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Commit a4ff3120 authored by aelkin@mysql.com's avatar aelkin@mysql.com
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Bug#17263 temporary tables and replication 

  Backporting a changeset made for 5.0. Comments from there:

  The fix refines the algorithm of generating DROPs for binlog.
  Temp tables with common pseudo_thread_id are clustered into one query.
  Consequently one replication event per pseudo_thread_id is generated.
parent 50e8e58c
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Showing with 162 additions and 41 deletions
mysql-test/r/rpl_temporary.result
View file @ a4ff3120
......@@ -89,3 +89,17 @@ f
7
drop table t1,t2;
create temporary table t3 (f int);
set @session.pseudo_thread_id=100;
create temporary table t101 (id int);
create temporary table t102 (id int);
set @session.pseudo_thread_id=200;
create temporary table t201 (id int);
create temporary table `#not_user_table_prefixed_with_hash_sign_no_harm` (id int);
set @con1_id=connection_id();
kill @con1_id;
create table t1(f int);
insert into t1 values (1);
select * from t1 /* must be 1 */;
f
1
drop table t1;
mysql-test/t/rpl_temporary.test
View file @ a4ff3120
......@@ -128,6 +128,32 @@ drop table t1,t2;
create temporary table t3 (f int);
sync_with_master;
# The server will now close done
#
# BUG#17263 incorrect generation DROP temp tables
# Temporary tables of connection are dropped in batches
# where a batch correspond to pseudo_thread_id
# value was set up at the moment of temp table creation
#
connection con1;
set @session.pseudo_thread_id=100;
create temporary table t101 (id int);
create temporary table t102 (id int);
set @session.pseudo_thread_id=200;
create temporary table t201 (id int);
create temporary table `#not_user_table_prefixed_with_hash_sign_no_harm` (id int);
set @con1_id=connection_id();
kill @con1_id;
#now do something to show that slave is ok after DROP temp tables
connection master;
create table t1(f int);
insert into t1 values (1);
sync_slave_with_master;
#connection slave;
select * from t1 /* must be 1 */;
connection master;
drop table t1;
# End of 4.1 tests
sql/sql_base.cc
View file @ a4ff3120
......@@ -483,13 +483,23 @@ void close_temporary(TABLE *table,bool delete_table)
DBUG_VOID_RETURN;
}
/* close_temporary_tables' internal */
static inline uint tmpkeyval(THD *thd, TABLE *table)
{
return uint4korr(table->table_cache_key + table->key_length -
sizeof(thd->variables.pseudo_thread_id));
}
/* Creates one DROP TEMPORARY TABLE binlog event for each pseudo-thread */
void close_temporary_tables(THD *thd)
{
TABLE *table,*next;
char *query, *end;
uint query_buf_size;
bool found_user_tables = 0;
TABLE *next,
*prev_table /* prev link is not maintained in TABLE's double-linked list */,
*table;
char *query= (gptr) 0, *end;
uint query_buf_size, max_names_len;
bool found_user_tables;
if (!thd->temporary_tables)
return;
......@@ -497,51 +507,122 @@ void close_temporary_tables(THD *thd)
LINT_INIT(end);
query_buf_size= 50; // Enough for DROP ... TABLE IF EXISTS
for (table=thd->temporary_tables ; table ; table=table->next)
/*
insertion sort of temp tables by pseudo_thread_id to build ordered list
of sublists of equal pseudo_thread_id
*/
for (prev_table= thd->temporary_tables,
table= prev_table->next,
found_user_tables= (prev_table->table_name[0] != '#');
table;
prev_table= table, table= table->next)
{
TABLE *prev_sorted /* same as for prev_table */,
*sorted;
/*
We are going to add 4 ` around the db/table names, so 1 does not look
enough; indeed it is enough, because table->key_length is greater (by 8,
because of server_id and thread_id) than db||table.
table not created directly by the user is moved to the tail.
