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• LAST_TRANSACTION_ID 

The ID of the most recent transaction that was written to this log type with this compression type. 

• LAST_TRANSACTION_COMPRESSED_BYTES 

The total number of bytes that were compressed and then written to the log for the most recent transaction, counted after compression. 

• LAST_TRANSACTION_UNCOMPRESSED_BYTES 

The total number of bytes before compression for the most recent transaction. 

• LAST_TRANSACTION_TIMESTAMP 

The timestamp when the most recent transaction was written to the log. 

The binary_log_transaction_compression_stats  table has no indexes. 

TRUNCATE TABLE  is permitted for the binary_log_transaction_compression_stats  table. 

## 27.12.12 Performance Schema NDB Cluster Tables 

The following table shows all Performance Schema tables relating to the NDBCLUSTER  storage engine. 

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Beginning with NDB 8.0.16, automatic synchronization in NDB  attempts to detect and synchronize automatically all mismatches in metadata between the NDB Cluster’s internal dictionary and the MySQL Server’s datadictionary. This is done by default in the background at regular intervals as determined by the ndb_metadata_check_interval  system variable, unless disabled using ndb_metadata_check or overridden by setting ndb_metadata_sync . Prior to NDB 8.0.21, the only information readily accessible to users about this process was in the form of logging messages and object counts available (beginning with NDB 8.0.18) as the status variables Ndb_metadata_detected_count , Ndb_metadata_synced_count , and Ndb_metadata_excluded_count  (prior to NDB 8.0.22, this variable was named Ndb_metadata_blacklist_size ). Beginning with NDB 8.0.21, more detailed information about the current state of automatic synchronization is exposed by a MySQL server acting as an SQL node in an NDB Cluster in these two Performance Schema tables: 

• ndb_sync_pending_objects : Displays information about NDB  database objects for which mismatches have been detected between the NDB  dictionary and the MySQL data dictionary. When attempting to synchronize such objects, NDB  removes the object from the queue awaiting synchronization, and from this table, and tries to reconcile the mismatch. If synchronization of the object fails due to a temporary error, it is picked up and added back to the queue (and to this table) the next time NDB  performs mismatch detection; if the attempts fails due a permanent error, the object is added to the ndb_sync_excluded_objects  table. 

• ndb_sync_excluded_objects : Shows information about NDB  database objects for which automatic synchronization has failed due to permanent errors resulting from mismatches which cannot be 

