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[MDEV-10570] Add Flashback support

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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:
This commit is contained in:
Monty
2017-01-20 15:33:28 +02:00
parent b9631b4633
commit d75d8631ed
12 changed files with 1377 additions and 55 deletions
Download Patch File Download Diff File Expand all files Collapse all files

251
client/mysqlbinlog.cc
View File

@@ -66,6 +66,10 @@ Rpl_filter *binlog_filter= 0;
/* Needed for Rpl_filter */
CHARSET_INFO* system_charset_info= &my_charset_utf8_general_ci;
/* Needed for Flashback */
DYNAMIC_ARRAY binlog_events; // Storing the events output string
String stop_event_string; // Storing the STOP_EVENT output string
char server_version[SERVER_VERSION_LENGTH];
ulong server_id = 0;
@@ -89,7 +93,7 @@ static const char *load_groups[]=
static void error(const char *format, ...) ATTRIBUTE_FORMAT(printf, 1, 2);
static void warning(const char *format, ...) ATTRIBUTE_FORMAT(printf, 1, 2);
static bool one_database=0, to_last_remote_log= 0, disable_log_bin= 0;
static bool one_database=0, one_table=0, to_last_remote_log= 0, disable_log_bin= 0;
static bool opt_hexdump= 0, opt_version= 0;
const char *base64_output_mode_names[]=
{"NEVER", "AUTO", "ALWAYS", "UNSPEC", "DECODE-ROWS", NullS};
@@ -99,6 +103,7 @@ TYPELIB base64_output_mode_typelib=
static enum_base64_output_mode opt_base64_output_mode= BASE64_OUTPUT_UNSPEC;
static char *opt_base64_output_mode_str= NullS;
static char* database= 0;
static char* table= 0;
static my_bool force_opt= 0, short_form= 0, remote_opt= 0;
static my_bool debug_info_flag, debug_check_flag;
static my_bool force_if_open_opt= 1;
@@ -132,6 +137,12 @@ static MYSQL* mysql = NULL;
static const char* dirname_for_local_load= 0;
static bool opt_skip_annotate_row_events= 0;
static my_bool opt_flashback;
#ifdef WHEN_FLASHBACK_REVIEW_READY
static my_bool opt_flashback_review;
static char *flashback_review_dbname, *flashback_review_tablename;
#endif
/**
Pointer to the Format_description_log_event of the currently active binlog.
@@ -790,6 +801,23 @@ print_skip_replication_statement(PRINT_EVENT_INFO *pinfo, const Log_event *ev)
pinfo->skip_replication= cur_val;
}
/**
Indicates whether the given table should be filtered out,
according to the --table=X option.
@param log_tblname Name of table.
@return nonzero if the table with the given name should be
filtered out, 0 otherwise.
*/
static bool shall_skip_table(const char *log_tblname)
{
return one_table &&
(log_tblname != NULL) &&
strcmp(log_tblname, table);
}
/**
Prints the given event in base64 format.
@@ -952,6 +980,12 @@ Exit_status process_event(PRINT_EVENT_INFO *print_event_info, Log_event *ev,
Exit_status retval= OK_CONTINUE;
IO_CACHE *const head= &print_event_info->head_cache;
/* Bypass flashback settings to event */
ev->is_flashback= opt_flashback;
#ifdef WHEN_FLASHBACK_REVIEW_READY
ev->need_flashback_review= opt_flashback_review;
#endif
/*
Format events are not concerned by --offset and such, we always need to
read them to be able to process the wanted events.
@@ -988,7 +1022,7 @@ Exit_status process_event(PRINT_EVENT_INFO *print_event_info, Log_event *ev,
retval= OK_STOP;
goto end;
}
if (!short_form)
if (!short_form && !opt_flashback)
fprintf(result_file, "# at %s\n",llstr(pos,ll_buff));
if (!opt_hexdump)
@@ -1214,12 +1248,128 @@ Exit_status process_event(PRINT_EVENT_INFO *print_event_info, Log_event *ev,
case TABLE_MAP_EVENT:
{
Table_map_log_event *map= ((Table_map_log_event *)ev);
if (shall_skip_database(map->get_db_name()))
if (shall_skip_database(map->get_db_name()) ||
shall_skip_table(map->get_table_name()))
{
print_event_info->m_table_map_ignored.set_table(map->get_table_id(), map);
destroy_evt= FALSE;
goto end;
}
#ifdef WHEN_FLASHBACK_REVIEW_READY
/* Create review table for Flashback */
if (opt_flashback_review)
{
// Check if the table was already created?