Fixme/todo: nothing (I checked the manual) prevents user to create temp
with `#'
*/
query_buf_size+= table->key_length+1;
if ((query = alloc_root(thd->mem_root, query_buf_size)))
if (table->real_name[0] == '#')
continue;
else
{
found_user_tables = 1;
}
for (prev_sorted= NULL, sorted= thd->temporary_tables; sorted != table;
prev_sorted= sorted, sorted= sorted->next)
{
if (sorted->real_name[0] == '#' || tmpkeyval(thd, sorted) > tmpkeyval(thd, table))
{
/* move into the sorted part of the list from the unsorted */
prev_table->next= table->next;
table->next= sorted;
if (prev_sorted)
{
prev_sorted->next= table;
}
else
{
thd->temporary_tables= table;
}
table= prev_table;
break;
}
}
}
/*
calc query_buf_size as max per sublists, one sublist per pseudo thread id.
Also stop at first occurence of `#'-named table that starts
all implicitly created temp tables
*/
for (max_names_len= 0, table=thd->temporary_tables;
table && table->real_name[0] != '#';
table=table->next)
{
uint tmp_names_len;
for (tmp_names_len= table->key_length + 1;
table->next && table->real_name[0] != '#' &&
tmpkeyval(thd, table) == tmpkeyval(thd, table->next);
table=table->next)
{
/*
We are going to add 4 ` around the db/table names, so 1 might not look
enough; indeed it is enough, because table->key_length is greater (by 8,
because of server_id and thread_id) than db||table.
*/
tmp_names_len += table->next->key_length + 1;
}
if (tmp_names_len > max_names_len) max_names_len= tmp_names_len;
}
/* allocate */
if (found_user_tables && mysql_bin_log.is_open() &&
(query = alloc_root(thd->mem_root, query_buf_size+= max_names_len)))
// Better add "if exists", in case a RESET MASTER has been done
end=strmov(query, "DROP /*!40005 TEMPORARY */ TABLE IF EXISTS ");
end= strmov(query, "DROP /*!40005 TEMPORARY */ TABLE IF EXISTS ");
for (table=thd->temporary_tables ; table ; table=next)
/* scan sorted tmps to generate sequence of DROP */
for (table=thd->temporary_tables; table; table= next)
{
if (query) // we might be out of memory, but this is not fatal
if (query // we might be out of memory, but this is not fatal
&& table->real_name[0] != '#')
{
// skip temporary tables not created directly by the user
if (table->real_name[0] != '#')
found_user_tables = 1;
char *end_cur;
/* Set pseudo_thread_id to be that of the processed table */
thd->variables.pseudo_thread_id= tmpkeyval(thd, table);
/* Loop forward through all tables within the sublist of
common pseudo_thread_id to create single DROP query */
for (end_cur= end;
table && table->real_name[0] != '#' &&
tmpkeyval(thd, table) == thd->variables.pseudo_thread_id;
table= next)
{
end_cur= strxmov(end_cur, "`", table->table_cache_key, "`.`",
table->real_name, "`,", NullS);
next= table->next;
close_temporary(table, 1);
}
thd->clear_error();
/* The -1 is to remove last ',' */
Query_log_event qinfo(thd, query, (ulong)(end_cur - query) - 1, 0, FALSE);
/*
Here we assume table_cache_key always starts
with \0 terminated db name
Imagine the thread had created a temp table, then was doing a SELECT, and
the SELECT was killed. Then it's not clever to mark the statement above as
"killed", because it's not really a statement updating data, and there
are 99.99% chances it will succeed on slave.
If a real update (one updating a persistent table) was killed on the
master, then this real update will be logged with error_code=killed,
rightfully causing the slave to stop.
*/
end = strxmov(end,"`",table->table_cache_key,"`.`",
table->real_name,"`,", NullS);
qinfo.error_code= 0;
mysql_bin_log.write(&qinfo);
}
else
{
next= table->next;
close_temporary(table, 1);
}
next=table->next;
close_temporary(table);
}
if (query && found_user_tables && mysql_bin_log.is_open())
{
/* The -1 is to remove last ',' */
thd->clear_error();
Query_log_event qinfo(thd, query, (ulong)(end-query)-1, 0, FALSE);
/*
Imagine the thread had created a temp table, then was doing a SELECT, and
the SELECT was killed. Then it's not clever to mark the statement above as
"killed", because it's not really a statement updating data, and there
are 99.99% chances it will succeed on slave.
If a real update (one updating a persistent table) was killed on the
master, then this real update will be logged with error_code=killed,
rightfully causing the slave to stop.
*/
qinfo.error_code= 0;
mysql_bin_log.write(&qinfo);
}
thd->temporary_tables=0;
}
......
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