Commit a4251d6f authored by Sergei Golubchik's avatar Sergei Golubchik

MDEV-15391 Server crashes in JOIN::fix_all_splittings_in_plan or Assertion...

MDEV-15391 Server crashes in JOIN::fix_all_splittings_in_plan or Assertion `join->best_read < double(1.79...e+308L)' failed

vers_setup_conds() used to AND all conditions on row_start/row_end
columns and store it either in the WHERE clause or in the ON
clause for some table. In some cases this caused ON clause
to have conditions for tables that aren't part of that ON's join.

Fixed to put a table's condition always in the ON clause of the
corresponding table.

Removed unnecessary ... `OR row_end IS NULL` clause, it's not needed
in the ON clause.

Simplified handling on PS and SP.
parent 1a86fc5f
......@@ -211,12 +211,12 @@ id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t2 ALL NULL NULL NULL NULL 3 100.00 Using where
1 SIMPLE t1 ALL NULL NULL NULL NULL 5 100.00 Using where; Using join buffer (flat, BNL join)
Query A:
Note 1003 select `test`.`t1`.`x` AS `x`,`test`.`t1`.`y` AS `y1`,`test`.`t2`.`x` AS `x2`,`test`.`t2`.`y` AS `y2` from `test`.`t1` FOR SYSTEM_TIME ALL join `test`.`t2` FOR SYSTEM_TIME ALL where `test`.`t1`.`x` = `test`.`t2`.`x` and `test`.`t1`.`row_end` > <cache>(current_timestamp(6)) and `test`.`t1`.`row_start` <= <cache>(current_timestamp(6)) and `test`.`t2`.`row_end` > <cache>(current_timestamp(6)) and `test`.`t2`.`row_start` <= <cache>(current_timestamp(6))
Note 1003 select `test`.`t1`.`x` AS `x`,`test`.`t1`.`y` AS `y1`,`test`.`t2`.`x` AS `x2`,`test`.`t2`.`y` AS `y2` from `test`.`t1` FOR SYSTEM_TIME ALL join `test`.`t2` FOR SYSTEM_TIME ALL where `test`.`t1`.`x` = `test`.`t2`.`x` and `test`.`t2`.`row_end` > <cache>(current_timestamp(6)) and `test`.`t2`.`row_start` <= <cache>(current_timestamp(6)) and `test`.`t1`.`row_end` > <cache>(current_timestamp(6)) and `test`.`t1`.`row_start` <= <cache>(current_timestamp(6))
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t2 ALL NULL NULL NULL NULL 3 100.00 Using where
1 SIMPLE t1 ALL NULL NULL NULL NULL 5 100.00 Using where; Using join buffer (flat, BNL join)
Query B:
Note 1003 select `test`.`t1`.`x` AS `x`,`test`.`t1`.`y` AS `y1`,`test`.`t2`.`x` AS `x2`,`test`.`t2`.`y` AS `y2` from `test`.`t1` FOR SYSTEM_TIME ALL join `test`.`t2` FOR SYSTEM_TIME ALL where `test`.`t1`.`x` = `test`.`t2`.`x` and `test`.`t1`.`row_end` > <cache>(current_timestamp(6)) and `test`.`t1`.`row_start` <= <cache>(current_timestamp(6)) and `test`.`t2`.`row_end` > <cache>(current_timestamp(6)) and `test`.`t2`.`row_start` <= <cache>(current_timestamp(6))
Note 1003 select `test`.`t1`.`x` AS `x`,`test`.`t1`.`y` AS `y1`,`test`.`t2`.`x` AS `x2`,`test`.`t2`.`y` AS `y2` from `test`.`t1` FOR SYSTEM_TIME ALL join `test`.`t2` FOR SYSTEM_TIME ALL where `test`.`t1`.`x` = `test`.`t2`.`x` and `test`.`t2`.`row_end` > <cache>(current_timestamp(6)) and `test`.`t2`.`row_start` <= <cache>(current_timestamp(6)) and `test`.`t1`.`row_end` > <cache>(current_timestamp(6)) and `test`.`t1`.`row_start` <= <cache>(current_timestamp(6))
Fine result: queries A and B are equal.