Table_map_log_event *exist_table;
exist_table= print_event_info->m_table_map.get_table(map->get_table_id());
if (!exist_table)
{
MYSQL *conn;
MYSQL_RES *res;
MYSQL_ROW row;
char tmp_sql[8096];
int tmp_sql_offset;
conn = mysql_init(NULL);
if (!mysql_real_connect(conn, host, user, pass,
map->get_db_name(), port, sock, 0))
{
fprintf(stderr, "%s\n", mysql_error(conn));
exit(1);
}
if (mysql_query(conn, "SET group_concat_max_len=10000;"))
{
fprintf(stderr, "%s\n", mysql_error(conn));
exit(1);
}
memset(tmp_sql, 0, sizeof(tmp_sql));
sprintf(tmp_sql, " "
"SELECT Group_concat(cols) "
"FROM (SELECT 'op_type char(1)' cols "
" UNION ALL "
" SELECT Concat('`', column_name, '_old` ', column_type, ' ', "
" IF(character_set_name IS NOT NULL, "
" Concat('character set ', character_set_name, ' '), ' '), "
" IF(collation_name IS NOT NULL, "
" Concat('collate ', collation_name, ' '), ' ')) cols "
" FROM information_schema.columns "
" WHERE table_schema = '%s' "
" AND table_name = '%s' "
" UNION ALL "
" SELECT Concat('`', column_name, '_new` ', column_type, ' ', "
" IF(character_set_name IS NOT NULL, "
" Concat('character set ', character_set_name, ' '), ' '), "
" IF(collation_name IS NOT NULL, "
" Concat('collate ', collation_name, ' '), ' ')) cols "
" FROM information_schema.columns "
" WHERE table_schema = '%s' "
" AND table_name = '%s') tmp;",
map->get_db_name(), map->get_table_name(),
map->get_db_name(), map->get_table_name());
if (mysql_query(conn, tmp_sql))
{
fprintf(stderr, "%s\n", mysql_error(conn));
exit(1);
}
res = mysql_use_result(conn);
if ((row = mysql_fetch_row(res)) != NULL) // only one row
{
if (flashback_review_dbname)
{
ev->set_flashback_review_dbname(flashback_review_dbname);
}
else
{
ev->set_flashback_review_dbname(map->get_db_name());
}
if (flashback_review_tablename)
{
ev->set_flashback_review_tablename(flashback_review_tablename);
}
else
{
memset(tmp_sql, 0, sizeof(tmp_sql));
sprintf(tmp_sql, "__%s", map->get_table_name());
ev->set_flashback_review_tablename(tmp_sql);
}
memset(tmp_sql, 0, sizeof(tmp_sql));
tmp_sql_offset= sprintf(tmp_sql, "CREATE TABLE IF NOT EXISTS");
tmp_sql_offset+= sprintf(tmp_sql + tmp_sql_offset, " `%s`.`%s` (%s) %s",
ev->get_flashback_review_dbname(),
ev->get_flashback_review_tablename(),
row[0],
print_event_info->delimiter);
}
fprintf(result_file, "%s\n", tmp_sql);
mysql_free_result(res);
mysql_close(conn);
}
else
{
char tmp_str[128];
if (flashback_review_dbname)
ev->set_flashback_review_dbname(flashback_review_dbname);
else
ev->set_flashback_review_dbname(map->get_db_name());
if (flashback_review_tablename)
ev->set_flashback_review_tablename(flashback_review_tablename);
else
{
memset(tmp_str, 0, sizeof(tmp_str));
sprintf(tmp_str, "__%s", map->get_table_name());
ev->set_flashback_review_tablename(tmp_str);
}
}
}
#endif
/*
The Table map is to be printed, so it's just the time when we may
print the kept Annotate event (if there is any).
@@ -1294,6 +1444,38 @@ end:
*/
if (ev)
{
/* Holding event output if needed */
if (!ev->output_buf.is_empty())
{
LEX_STRING tmp_str;
tmp_str.length= ev->output_buf.length();
tmp_str.str= ev->output_buf.release();
if (opt_flashback)
{
if (ev_type == STOP_EVENT)
stop_event_string.reset(tmp_str.str, tmp_str.length, tmp_str.length,
&my_charset_bin);
else
{
if (push_dynamic(&binlog_events, (uchar *) &tmp_str))
{
error("Out of memory: can't allocate memory to store the flashback events.");
exit(1);
}
}
}
else
{
my_fwrite(result_file, (const uchar *) tmp_str.str, tmp_str.length,
MYF(MY_NABP));
my_free(tmp_str.str);
}
}
if (remote_opt)
ev->temp_buf= 0;
if (destroy_evt) /* destroy it later if not set (ignored table map) */
delete ev;
}
@@ -1352,6 +1534,13 @@ static struct my_option my_options[] =
"already have. NOTE: you will need a SUPER privilege to use this option.",
&disable_log_bin, &disable_log_bin, 0, GET_BOOL,
NO_ARG, 0, 0, 0, 0, 0, 0},
{"flashback", 'B', "Flashback feature can rollback you committed data to a special time point.",
#ifdef WHEN_FLASHBACK_REVIEW_READY
