pt-query-digest --output json includes query examples as of v2.2.3. Some people might not want this because it exposes real data. New option, --output json-anon, has been implemented. This option will provide the same data without query examples. It’s “anonymous” in the sense that there’s no identifying data; nothing more than schema and table structs can be inferred from fingerprints.
When using drop swap with pt-online-schema-change there is some production impact. This impact can be measured because tool outputs the current timestamp on lines for operations that may take awhile. Before this feature was implemented this information wasn’t available.
修复的Bugs： Bugs Fixed:
pt-table-checksum would fail if variable explicit_defaults_for_timestamp was enabled in MySQL 5.6. Bug fixed #1163735.
Trying to assign 0 to any variable by using --set-vars option would cause “Invalid --set-vars value” message. Bug fixed #1182856.
Fixed the typo in the pt-online-schema-change code that could lead to a tool crash when copying the rows. Bug fixed #1188264
pt-table-checksum was using the first non-unique index instead of the one with the highest cardinality due to a sorting bug. Bug fixed #1199591