## LEFT JOIN: t1, t2 versioned
select * from (
......
......@@ -153,21 +153,21 @@ id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t2 ALL NULL NULL NULL NULL 3 100.00 Using where
1 SIMPLE t1 ALL NULL NULL NULL NULL 5 100.00 Using where; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select `test`.`t1`.`x` AS `IJ2_x1`,`test`.`t1`.`y` AS `y1`,`test`.`t2`.`x` AS `x2`,`test`.`t2`.`y` AS `y2` from `test`.`t1` FOR SYSTEM_TIME ALL join `test`.`t2` FOR SYSTEM_TIME ALL where `test`.`t1`.`x` = `test`.`t2`.`x` and `test`.`t1`.`row_end` > @`t0` and `test`.`t1`.`row_start` <= @`t0` and `test`.`t2`.`row_end` > @`t0` and `test`.`t2`.`row_start` <= @`t0`
Note 1003 select `test`.`t1`.`x` AS `IJ2_x1`,`test`.`t1`.`y` AS `y1`,`test`.`t2`.`x` AS `x2`,`test`.`t2`.`y` AS `y2` from `test`.`t1` FOR SYSTEM_TIME ALL join `test`.`t2` FOR SYSTEM_TIME ALL where `test`.`t1`.`x` = `test`.`t2`.`x` and `test`.`t2`.`row_end` > @`t0` and `test`.`t2`.`row_start` <= @`t0` and `test`.`t1`.`row_end` > @`t0` and `test`.`t1`.`row_start` <= @`t0`
explain extended select * from (select t1.x as LJ2_x1, t1.y as y1, t2.x as x2, t2.y as y2 from t1 left join t2 on t1.x = t2.x)
for system_time as of timestamp @t0 as t;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 5 100.00
1 SIMPLE t1 ALL NULL NULL NULL NULL 5 100.00 Using where
1 SIMPLE t2 ALL NULL NULL NULL NULL 3 100.00 Using where; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select `test`.`t1`.`x` AS `LJ2_x1`,`test`.`t1`.`y` AS `y1`,`test`.`t2`.`x` AS `x2`,`test`.`t2`.`y` AS `y2` from `test`.`t1` FOR SYSTEM_TIME ALL left join `test`.`t2` FOR SYSTEM_TIME ALL on(`test`.`t2`.`x` = `test`.`t1`.`x` and `test`.`t1`.`row_end` > @`t0` and `test`.`t1`.`row_start` <= @`t0` and `test`.`t2`.`row_end` > @`t0` and `test`.`t2`.`row_start` <= @`t0`) where 1
Note 1003 select `test`.`t1`.`x` AS `LJ2_x1`,`test`.`t1`.`y` AS `y1`,`test`.`t2`.`x` AS `x2`,`test`.`t2`.`y` AS `y2` from `test`.`t1` FOR SYSTEM_TIME ALL left join `test`.`t2` FOR SYSTEM_TIME ALL on(`test`.`t2`.`x` = `test`.`t1`.`x` and `test`.`t2`.`row_end` > @`t0` and `test`.`t2`.`row_start` <= @`t0`) where `test`.`t1`.`row_end` > @`t0` and `test`.`t1`.`row_start` <= @`t0`
explain extended select * from (select t1.x as RJ2_x1, t1.y as y1, t2.x as x2, t2.y as y2 from t1 right join t2 on t1.x = t2.x)
for system_time as of timestamp @t0 as t;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t2 ALL NULL NULL NULL NULL 3 100.00
1 SIMPLE t2 ALL NULL NULL NULL NULL 3 100.00 Using where
1 SIMPLE t1 ALL NULL NULL NULL NULL 5 100.00 Using where; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select `test`.`t1`.`x` AS `RJ2_x1`,`test`.`t1`.`y` AS `y1`,`test`.`t2`.`x` AS `x2`,`test`.`t2`.`y` AS `y2` from `test`.`t2` FOR SYSTEM_TIME ALL left join `test`.`t1` FOR SYSTEM_TIME ALL on(`test`.`t1`.`x` = `test`.`t2`.`x` and `test`.`t1`.`row_end` > @`t0` and `test`.`t1`.`row_start` <= @`t0` and `test`.`t2`.`row_end` > @`t0` and `test`.`t2`.`row_start` <= @`t0`) where 1
