Commit c2b9fdb0 authored by Ramil Kalimullin's avatar Ramil Kalimullin

Fix for bug#32426: "FEDERATED query returns corrupt results

 for ORDER BY on a TEXT or VARCHAR field" backported to 5.1.
parent 2e9045c8
......@@ -2153,6 +2153,29 @@ DROP TABLE t1;
End of 5.0 tests
create server 's1' foreign data wrapper 'mysql' options (port 3306);
drop server 's1';
#
# Bug #32426: FEDERATED query returns corrupt results for ORDER BY on a TEXT
#
CREATE TABLE federated.t1(a TEXT);
INSERT INTO federated.t1 VALUES('abc'), ('gh'), ('f'), ('ijk'), ('de');
CREATE TABLE federated.t1(a TEXT) ENGINE=FEDERATED
CONNECTION='mysql://root@127.0.0.1:SLAVE_PORT/federated/t1';
SELECT * FROM federated.t1 ORDER BY A;
a
abc
de
f
gh
ijk
SELECT * FROM federated.t1 ORDER BY A DESC;
a
ijk
gh
f
de
abc
DROP TABLE federated.t1;
DROP TABLE federated.t1;
End of 5.1 tests
SET @@GLOBAL.CONCURRENT_INSERT= @OLD_MASTER_CONCURRENT_INSERT;
SET @@GLOBAL.CONCURRENT_INSERT= @OLD_SLAVE_CONCURRENT_INSERT;
......
......@@ -1971,6 +1971,28 @@ connection default;
create server 's1' foreign data wrapper 'mysql' options (port 3306);
drop server 's1';
--echo #
--echo # Bug #32426: FEDERATED query returns corrupt results for ORDER BY on a TEXT
--echo #
connection slave;
CREATE TABLE federated.t1(a TEXT);
INSERT INTO federated.t1 VALUES('abc'), ('gh'), ('f'), ('ijk'), ('de');
connection master;
--replace_result $SLAVE_MYPORT SLAVE_PORT
eval CREATE TABLE federated.t1(a TEXT) ENGINE=FEDERATED
CONNECTION='mysql://root@127.0.0.1:$SLAVE_MYPORT/federated/t1';
SELECT * FROM federated.t1 ORDER BY A;
SELECT * FROM federated.t1 ORDER BY A DESC;
DROP TABLE federated.t1;
connection slave;
DROP TABLE federated.t1;
connection default;
--echo End of 5.1 tests
SET @@GLOBAL.CONCURRENT_INSERT= @OLD_MASTER_CONCURRENT_INSERT;
connection slave;
......
......@@ -1621,11 +1621,10 @@ int ha_federated::open(const char *name, int mode, uint test_if_locked)
DBUG_ASSERT(mysql == NULL);
ref_length= (table->s->primary_key != MAX_KEY ?
table->key_info[table->s->primary_key].key_length :
table->s->reclength);
ref_length= sizeof(MYSQL_RES *) + sizeof(MYSQL_ROW_OFFSET);
DBUG_PRINT("info", ("ref_length: %u", ref_length));
my_init_dynamic_array(&results, sizeof(MYSQL_RES *), 4, 4);
reset();
DBUG_RETURN(0);
......@@ -1645,21 +1644,17 @@ int ha_federated::open(const char *name, int mode, uint test_if_locked)
int ha_federated::close(void)
{
int retval;
DBUG_ENTER("ha_federated::close");
/* free the result set */
if (stored_result)
{
mysql_free_result(stored_result);
stored_result= 0;
}
free_result();
delete_dynamic(&results);
/* Disconnect from mysql */
mysql_close(mysql);
mysql= NULL;
retval= free_share(share);
DBUG_RETURN(retval);
DBUG_RETURN(free_share(share));
}
/*
......@@ -2326,8 +2321,7 @@ int ha_federated::index_read(uchar *buf, const uchar *key,
{
DBUG_ENTER("ha_federated::index_read");
if (stored_result)
mysql_free_result(stored_result);
free_result();
DBUG_RETURN(index_read_idx_with_result_set(buf, active_index, key,
key_len, find_flag,
&stored_result));
......@@ -2359,7 +2353,8 @@ int ha_federated::index_read_idx(uchar *buf, uint index, const uchar *key,
&mysql_result)))
DBUG_RETURN(retval);
mysql_free_result(mysql_result);
DBUG_RETURN(retval);
results.elements--;
DBUG_RETURN(0);
}
......@@ -2415,18 +2410,20 @@ int ha_federated::index_read_idx_with_result_set(uchar *buf, uint index,
retval= ER_QUERY_ON_FOREIGN_DATA_SOURCE;
goto error;
}
if (!(*result= mysql_store_result(mysql)))
if (!(*result= store_result(mysql)))
{
retval= HA_ERR_END_OF_FILE;
