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==== Description ====
Flashback can rollback the instances/databases/tables to an old snapshot.
It's implement on Server-Level by full image format binary logs (--binlog-row-image=FULL), so it supports all engines.
Currently, it’s a feature inside mysqlbinlog tool (with --flashback arguments).
Because the flashback binlog events will store in the memory, you should check if there is enough memory in your machine.
==== New Arguments to mysqlbinlog ====
--flashback (-B)
It will let mysqlbinlog to work on FLASHBACK mode.
==== New Arguments to mysqld ====
--flashback
Setup the server to use flashback. This enables binary log in row mode
and will enable extra logging for DDL's needed by flashback feature
==== Example ====
I have a table "t" in database "test", we can compare the output with "--flashback" and without.
#client/mysqlbinlog /data/mysqldata_10.0/binlog/mysql-bin.000001 -vv -d test -T t --start-datetime="2013-03-27 14:54:00" > /tmp/1.sql
#client/mysqlbinlog /data/mysqldata_10.0/binlog/mysql-bin.000001 -vv -d test -T t --start-datetime="2013-03-27 14:54:00" -B > /tmp/2.sql
Then, importing the output flashback file (/tmp/2.log), it can flashback your database/table to the special time (--start-datetime).
And if you know the exact postion, "--start-postion" is also works, mysqlbinlog will output the flashback logs that can flashback to "--start-postion" position.
==== Implement ====
1. As we know, if binlog_format is ROW (binlog-row-image=FULL in 10.1 and later), all columns value are store in the row event, so we can get the data before mis-operation.
2. Just do following things:
2.1 Change Event Type, INSERT->DELETE, DELETE->INSERT.
For example:
INSERT INTO t VALUES (...) ---> DELETE FROM t WHERE ...
DELETE FROM t ... ---> INSERT INTO t VALUES (...)
2.2 For Update_Event, swapping the SET part and WHERE part.
For example:
UPDATE t SET cols1 = vals1 WHERE cols2 = vals2
--->
UPDATE t SET cols2 = vals2 WHERE cols1 = vals1
2.3 For Multi-Rows Event, reverse the rows sequence, from the last row to the first row.
For example:
DELETE FROM t WHERE id=1; DELETE FROM t WHERE id=2; ...; DELETE FROM t WHERE id=n;
--->
DELETE FROM t WHERE id=n; ...; DELETE FROM t WHERE id=2; DELETE FROM t WHERE id=1;
2.4 Output those events from the last one to the first one which mis-operation happened.
For example:
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|---|---|---|
| .. | ||
| binlog_base64_flag.test | ||
| binlog_bug23533.test | ||
| binlog_bug36391-master.opt | ||
| binlog_bug36391.test | ||
| binlog_checkpoint.test | ||
| binlog_checksum.test | ||
| binlog_commit_wait.test | ||
| binlog_database.test | ||
| binlog_delete_and_flush_index-master.opt | ||
| binlog_delete_and_flush_index.test | ||
| binlog_dmls_on_tmp_tables_readonly.test | ||
| binlog_drop_if_exists.test | ||
| binlog_format_switch_in_tmp_table.test | ||
| binlog_grant.test | ||
| binlog_implicit_commit.test | ||
| binlog_incident.test | ||
| binlog_index-master.opt | ||
| binlog_index.test | ||
| binlog_innodb.test | ||
| binlog_innodb_row.test | ||
| binlog_ioerr.test | ||
| binlog_killed.test | ||
| binlog_killed_simulate-master.opt | ||
| binlog_killed_simulate.test | ||