Note 1003 select `test`.`t1`.`x` AS `RJ2_x1`,`test`.`t1`.`y` AS `y1`,`test`.`t2`.`x` AS `x2`,`test`.`t2`.`y` AS `y2` from `test`.`t2` FOR SYSTEM_TIME ALL left join `test`.`t1` FOR SYSTEM_TIME ALL on(`test`.`t1`.`x` = `test`.`t2`.`x` and `test`.`t1`.`row_end` > @`t0` and `test`.`t1`.`row_start` <= @`t0`) where `test`.`t2`.`row_end` > @`t0` and `test`.`t2`.`row_start` <= @`t0`
select * from (select t1.x as IJ2_x1, t1.y as y1, t2.x as x2, t2.y as y2 from t1 inner join t2 on t1.x = t2.x)
for system_time as of timestamp @t0 as t;
IJ2_x1 y1 x2 y2
......@@ -287,6 +287,14 @@ create or replace table t1 (a int) with system versioning;
insert into t1 values (1);
insert into t1 values (2);
insert into t1 values (3);
explain extended
select * from t1 left outer join (t1 as t2 left join t1 as t3 using (a)) on t1.a>1;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 3 100.00 Using where
1 SIMPLE t2 ALL NULL NULL NULL NULL 3 100.00 Using where; Using join buffer (flat, BNL join)
1 SIMPLE t3 ALL NULL NULL NULL NULL 3 100.00 Using where; Using join buffer (incremental, BNL join)
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t2`.`a` AS `a` from `test`.`t1` FOR SYSTEM_TIME ALL left join (`test`.`t1` FOR SYSTEM_TIME ALL `t2` left join `test`.`t1` FOR SYSTEM_TIME ALL `t3` on(`test`.`t3`.`a` = `test`.`t2`.`a` and `test`.`t3`.`row_end` = TIMESTAMP'2038-01-19 03:14:07.999999')) on(`test`.`t2`.`row_end` = TIMESTAMP'2038-01-19 03:14:07.999999' and `test`.`t1`.`a` > 1) where `test`.`t1`.`row_end` = TIMESTAMP'2038-01-19 03:14:07.999999'
select * from t1 left outer join (t1 as t2 left join t1 as t3 using (a)) on t1.a>1;
a a
2 1
......@@ -382,20 +390,24 @@ create or replace table t1 (x int) with system versioning;
select * from t1 for system_time as of current_timestamp;
x
select * from t1 for system_time as of now;
ERROR 42S22: Unknown column 'now' in 'where clause'
ERROR 42S22: Unknown column 'now' in 'on clause'
### Issue #405, NATURAL JOIN failure
create or replace table t1 (a int) with system versioning;
create or replace table t2 (b int);
create or replace view v1 as select a, row_start, row_end from t1 where a > round(rand()*1000);
select * from v1 natural join t2;
a b
### Issue #406, MDEV-14633 Assertion on TRT read
#
# Issue #406, MDEV-14633 Assertion on TRT read
#
create or replace table t1 (pk int primary key, i int, t time, key (i)) with system versioning;
insert into t1 values (1, 10, '15:01:53'), (2, 20, '00:00:00');
delete from t1;
select * from t1 where t = '00:00:00' and i > 0 and row_end <> '2012-12-12 00:00:00';
pk i t
### MDEV-14816 Assertion `join->best_read < double(1.797...e+308L)' failed in bool greedy_search
#
# MDEV-14816 Assertion `join->best_read < double(1.797...e+308L)' failed in bool greedy_search
#
create or replace table t1 (f1 int) with system versioning;
create or replace table t2 (f2 int) with system versioning;
create or replace table t3 (f3 int);
......@@ -464,7 +476,9 @@ f1 f2 f3 f1 f2 f3 f4
