greedy_search optimizer_search_depth=0
The algorithm inside restore_prev_nj_state failed to
properly update the counters within the NESTED_JOIN
tree. The counter was decremented each time a table in the
node was removed from the QEP, the correct thing to do being
only to decrement it when the last table in the child node
was removed from the plan. This lead to node counters
getting negative values and the plan thus appeared
impossible. An assertion caught this.
Fixed by not recursing up the tree unless the last table in
the join nest node is removed from the plan
data is selected or not
Temporary and permanent tables should live in different
namespaces. In this case, resolving a permanent table
name gave the temporary table, resulting in a name
collision.
The bug happened under the following condition:
- there was a user variable of type REAL, containing NULL value
- there was a table with a NOT_NULL column of any type but REAL, having
default value (or auto increment);
- a row was inserted into the table with the user variable as value.
A warning was emitted here.
The problem was that handling of NULL values of REAL type was not properly
implemented: it didn't expect that REAL NULL value can be assigned to other
data type.
Basically, the problem was that set_field_to_null() was used instead of
set_field_to_null_with_conversions().
The fix is to use the right function, or more generally, to allow conversion of
REAL NULL values to other data types.
Problem:
item->name was NULL for Item_user_var_as_out_param
which made strcmp(something, item->name) crash in the LOAD XML code.
Fix:
- item_func.h: Adding set_name() in constuctor for Item_user_var_as_out_param
- sql_load.cc: Changing the condition in write_execute_load_query_log_event() which
distiguished between Item_user_var_as_out_param and Item_field
from
if (item->name == NULL)
to
if (item->type() == Item::FIELD_ITEM)
- loadxml.result, loadxml.test: adding tests
table
If a temporary table A exists, and a (permanent) table
with the same name is attempted created with
"CREATE TABLE ... AS SELECT", the create would fail with
an error.
1050: Table 'A' already exists
The error occured in MySQL 5.1 releases, but is not
present in MySQL 5.5. This patch adds a regression
test to ensure that the problem does not reoccur.
Problem: after introduction of "WL#2649 Number-to-string conversions"
This query:
SET NAMES cp850; -- Or any other non-latin1 ASCII-based character set
SELECT * FROM t1
WHERE datetime_column='2010-01-01 00:00:00'
started to add extra character set conversion:
SELECT * FROM t1
WHERE CONVERT(datetime_column USING cp850)='2010-01-01 00:00:00';
so index on DATETIME column was not used anymore.
Fix:
avoid convertion of NUMERIC/DATETIME items
(i.e. those with derivation DERIVATION_NUMERIC).
This is the 5.1 merge and extension of the fix.
The server was happily accepting paths in table name in all places a table
name is accepted (e.g. a SELECT). This allowed all users that have some
privilege over some database to read all tables in all databases in all
mysql server instances that the server file system has access to.
Fixed by :
1. making sure no path elements are allowed in quoted table name when
constructing the path (note that the path symbols are still valid in table names
when they're properly escaped by the server).
2. checking the #mysql50# prefixed names the same way they're checked for
path elements in mysql-5.0.
Iterative patch improvement. Previously committed patch
caused wrong result on Windows. The previous patch also
broke secure_file_priv for symlinks since not all file
paths which must be compared against this variable are
normalized using the same norm.
The server variable opt_secure_file_priv wasn't
normalized properly and caused the operations
LOAD DATA INFILE .. INTO TABLE ..
and
SELECT load_file(..)
to do different interpretations of the
--secure-file-priv option.
The patch moves code to the server initialization
routines so that the path always is normalized
once and only once.
It was also intended that setting the option
to an empty string should be equal to
lifting all previously set restrictions. This
is also fixed by this patch.
mysql-test/r/loaddata.result:
* Removed test code which will currently break the much used --mem feature of mtr.
mysql-test/t/loaddata.test:
* Removed test code which will currently break the much used --mem feature of mtr.
sql/item_strfunc.cc:
* Replaced string comparing code on opt_secure_file_priv with an interface which guarantees that both file paths are normalized using the same norm on all platforms.
sql/mysql_priv.h:
* Added signature for is_secure_file_path()
sql/mysqld.cc:
* New function for checking if a path compatible with the secure path restriction.
* Added initialization of the opt_secure_file_priv variable.
sql/sql_class.cc:
* Replaced string comparing code on opt_secure_file_priv with an interface which guarantees that both file paths are normalized using the same norm on all platforms.
sql/sql_load.cc:
* Replaced string comparing code on opt_secure_file_priv with an interface which guarantees that both file paths are normalized using the same norm on all platforms.
There were two problems here:
1. misleading error message
2. abusing KILL QUERY in the test case
1. The server reported "'DELETE FROM t1' failed: 1689: Wait on a lock was
aborted due to a pending exclusive lock", while the proper error message
should be "'DELETE FROM t1' failed: 1317: Query execution was interrupted".
