CRASHES WITH AUTO_INCREMENT COLUMN
Description:- Creating a federated table with AUTO_INCREMENT
column using LIKE clause results in a server crash.
Analysis:- Creating a federated table with AUTO_INCREMENT
column using LIKE clause results in a federated server
crash due to the uninitialized connection structure(mysql).
Also due to unassigned connection string for the remote
server, at the time of preparation of "create_info"
structure, the creation of any federated table using LIKE
clause fails with an error, "ERROR 1 (HY000): server name:
'' doesn't exist!". This bug is not only with
AUTO_INCREMENT but in all creations of federated tables with
LIKE clause.
Fix :- In ha_federated::info(), "mysql->insert_id" assigned
to "stats.auto_increment_value" only when there is an
active connection. This fixes the crash issue. For creating
the federated table with LIKE clause, connection string is
assigned at the time of preparation of "create_info"
structure.
COMMUNICATION PACKETS; FEDERATED TABLE
Description:- Execution of FLUSH TABLES on a federated
table which has been idle for wait_timeout (on the remote
server) + tcp_keepalive_time, fails with an error,
"ERROR 1160 (08S01): Got an error writing communication
packets."
Analysis:- During FLUSH TABLE execution the federated
table is closed which will inturn close the federated
connection. While closing the connection, federated server
tries to communincate with the remote server. Since the
connection was idle for wait_timeout(on the remote server)+
tcp_keepalive_time, the socket gets closed. So this
communication fails because of broken pipe and the error is
thrown. But federated connections are expected to reconnect
silently. And also it cannot reconnect because the
"auto_reconnect" variable is set to 0 in "mysql_close()".
Fix:- Before closing the federated connection, in
"ha_federated_close()", a check is added which will verify
wheather the connection is alive or not. If the connection
is not alive, then "mysql->net.error" is set to 2 which
will indicate that the connetion is broken. Also the
setting of "auto_reconnect" variable to 0 is delayed and is
done after "COM_QUIT" command.
NOTE:- For reproducing this issue, "tcp_keepalive_time" has
to be set to a smaller value. This value is set in the
"/proc/sys/net/ipv4/tcp_keepalive_time" file in Unix
systems. So we need root permission for changing it, which
can't be done through mtr test. So submitting the patch
without mtr test.
LOCAL TABLE WHEN ONLY 1 LOCAL ROW
Description: When updating a federated table with UPDATE...
JOIN, the server consistently crashes with Signal 11 when
only 1 row exists in the local table involved in the join
and that 1 row can be joined with a row in the federated
table.
Analysis: Interaction between the federated engine and the
optimizer results in the crash. In our scenario, ie, local
table having only one row, the program is following a
different path because the table is treated as a constant
table by the join optimizer. So in this scenario
"index_read()" is happening in the prepare phase,
since optimizer plan is different for constant table joins.
In this case, "index_read_idx_map()" (inside handler.cc) is
calling "index_read()" and inside "index_read()", matching
rows are fetched and "stored_result" gets populated by
calling "store_result()". And just after "index_read()",
"index_end()" function is called. And in the "index_end()",
its freeing the "stored_result" by calling "free_result()".
So when it reaches the execution phase, in "position()"
function, we are getting assertion at
"DBUG_ASSERT(stored_result);". In all other scenarios (ie,
table with more than 1 row), optimizer plan is different
and "index_read()" is happening in the execution phase.
Fix: So my fix is to have a separate ha_federated member
function for "index_read_idx_map()" which will handle
federated engine separately. So that position() will be
called before index_end() call in constant table scenario.
LOCAL TABLE WHEN ONLY 1 LOCAL ROW
Description: When updating a federated table with UPDATE...
JOIN, the server consistently crashes with Signal 11 when
only 1 row exists in the local table involved in the join
and that 1 row can be joined with a row in the federated
table.
Analysis: Interaction between the federated engine and the
optimizer results in the crash. In our scenario, ie, local
table having only one row, the program is following a
different path because the table is treated as a constant
table by the join optimizer. So in this scenario
"index_read()" is happening in the prepare phase,
since optimizer plan is different for constant table joins.