| binlog_max_extension.test | ||
| binlog_mdev342-master.opt | ||
| binlog_mdev342.test | ||
| binlog_mdev717.test | ||
| binlog_mixed_cache_stat.test | ||
| binlog_mixed_load_data.test | ||
| binlog_mysqlbinlog-cp932-master.opt | ||
| binlog_mysqlbinlog-cp932.test | ||
| binlog_mysqlbinlog2-master.opt | ||
| binlog_mysqlbinlog2.test | ||
| binlog_mysqlbinlog_base64.test | ||
| binlog_mysqlbinlog_row-master.opt | ||
| binlog_mysqlbinlog_row.test | ||
| binlog_mysqlbinlog_row_innodb-master.opt | ||
| binlog_mysqlbinlog_row_innodb.test | ||
| binlog_mysqlbinlog_row_myisam-master.opt | ||
| binlog_mysqlbinlog_row_myisam.test | ||
| binlog_mysqlbinlog_row_trans-master.opt | ||
| binlog_mysqlbinlog_row_trans.test | ||
| binlog_old_versions.test | ||
| binlog_query_filter_rules-master.opt | ||
| binlog_query_filter_rules.test | ||
| binlog_row_annotate-master.opt | ||
| binlog_row_annotate.test | ||
| binlog_row_binlog-master.opt | ||
| binlog_row_binlog.test | ||
| binlog_row_cache_stat.test | ||
| binlog_row_ctype_cp932.test | ||
| binlog_row_ctype_ucs.test | ||
| binlog_row_drop_tbl.test | ||
| binlog_row_drop_tmp_tbl.test | ||
| binlog_row_innodb_stat-master.opt | ||
| binlog_row_insert_select.test | ||
| binlog_row_mix_innodb_myisam-master.opt | ||
| binlog_row_mix_innodb_myisam.test | ||
| binlog_row_mysqlbinlog_db_filter.test | ||
| binlog_row_mysqlbinlog_options-master.opt | ||
| binlog_row_mysqlbinlog_options.test | ||
| binlog_row_mysqlbinlog_verbose.test | ||
| binlog_server_id.test | ||
| binlog_sf.test | ||
| binlog_spurious_ddl_errors-master.opt | ||
| binlog_spurious_ddl_errors.test | ||
| binlog_sql_mode.test | ||
| binlog_start_comment.test | ||
| binlog_statement_insert_delayed.test | ||
| binlog_stm_binlog-master.opt | ||
| binlog_stm_binlog.test | ||
| binlog_stm_blackhole.test | ||
| binlog_stm_cache_stat.test | ||
| binlog_stm_ctype_cp932.test | ||
| binlog_stm_ctype_ucs.test | ||
| binlog_stm_do_db-master.opt | ||
| binlog_stm_do_db.test | ||
| binlog_stm_drop_tbl.test | ||
| binlog_stm_drop_tmp_tbl.test | ||
| binlog_stm_innodb_stat-master.opt | ||
| binlog_stm_insert_select.test | ||
| binlog_stm_mix_innodb_myisam-master.opt | ||
| binlog_stm_mix_innodb_myisam.test | ||
| binlog_stm_ps.test | ||
| binlog_stm_row.test | ||
| binlog_stm_unsafe_warning-master.opt | ||
| binlog_stm_unsafe_warning.test | ||
| binlog_stm_user_variables.test | ||
| binlog_switch_inside_trans.test | ||
| binlog_tmp_table.test | ||
| binlog_trigger.test | ||
| binlog_truncate_innodb-master.opt | ||
| binlog_truncate_innodb.test | ||
| binlog_truncate_kill.test | ||
| binlog_truncate_myisam.test | ||
| binlog_unsafe-master.opt | ||
| binlog_unsafe.test | ||
| binlog_variables_log_bin-master.opt | ||
| binlog_variables_log_bin.test | ||
| binlog_variables_log_bin_index-master.opt | ||
| binlog_variables_log_bin_index.test | ||
| binlog_variables_relay_log-master.opt | ||
| binlog_variables_relay_log.test | ||
| binlog_variables_relay_log_index-master.opt | ||
| binlog_variables_relay_log_index.test | ||
| binlog_write_error.test | ||
| binlog_xa_recover-master.opt | ||
| binlog_xa_recover.test | ||
| flashback-master.opt | ||
| flashback.test | ||
| load_data_stm_view.test | ||
| temptable_uservar_disconnect-7938.test | ||