The problem is that the server has two different flags for
signalling that a query is being killed: THD::killed and
mysys_var::abort. The test case triggers a race: sometimes
mysys_var::abort is set earlier than THD::killed. That leads
to the following situation:
- thr_lock() checks mysys_var::abort and returns error status,
since mysys_var::abort is set;
- the caller (mysql_lock_tables()) gets an error from thr_lock(),
but THD::killed is not set, so it decides that thr_lock() couldn't
get a lock due to a pending exclusive lock.
This is a known issue with the server and it's not going to be fixed soon.
5.5 differs from 5.1 here as follows: when thr_lock() returns an error:
- 5.1 continues trying thr_lock() until success;
- 5.5 propagates the error
2. The test case uses KILL QUERY is a highly concurent environment.
The fix is to wait for the dying statement to rest in peace before
executing another DELETE FROM t1.
WHERE predicates containing references to empty tables in a
subquery were handled incorrectly by the optimizer when
executing EXPLAIN. As a result, the optimizer could try to
evaluate such predicates rather than just stop with
"Impossible WHERE noticed after reading const tables" as
it would do in a non-subquery case. This led to valgrind
errors and crashes.
Fixed the code checking the above condition so that subqueries
are not excluded and hence are handled in the same way as top
level SELECTs.
mysql-test/r/explain.result:
Added a test case for bug #48419.
mysql-test/r/ps.result:
Updated test results to take the new (and more correct)
"Extra" comments in execution plans.
mysql-test/t/explain.test:
Added a test case for bug #48419.
sql/sql_select.cc:
There is no point in excluding subqueries from checking
for identically false WHERE conditions.
Conflicts:
Text conflict in configure.in
Text conflict in dbug/dbug.c
Text conflict in mysql-test/r/ps.result
Text conflict in mysql-test/t/ps.test
Text conflict in sql/CMakeLists.txt
Text conflict in sql/ha_ndbcluster.cc
Text conflict in sql/mysqld.cc
Text conflict in sql/sql_plugin.cc
Text conflict in sql/sql_table.cc
during an UPDATE
Extended the fix for bug 29310 to multi-table update:
When a table is being updated it has two set of fields - fields required for
checks of conditions and fields to be updated. A storage engine is allowed
not to retrieve columns marked for update. Due to this fact records can't
be compared to see whether the data has been changed or not. This makes the
server always update records independently of data change.
Now when an auto-updatable timestamp field is present and server sees that
a table handle isn't going to retrieve write-only fields then all of such
fields are marked as to be read to force the handler to retrieve them.
Fix for bug #46947 "Embedded SELECT without FOR UPDATE is
causing a lock", with after-review fixes.
SELECT statements with subqueries referencing InnoDB tables
were acquiring shared locks on rows in these tables when they
were executed in REPEATABLE-READ mode and with statement or
mixed mode binary logging turned on.
This was a regression which were introduced when fixing
bug 39843.
The problem was that for tables belonging to subqueries
parser set TL_READ_DEFAULT as a lock type. In cases when
statement/mixed binary logging at open_tables() time this
type of lock was converted to TL_READ_NO_INSERT lock at
open_tables() time and caused InnoDB engine to acquire
shared locks on reads from these tables. Although in some
cases such behavior was correct (e.g. for subqueries in
DELETE) in case of SELECT it has caused unnecessary locking.
This patch tries to solve this problem by rethinking our
approach to how we handle locking for SELECT and subqueries.
Now we always set TL_READ_DEFAULT lock type for all cases
when we read data. When at open_tables() time this lock
is interpreted as TL_READ_NO_INSERT or TL_READ depending
on whether this statement as a whole or call to function
which uses particular table should be written to the
binary log or not (if yes then statement should be properly
serialized with concurrent statements and stronger lock
should be acquired).
Test coverage is added for both InnoDB and MyISAM.
This patch introduces an "incompatible" change in locking
scheme for subqueries used in SELECT ... FOR UPDATE and
SELECT .. IN SHARE MODE.
In 4.1 the server would use a snapshot InnoDB read for
subqueries in SELECT FOR UPDATE and SELECT .. IN SHARE MODE
statements, regardless of whether the binary log is on or off.
If the user required a different type of read (i.e. locking read),
he/she could request so explicitly by providing FOR UPDATE/IN SHARE MODE
clause for each individual subquery.
On of the patches for 5.0 broke this behaviour (which was not documented
or tested), and started to use locking reads fora all subqueries in SELECT ...