In this case, "index_read_idx_map()" (inside handler.cc) is
calling "index_read()" and inside "index_read()", matching
rows are fetched and "stored_result" gets populated by
calling "store_result()". And just after "index_read()",
"index_end()" function is called. And in the "index_end()",
its freeing the "stored_result" by calling "free_result()".
So when it reaches the execution phase, in "position()"
function, we are getting assertion at
"DBUG_ASSERT(stored_result);". In all other scenarios (ie,
table with more than 1 row), optimizer plan is different
and "index_read()" is happening in the execution phase.
Fix: So my fix is to have a separate ha_federated member
function for "index_read_idx_map()" which will handle
federated engine separately. So that position() will be
called before index_end() call in constant table scenario.
BUILD/compile-solaris-amd64:
* call cmake directly, don't go through three layers of wrappers
(but preserve the compile-solaris-amd64 file - buildbot uses it for 5.1 and 5.5)
* disable jemalloc, it doesn't compile on our sol10-64 box
storage/federated/ha_federated.cc:
clang warning
storage/tokudb/CMakeLists.txt:
* require cmake-2.8.9, because 2.8.8 doesn't add -fPIC for POSITION_INDEPENDENT_CODE
property that ft-index CMakeLists.txt files are using
Problem description:
Table 't' created with two colums having compound index on both the
columns under innodb/myisam engine at remote machine. In the local
machine same table is created undet the federated engine.
A select having where clause with along 'AND' operation gives wrong
results on local machine.
Analysis:
The given query at federated engine is wrongly transformed by
federated::create_where_from_key() function and the same was sent to
the remote machine. Hence the local machine is showing wrong results.
Given query "select c1 from t where c1 <= 2 and c2 = 1;"
Query transformed, after ha_federated::create_where_from_key() function is:
SELECT `c1`, `c2` FROM `t` WHERE (`c1` IS NOT NULL ) AND
( (`c1` >= 2) AND (`c2` <= 1) ) and the same sent to real_query().
In the above the '<=' and '=' conditions were transformed to '>=' and
'<=' respectively.
ha_federated::create_where_from_key() function behaving as below:
The key_range is having both the start_key and end_key. The start_key
is used to get "(`c1` IS NOT NULL )" part of the where clause, this
transformation is correct. The end_key is used to get "( (`c1` >= 2)
AND (`c2` <= 1) )", which is wrong, here the given conditions('<=' and '=')
are changed as wrong conditions('>=' and '<=').
The end_key is having {key = 0x39fa6d0 "", length = 10, keypart_map = 3,
flag = HA_READ_AFTER_KEY}
The store_length is having value '5'. Based on store_length and length
values the condition values is applied in HA_READ_AFTER_KEY switch case.
The switch case 'HA_READ_AFTER_KEY' is applicable to only the last part of
the end_key and for previous parts it is going to 'HA_READ_KEY_OR_NEXT' case,
here the '>=' is getting added as a condition instead of '<='.
Fix:
Updated the 'if' condition in 'HA_READ_AFTER_KEY' case to affect for all
parts of the end_key. i.e 'i > 0' will used for end_key, Hence added it in
the if condition.
mysql-test/suite/federated/federated.test:
modified the federated.inc file location
mysql-test/suite/federated/federated_archive.test:
modified the federated.inc file location
mysql-test/suite/federated/federated_bug_13118.test:
modified the federated.inc file location
mysql-test/suite/federated/federated_bug_25714.test:
modified the federated.inc file location
mysql-test/suite/federated/federated_bug_35333.test:
modified the federated.inc file location
mysql-test/suite/federated/federated_debug.test:
modified the federated.inc file location
mysql-test/suite/federated/federated_innodb.test:
modified the federated.inc file location
mysql-test/suite/federated/federated_server.test:
modified the federated.inc file location
mysql-test/suite/federated/federated_transactions.test:
modified the federated.inc file location
mysql-test/suite/federated/include/federated.inc:
moved the file from federated suite to federated/include folder
mysql-test/suite/federated/include/federated_cleanup.inc:
moved the file from federated suite to federated/include folder
mysql-test/suite/federated/include/have_federated_db.inc:
moved the file from federated suite to federated/include folder
storage/federated/ha_federated.cc:
updated the 'if condition' in ha_federated::create_where_from_key()
function.