goto error;
}
if (!(retval= read_next(buf, *result)))
DBUG_RETURN(retval);
if ((retval= read_next(buf, *result)))
{
mysql_free_result(*result);
results.elements--;
*result= 0;
table->status= STATUS_NOT_FOUND;
DBUG_RETURN(retval);
}
DBUG_RETURN(0);
error:
table->status= STATUS_NOT_FOUND;
......@@ -2486,12 +2483,6 @@ int ha_federated::read_range_first(const key_range *start_key,
create_where_from_key(&sql_query,
&table->key_info[active_index],
start_key, end_key, 0, eq_range_arg);
if (stored_result)
{
mysql_free_result(stored_result);
stored_result= 0;
}
if (real_query(sql_query.ptr(), sql_query.length()))
{
retval= ER_QUERY_ON_FOREIGN_DATA_SOURCE;
......@@ -2499,14 +2490,13 @@ int ha_federated::read_range_first(const key_range *start_key,
}
sql_query.length(0);
if (!(stored_result= mysql_store_result(mysql)))
if (!(stored_result= store_result(mysql)))
{
retval= HA_ERR_END_OF_FILE;
goto error;
}
retval= read_next(table->record[0], stored_result);
DBUG_RETURN(retval);
DBUG_RETURN(read_next(table->record[0], stored_result));
error:
table->status= STATUS_NOT_FOUND;
......@@ -2516,10 +2506,8 @@ error:
int ha_federated::read_range_next()
{
int retval;
DBUG_ENTER("ha_federated::read_range_next");
retval= rnd_next(table->record[0]);
DBUG_RETURN(retval);
DBUG_RETURN(rnd_next(table->record[0]));
}
......@@ -2585,23 +2573,11 @@ int ha_federated::rnd_init(bool scan)
if (scan)
{
if (stored_result)
{
mysql_free_result(stored_result);
stored_result= 0;
}
if (real_query(share->select_query, strlen(share->select_query)))
goto error;
stored_result= mysql_store_result(mysql);
if (!stored_result)
goto error;
if (real_query(share->select_query, strlen(share->select_query)) ||
!(stored_result= store_result(mysql)))
DBUG_RETURN(stash_remote_error());
}
DBUG_RETURN(0);
error:
DBUG_RETURN(stash_remote_error());
}
......@@ -2615,11 +2591,7 @@ int ha_federated::rnd_end()
int ha_federated::index_end(void)
{
DBUG_ENTER("ha_federated::index_end");
if (stored_result)
{
mysql_free_result(stored_result);
stored_result= 0;
}
free_result();
active_index= MAX_KEY;
DBUG_RETURN(0);
}
......@@ -2680,6 +2652,9 @@ int ha_federated::read_next(uchar *buf, MYSQL_RES *result)
table->status= STATUS_NOT_FOUND; // For easier return
/* Save current data cursor position. */
current_position= result->data_cursor;
/* Fetch a row, insert it back in a row format. */
if (!(row= mysql_fetch_row(result)))
DBUG_RETURN(HA_ERR_END_OF_FILE);
......@@ -2691,24 +2666,38 @@ int ha_federated::read_next(uchar *buf, MYSQL_RES *result)
}
/*
store reference to current row so that we can later find it for
a re-read, update or delete.
In case of federated, a reference is either a primary key or
the whole record.
Called from filesort.cc, sql_select.cc, sql_delete.cc and sql_update.cc.
/**
@brief Store a reference to current row.
@details During a query execution we may have different result sets (RS),
e.g. for different ranges. All the RS's used are stored in
memory and placed in @c results dynamic array. At the end of
execution all stored RS's are freed at once in the
@c ha_federated::reset().
So, in case of federated, a reference to current row is a
stored result address and current data cursor position.
As we keep all RS in memory during a query execution,
we can get any record using the reference any time until
@c ha_federated::reset() is called.
TODO: we don't have to store all RS's rows but only those
we call @c ha_federated::position() for, so we can free memory
where we store other rows in the @c ha_federated::index_end().