"before Flashback feature writing a row, original row can insert to review-dbname.review-tablename,"
"and mysqlbinlog will login mysql by user(-u) and password(-p) and host(-h).",
#endif
&opt_flashback, &opt_flashback, 0, GET_BOOL, NO_ARG, 0, 0, 0, 0,
0, 0},
{"force-if-open", 'F', "Force if binlog was not closed properly.",
&force_if_open_opt, &force_if_open_opt, 0, GET_BOOL, NO_ARG,
1, 0, 0, 0, 0, 0},
@@ -1395,6 +1584,19 @@ static struct my_option my_options[] =
"prefix for the file names.",
&result_file_name, &result_file_name, 0, GET_STR, REQUIRED_ARG,
0, 0, 0, 0, 0, 0},
#ifdef WHEN_FLASHBACK_REVIEW_READY
{"review", opt_flashback_review, "Print review sql in output file.",
&opt_flashback_review, &opt_flashback_review, 0, GET_BOOL, NO_ARG, 0, 0, 0, 0,
0, 0},
{"review-dbname", opt_flashback_flashback_review_dbname,
"Writing flashback original row data into this db",
&flashback_review_dbname, &flashback_review_dbname,
0, GET_STR_ALLOC, REQUIRED_ARG, 0, 0, 0, 0, 0, 0},
{"review-tablename", opt_flashback_flashback_review_tablename,
"Writing flashback original row data into this table",
&flashback_review_tablename, &flashback_review_tablename,
0, GET_STR_ALLOC, REQUIRED_ARG, 0, 0, 0, 0, 0, 0},
#endif
{"server-id", 0,
"Extract only binlog entries created by the server having the given id.",
&server_id, &server_id, 0, GET_ULONG,
@@ -1458,6 +1660,9 @@ static struct my_option my_options[] =
&stop_position, &stop_position, 0, GET_ULL,
REQUIRED_ARG, (longlong)(~(my_off_t)0), BIN_LOG_HEADER_SIZE,
(ulonglong)(~(my_off_t)0), 0, 0, 0},
{"table", 'T', "List entries for just this table (local log only).",
&table, &table, 0, GET_STR_ALLOC, REQUIRED_ARG,
0, 0, 0, 0, 0, 0},
{"to-last-log", 't', "Requires -R. Will not stop at the end of the \
requested binlog but rather continue printing until the end of the last \
binlog of the MySQL server. If you send the output to the same MySQL server, \
@@ -1567,6 +1772,7 @@ static void cleanup()
{
my_free(pass);
my_free(database);
my_free(table);
my_free(host);
my_free(user);
my_free(const_cast<char*>(dirname_for_local_load));
@@ -1637,6 +1843,9 @@ get_one_option(int optid, const struct my_option *opt __attribute__((unused)),
break;
#endif
#include <sslopt-case.h>
case 'B':
opt_flashback= 1;
break;
case 'd':
one_database = 1;
break;
@@ -1658,10 +1867,18 @@ get_one_option(int optid, const struct my_option *opt __attribute__((unused)),
case 'R':
remote_opt= 1;
break;
case 'T':
one_table= 1;
break;
case OPT_MYSQL_PROTOCOL:
opt_protocol= find_type_or_exit(argument, &sql_protocol_typelib,
opt->name);
break;
#ifdef WHEN_FLASHBACK_REVIEW_READY
case opt_flashback_review:
opt_flashback_review= 1;
break;
#endif
case OPT_START_DATETIME:
start_datetime= convert_str_to_timestamp(start_datetime_str);
break;
@@ -1862,7 +2079,7 @@ static Exit_status dump_log_entries(const char* logname)
dump_local_log_entries(&print_event_info, logname));
/* Set delimiter back to semicolon */
if (!opt_raw_mode)
if (!opt_raw_mode && !opt_flashback)
fprintf(result_file, "DELIMITER ;\n");
strmov(print_event_info.delimiter, ";");
return rc;
@@ -2660,6 +2877,9 @@ int main(int argc, char** argv)
DBUG_ENTER("main");
DBUG_PROCESS(argv[0]);
(void) my_init_dynamic_array(&binlog_events, sizeof(LEX_STRING), 1024, 1024,
MYF(0));
my_init_time(); // for time functions
tzset(); // set tzname
@@ -2795,6 +3015,29 @@ int main(int argc, char** argv)
start_position= BIN_LOG_HEADER_SIZE;
}
/*
If enable flashback, need to print the events from the end to the
beginning
*/
if (opt_flashback)
{
for (uint i= binlog_events.elements; i > 0; --i)
{
LEX_STRING *event_str= dynamic_element(&binlog_events, i - 1,
LEX_STRING*);
fprintf(result_file, "%s", event_str->str);
my_free(event_str->str);
}
fprintf(result_file, "COMMIT\n/*!*/;\n");
}
delete_dynamic(&binlog_events);
/* Set delimiter back to semicolon */
if (!stop_event_string.is_empty())
fprintf(result_file, "%s", stop_event_string.ptr());
if (!opt_raw_mode && opt_flashback)
fprintf(result_file, "DELIMITER ;\n");
if (!opt_raw_mode)
{
/*