Problem description:
Table 't' created with two colums having compound index on both the
columns under innodb/myisam engine at remote machine. In the local
machine same table is created undet the federated engine.
A select having where clause with along 'AND' operation gives wrong
results on local machine.
Analysis:
The given query at federated engine is wrongly transformed by
federated::create_where_from_key() function and the same was sent to
the remote machine. Hence the local machine is showing wrong results.
Given query "select c1 from t where c1 <= 2 and c2 = 1;"
Query transformed, after ha_federated::create_where_from_key() function is:
SELECT `c1`, `c2` FROM `t` WHERE (`c1` IS NOT NULL ) AND
( (`c1` >= 2) AND (`c2` <= 1) ) and the same sent to real_query().
In the above the '<=' and '=' conditions were transformed to '>=' and
'<=' respectively.
ha_federated::create_where_from_key() function behaving as below:
The key_range is having both the start_key and end_key. The start_key
is used to get "(`c1` IS NOT NULL )" part of the where clause, this
transformation is correct. The end_key is used to get "( (`c1` >= 2)
AND (`c2` <= 1) )", which is wrong, here the given conditions('<=' and '=')
are changed as wrong conditions('>=' and '<=').
The end_key is having {key = 0x39fa6d0 "", length = 10, keypart_map = 3,
flag = HA_READ_AFTER_KEY}
The store_length is having value '5'. Based on store_length and length
values the condition values is applied in HA_READ_AFTER_KEY switch case.
The switch case 'HA_READ_AFTER_KEY' is applicable to only the last part of
the end_key and for previous parts it is going to 'HA_READ_KEY_OR_NEXT' case,
here the '>=' is getting added as a condition instead of '<='.
Fix:
Updated the 'if' condition in 'HA_READ_AFTER_KEY' case to affect for all
parts of the end_key. i.e 'i > 0' will used for end_key, Hence added it in
the if condition.
mysql-test/suite/innodb/t/group_commit_crash.test:
remove autoincrement to avoid rbr being used for insert ... select
mysql-test/suite/innodb/t/group_commit_crash_no_optimize_thread.test:
remove autoincrement to avoid rbr being used for insert ... select
mysys/my_addr_resolve.c:
a pointer to a buffer is returned to the caller -> the buffer cannot be on the stack
mysys/stacktrace.c:
my_vsnprintf() is ok here, in 5.5
COMMUNICATION PACKETS, ERROR_CODE: 1160
If idle FEDERATED table is evicted from the table cache when
a connection to remote server is lost, query that initiated
eviction may fail.
If this query is executed by slave SQL thread it may fail as well.
An error of close was stored in diagnostics area, which was later
attributed to the statement that caused eviction.
With this patch FEDERATED clears an error of close.
COMMUNICATION PACKETS, ERROR_CODE: 1160
If idle FEDERATED table is evicted from the table cache when
a connection to remote server is lost, query that initiated
eviction may fail.
If this query is executed by slave SQL thread it may fail as well.
An error of close was stored in diagnostics area, which was later
attributed to the statement that caused eviction.
With this patch FEDERATED clears an error of close.
mysql-test/lib/My/Options.pm:
My::Options::is_set() now matches both option names and values!
mysql-test/lib/mtr_cases.pm:
1. don't merge --plugin-load here, it's too early
2. don't skip combinations that set --plugin-load just because the test needs another --plugin-load.
Skip *only* if test's --plugin-load matches *exactly* --plugin-load of one of the combinations.
3. if skipping all combinations but one, still assign the test to the combination
mysql-test/mysql-test-run.pl:
1. remove dead code - don't set variables that aren't used.
2. bugfix: allow one-letter combination names
3. in the command line, merge all --plugin-load options in one
storage/federated/ha_federated.cc:
bugfix: garbage character in the generated SELECT query
sql/sql_insert.cc:
CREATE ... IF NOT EXISTS may do nothing, but
it is still not a failure. don't forget to my_ok it.
******
CREATE ... IF NOT EXISTS may do nothing, but
it is still not a failure. don't forget to my_ok it.
sql/sql_table.cc:
small cleanup
******
small cleanup