@param[in] record record data (unused)
*/
void ha_federated::position(const uchar *record)
void ha_federated::position(const uchar *record __attribute__ ((unused)))
{
DBUG_ENTER("ha_federated::position");
if (table->s->primary_key != MAX_KEY)
key_copy(ref, (uchar *)record, table->key_info + table->s->primary_key,
ref_length);
else
memcpy(ref, record, ref_length);
DBUG_ASSERT(stored_result);
position_called= TRUE;
/* Store result set address. */
memcpy_fixed(ref, &stored_result, sizeof(MYSQL_RES *));
/* Store data cursor position. */
memcpy_fixed(ref + sizeof(MYSQL_RES *), &current_position,
sizeof(MYSQL_ROW_OFFSET));
DBUG_VOID_RETURN;
}
......@@ -2724,23 +2713,19 @@ void ha_federated::position(const uchar *record)
int ha_federated::rnd_pos(uchar *buf, uchar *pos)
{
int result;
MYSQL_RES *result;
DBUG_ENTER("ha_federated::rnd_pos");
ha_statistic_increment(&SSV::ha_read_rnd_count);
if (table->s->primary_key != MAX_KEY)
{
/* We have a primary key, so use index_read_idx to find row */
result= index_read_idx(buf, table->s->primary_key, pos,
ref_length, HA_READ_KEY_EXACT);
}
else
{
/* otherwise, get the old record ref as obtained in ::position */
memcpy(buf, pos, ref_length);
result= 0;
}
table->status= result ? STATUS_NOT_FOUND : 0;
DBUG_RETURN(result);
/* Get stored result set. */
memcpy_fixed(&result, pos, sizeof(MYSQL_RES *));
DBUG_ASSERT(result);
/* Set data cursor position. */
memcpy_fixed(&result->data_cursor, pos + sizeof(MYSQL_RES *),
sizeof(MYSQL_ROW_OFFSET));
/* Read a row. */
DBUG_RETURN(read_next(buf, result));
}
......@@ -2943,6 +2928,16 @@ int ha_federated::reset(void)
insert_dup_update= FALSE;
ignore_duplicates= FALSE;
replace_duplicates= FALSE;
/* Free stored result sets. */
for (uint i= 0; i < results.elements; i++)
{
MYSQL_RES *result;
get_dynamic(&results, (uchar *) &result, i);
mysql_free_result(result);
}
reset_dynamic(&results);
return 0;
}
......@@ -3206,6 +3201,45 @@ bool ha_federated::get_error_message(int error, String* buf)
DBUG_RETURN(FALSE);
}
/**
@brief Store a result set.
@details Call @c mysql_store_result() to save a result set then
append it to the stored results array.
@param[in] mysql MySLQ connection structure.
@return Stored result set (MYSQL_RES object).
*/
MYSQL_RES *ha_federated::store_result(MYSQL *mysql)
{
MYSQL_RES *result= mysql_store_result(mysql);
DBUG_ENTER("ha_federated::store_result");
if (result)
{
(void) insert_dynamic(&results, (uchar*) &result);
}
position_called= FALSE;
DBUG_RETURN(result);
}
void ha_federated::free_result()
{
DBUG_ENTER("ha_federated::free_result");
if (stored_result && !position_called)
{
mysql_free_result(stored_result);
stored_result= 0;
if (results.elements > 0)
results.elements--;
}
DBUG_VOID_RETURN;
}
int ha_federated::external_lock(THD *thd, int lock_type)
{
int error= 0;
......
......@@ -84,6 +84,11 @@ class ha_federated: public handler
FEDERATED_SHARE *share; /* Shared lock info */
MYSQL *mysql; /* MySQL connection */
MYSQL_RES *stored_result;
/**
Array of all stored results we get during a query execution.
*/
DYNAMIC_ARRAY results;
bool position_called;
uint fetch_num; // stores the fetch num
MYSQL_ROW_OFFSET current_position; // Current position used by ::position()
int remote_error_number;
......@@ -251,6 +256,10 @@ public:
THR_LOCK_DATA **store_lock(THD *thd, THR_LOCK_DATA **to,
enum thr_lock_type lock_type); //required
bool get_error_message(int error, String *buf);
MYSQL_RES *store_result(MYSQL *mysql);
void free_result();
int external_lock(THD *thd, int lock_type);
int connection_commit();
int connection_rollback();
......
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