3 3 NULL NULL 3 1 1
3 3 NULL NULL 3 2 1
4 NULL NULL NULL NULL NULL NULL
### MDEV-15004 parser greedily parses AS OF TIMESTAMP
#
# MDEV-15004 parser greedily parses AS OF TIMESTAMP
#
select timestamp'2016-02-30 08:07:06';
ERROR HY000: Incorrect DATETIME value: '2016-02-30 08:07:06'
select * from t1 for system_time as of timestamp'2016-02-30 08:07:06';
......@@ -474,6 +488,28 @@ timestamp('2003-12-31 12:00:00','12:00:00')
2004-01-01 00:00:00
select * from t1 for system_time as of timestamp('2003-12-31 12:00:00','12:00:00');
f1
#
# MDEV-15391 Server crashes in JOIN::fix_all_splittings_in_plan or Assertion `join->best_read < double(1.79...e+308L)' failed [tempesta-tech#475]
#
create or replace table t1 (f1 int) with system versioning;
insert t1 values (1),(2);
create or replace table t2 (f2 int);
create or replace table t3 (f3 int);
create or replace table t4 (f4 int) with system versioning;
select f1 from t1 join t2 left join t3 left join t4 on f3 = f4 on f3 = f2;
f1
insert t2 values (1),(2);
insert t3 values (1),(2);
insert t4 values (1),(2);
explain extended
select f1 from t1 join t2 left join t3 left join t4 on f3 = f4 on f3 = f2;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2 100.00 Using where
1 SIMPLE t2 ALL NULL NULL NULL NULL 2 100.00 Using join buffer (flat, BNL join)
1 SIMPLE t3 ALL NULL NULL NULL NULL 2 100.00 Using where; Using join buffer (incremental, BNL join)
1 SIMPLE t4 ALL NULL NULL NULL NULL 2 100.00 Using where; Using join buffer (incremental, BNL join)
Warnings:
Note 1003 select `test`.`t1`.`f1` AS `f1` from `test`.`t1` FOR SYSTEM_TIME ALL join `test`.`t2` left join (`test`.`t3` left join `test`.`t4` FOR SYSTEM_TIME ALL on(`test`.`t4`.`f4` = `test`.`t2`.`f2` and `test`.`t4`.`row_end` = TIMESTAMP'2038-01-19 03:14:07.999999')) on(`test`.`t3`.`f3` = `test`.`t2`.`f2`) where `test`.`t1`.`row_end` = TIMESTAMP'2038-01-19 03:14:07.999999'
drop view v1;
drop table t1, t2, t3, t4;
call verify_vtq_dummy(34);
......
......@@ -182,6 +182,8 @@ create or replace table t1 (a int) with system versioning;
insert into t1 values (1);
insert into t1 values (2);
insert into t1 values (3);
explain extended
select * from t1 left outer join (t1 as t2 left join t1 as t3 using (a)) on t1.a>1;
select * from t1 left outer join (t1 as t2 left join t1 as t3 using (a)) on t1.a>1;
create or replace table t1 (x int) with system versioning;
......@@ -269,7 +271,9 @@ create or replace table t2 (b int);
create or replace view v1 as select a, row_start, row_end from t1 where a > round(rand()*1000);
select * from v1 natural join t2;
--echo ### Issue #406, MDEV-14633 Assertion on TRT read
--echo #
--echo # Issue #406, MDEV-14633 Assertion on TRT read
--echo #
create or replace table t1 (pk int primary key, i int, t time, key (i)) with system versioning;
insert into t1 values (1, 10, '15:01:53'), (2, 20, '00:00:00');
delete from t1;
......@@ -277,7 +281,9 @@ delete from t1;
select * from t1 where t = '00:00:00' and i > 0 and row_end <> '2012-12-12 00:00:00';
