key. Prior to upgrading, you can work around this issue by creating the unique key first, then adding the foreign key afterwards, using a separate
ALTER TABLEstatement. (Bug #77457, Bug #20309828)