--enable_warnings
--echo ### MDEV-14816 Assertion `join->best_read < double(1.797...e+308L)' failed in bool greedy_search
--echo #
--echo # MDEV-14816 Assertion `join->best_read < double(1.797...e+308L)' failed in bool greedy_search
--echo #
create or replace table t1 (f1 int) with system versioning;
create or replace table t2 (f2 int) with system versioning;
create or replace table t3 (f3 int);
......@@ -291,7 +297,9 @@ select * from
left join t2 as t2a left join (t3 as t3a inner join t1) on t2a.f2 = t3a.f3 on t1a.f1 = t2a.f2
left join (t2 join t3 inner join t4) on t2a.f2 = t1a.f1;
--echo ### MDEV-15004 parser greedily parses AS OF TIMESTAMP
--echo #
--echo # MDEV-15004 parser greedily parses AS OF TIMESTAMP
--echo #
--error ER_WRONG_VALUE
select timestamp'2016-02-30 08:07:06';
--error ER_WRONG_VALUE
......@@ -299,6 +307,22 @@ select * from t1 for system_time as of timestamp'2016-02-30 08:07:06';
select timestamp('2003-12-31 12:00:00','12:00:00');
select * from t1 for system_time as of timestamp('2003-12-31 12:00:00','12:00:00');
--echo #
--echo # MDEV-15391 Server crashes in JOIN::fix_all_splittings_in_plan or Assertion `join->best_read < double(1.79...e+308L)' failed [tempesta-tech#475]
--echo #
create or replace table t1 (f1 int) with system versioning;
insert t1 values (1),(2);
create or replace table t2 (f2 int);
create or replace table t3 (f3 int);
create or replace table t4 (f4 int) with system versioning;
select f1 from t1 join t2 left join t3 left join t4 on f3 = f4 on f3 = f2;
insert t2 values (1),(2);
insert t3 values (1),(2);
insert t4 values (1),(2);
explain extended
select f1 from t1 join t2 left join t3 left join t4 on f3 = f4 on f3 = f2;
drop view v1;
drop table t1, t2, t3, t4;
......
......@@ -318,9 +318,13 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds,
DBUG_ASSERT(table);
DBUG_ASSERT(!conds || thd->stmt_arena->is_stmt_execute());
if (select_lex->vers_setup_conds(thd, table_list, &conds))
if (select_lex->vers_setup_conds(thd, table_list))
DBUG_RETURN(TRUE);
DBUG_ASSERT(!conds);
conds= table_list->on_expr;
table_list->on_expr= NULL;
// trx_sees() in InnoDB reads row_start
if (!table->versioned(VERS_TIMESTAMP))
{
......@@ -941,7 +945,7 @@ int mysql_prepare_delete(THD *thd, TABLE_LIST *table_list,
my_error(ER_IT_IS_A_VIEW, MYF(0), table_list->table_name.str);
DBUG_RETURN(true);
}
if (select_lex->vers_setup_conds(thd, table_list, conds))
if (select_lex->vers_setup_conds(thd, table_list))
DBUG_RETURN(true);
}
if ((wild_num && setup_wild(thd, table_list, field_list, NULL, wild_num)) ||
......
......@@ -1044,7 +1044,7 @@ class st_select_lex: public st_select_lex_node
/** System Versioning */
public:
uint versioned_tables;
int vers_setup_conds(THD *thd, TABLE_LIST *tables, COND **where_expr);
int vers_setup_conds(THD *thd, TABLE_LIST *tables);
/* push new Item_field into item_list */
bool vers_push_field(THD *thd, TABLE_LIST *table, const LEX_CSTRING field_name);
......
......@@ -718,7 +718,7 @@ void vers_select_conds_t::print(String *str, enum_query_type query_type)
}
}
int SELECT_LEX::vers_setup_conds(THD *thd, TABLE_LIST *tables, COND **where_expr)
int SELECT_LEX::vers_setup_conds(THD *thd, TABLE_LIST *tables)
{
DBUG_ENTER("SELECT_LEX::vers_setup_cond");
#define newx new (thd->mem_root)
......@@ -777,9 +777,6 @@ int SELECT_LEX::vers_setup_conds(THD *thd, TABLE_LIST *tables, COND **where_expr
}
}
COND** dst_cond= where_expr;
COND* vers_cond= NULL;
for (table= tables; table; table= table->next_local)
{
if (!table->table || !table->table->versioned())
......@@ -830,11 +827,6 @@ int SELECT_LEX::vers_setup_conds(THD *thd, TABLE_LIST *tables, COND **where_expr
lock_type= TL_READ; // ignore TL_WRITE, history is immutable anyway
}
if (table->on_expr)
{
dst_cond= &table->on_expr;
}
const LEX_CSTRING *fstart= &table->table->vers_start_field()->field_name;
const LEX_CSTRING *fend= &table->table->vers_end_field()->field_name;
......@@ -875,7 +867,6 @@ int SELECT_LEX::vers_setup_conds(THD *thd, TABLE_LIST *tables, COND **where_expr
max_time.second_part= TIME_MAX_SECOND_PART;
curr= newx Item_datetime_literal(thd, &max_time, TIME_SECOND_PART_DIGITS);
cond1= newx Item_func_eq(thd, row_end, curr);
cond1= or_items(thd, cond1, newx Item_func_isnull(thd, row_end));
break;
case SYSTEM_TIME_AS_OF:
cond1= newx Item_func_le(thd, row_start, vers_conditions.start.item);
......@@ -938,42 +929,15 @@ int SELECT_LEX::vers_setup_conds(THD *thd, TABLE_LIST *tables, COND **where_expr
DBUG_ASSERT(0);
}
}
vers_conditions.type= SYSTEM_TIME_ALL;
if (cond1)
{
vers_cond= and_items(thd,
vers_cond,
and_items(thd,
cond2,
cond1));
if (table->is_view_or_derived())
vers_cond= or_items(thd, vers_cond, newx Item_func_isnull(thd, row_end));
}
} // for (table= tables; ...)
if (vers_cond)
{
COND *all_cond= and_items(thd, *dst_cond, vers_cond);
bool from_where= dst_cond == where_expr;
if (on_stmt_arena.arena_replaced())
*dst_cond= all_cond;
else
thd->change_item_tree(dst_cond, all_cond);
if (from_where)
{
this->where= *dst_cond;
this->where->top_level_item();
cond1= and_items(thd, cond2, cond1);
table->on_expr= and_items(thd, table->on_expr, cond1);
}
// Invalidate current SP [#52, #422]
if (thd->spcont)
{
DBUG_ASSERT(thd->spcont->m_sp);
thd->spcont->m_sp->set_sp_cache_version(0);
}
}
table->vers_conditions.type= SYSTEM_TIME_ALL;
} // for (table= tables; ...)
DBUG_RETURN(0);
#undef newx
......@@ -1059,7 +1023,7 @@ JOIN::prepare(TABLE_LIST *tables_init,
}
/* System Versioning: handle FOR SYSTEM_TIME clause. */
if (select_lex->vers_setup_conds(thd, tables_list, &conds) < 0)
if (select_lex->vers_setup_conds(thd, tables_list) < 0)
DBUG_RETURN(-1);
/*
......@@ -7533,7 +7497,7 @@ static int compare_embedding_subqueries(JOIN_TAB *jt1, JOIN_TAB *jt2)
b: dependent = 0x0 table->map = 0x2 found_records = 3 ptr = 0x907e838
c: dependent = 0x6 table->map = 0x10 found_records = 2 ptr = 0x907ecd0
As for subuqueries, this function must produce order that can be fed to
As for subqueries, this function must produce order that can be fed to
choose_initial_table_order().
@retval
......@@ -7871,7 +7835,7 @@ greedy_search(JOIN *join,
'best_read < DBL_MAX' means that optimizer managed to find
some plan and updated 'best_positions' array accordingly.
*/
DBUG_ASSERT(join->best_read < DBL_MAX);
DBUG_ASSERT(join->best_read < DBL_MAX);
if (size_remain <= search_depth)
{
......@@ -8629,7 +8593,7 @@ best_extension_by_limited_search(JOIN *join,
/* Find the best access method from 's' to the current partial plan */
POSITION loose_scan_pos;
best_access_path(join, s, remaining_tables, idx, disable_jbuf,
record_count, join->positions + idx, &loose_scan_pos);
record_count, position, &loose_scan_pos);
/* Compute the cost of extending the plan with 's', avoid overflow */
if (position->records_read < DBL_MAX / record_count)
......
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