FOR UPDATE/IN SHARE MODE. This patch restored 4.1 behaviour.
mysql-test/include/check_concurrent_insert.inc:
Added auxiliary script which allows to check if statement
reading table allows concurrent inserts in it.
mysql-test/include/check_no_concurrent_insert.inc:
Added auxiliary script which allows to check that statement
reading table doesn't allow concurrent inserts in it.
mysql-test/include/check_no_row_lock.inc:
Added auxiliary script which allows to check if statement
reading table doesn't take locks on its rows.
mysql-test/include/check_shared_row_lock.inc:
Added auxiliary script which allows to check if statement
reading table takes shared locks on some of its rows.
mysql-test/r/bug39022.result:
After bug #46947 'Embedded SELECT without FOR UPDATE is
causing a lock' was fixed test case for bug 39022 has to
be adjusted in order to trigger execution path on which
original problem was encountered.
mysql-test/r/innodb_mysql_lock2.result:
Added coverage for handling of locking in various cases when
we read data from InnoDB tables (includes test case for
bug #46947 'Embedded SELECT without FOR UPDATE is causing a
lock').
mysql-test/r/lock_sync.result:
Added coverage for handling of locking in various cases when
we read data from MyISAM tables.
mysql-test/t/bug39022.test:
After bug #46947 'Embedded SELECT without FOR UPDATE is
causing a lock' was fixed test case for bug 39022 has to
be adjusted in order to trigger execution path on which
original problem was encountered.
mysql-test/t/innodb_mysql_lock2.test:
Added coverage for handling of locking in various cases when
we read data from InnoDB tables (includes test case for
bug #46947 'Embedded SELECT without FOR UPDATE is causing a
lock').
mysql-test/t/lock_sync.test:
Added coverage for handling of locking in various cases when
we read data from MyISAM tables.
sql/log_event.cc:
Since LEX::lock_option member was removed we no longer can
rely on its value in Load_log_event::print_query() to
determine that log event correponds to LOAD DATA CONCURRENT
statement (this was not correct in all situations anyway).
A new Load_log_event's member was introduced as a replacement.
It is initialized at event object construction time and
explicitly indicates whether LOAD DATA was concurrent.
sql/log_event.h:
Since LEX::lock_option member was removed we no longer can
rely on its value in Load_log_event::print_query() to
determine that log event correponds to LOAD DATA CONCURRENT
statement (this was not correct in all situations anyway).
A new Load_log_event's member was introduced as a replacement.
It is initialized at event object construction time and
explicitly indicates whether LOAD DATA was concurrent.
sql/sp_head.cc:
sp_head::reset_lex():
Before parsing substatement reset part of parser state
which needs this (e.g. set Yacc_state::m_lock_type to
default value).
sql/sql_acl.cc:
Since LEX::reset_n_backup_query_tables_list() now also
resets LEX::sql_command member (as it became part of
Query_tables_list class) we have to restore it in cases
when while working with proxy Query_table_list we assume
that LEX::sql_command still corresponds to original SQL
command being executed (for example, when we are logging
statement to the binary log while having Query_tables_list
reset and backed up).
sql/sql_base.cc:
Changed read_lock_type_for_table() to return a weak TL_READ
type of lock in cases when we are executing statement which
won't update tables directly and table doesn't belong to
statement's prelocking list and thus can't be used by a
stored function. It is OK to do so since in this case table
won't be used by statement or function call which will be
written to the binary log, so serializability requirements
for it can be relaxed.
One of results from this change is that SELECTs on InnoDB
tables no longer takes shared row locks for tables which
are used in subqueries (i.e. bug #46947 is fixed).
Another result is that for similar SELECTs on MyISAM tables
concurrent inserts are allowed.
In order to implement this change signature of
read_lock_type_for_table() function was changed to take
pointers to Query_tables_list and TABLE_LIST objects.
sql/sql_base.h:
- Function read_lock_type_for_table() now takes pointers
to Query_tables_list and TABLE_LIST elements as its
arguments since to correctly determine lock type it needs
to know what statement is being performed and whether table
element for which lock type to be determined belongs to
prelocking list.
sql/sql_lex.cc:
- Removed LEX::lock_option and st_select_lex::lock_option
members. Places in parser that were using them now use
Yacc_state::m_lock_type instead.
- To emphasize that LEX::sql_command member is used during
process of opening and locking of tables it was moved to
Query_tables_list class. It is now reset by
Query_tables_list::reset_query_tables_list() method.
sql/sql_lex.h:
- Removed st_select_lex::lock_option member as there is no
real need for per-SELECT lock type (HIGH_PRIORITY option
should apply to the whole statement. FOR UPDATE/LOCK IN
SHARE MODE clauses can be handled without this member).
The main effect which was achieved by introduction of this
member, i.e. using TL_READ_DEFAULT lock type for
subqueries, is now achieved by setting LEX::lock_option
(or rather its replacement - Yacc_state::m_lock_type) to
TL_READ_DEFAULT in almost all cases.
- To emphasize that LEX::sql_command member is used during
process of opening and locking of tables it was moved to
Query_tables_list class.
- Replaced LEX::lock_option with Yacc_state::m_lock_type
in order to emphasize that this value is relevant only
during parsing. Unlike for LEX::lock_option the default
value for Yacc_state::m_lock_type is TL_READ_DEFAULT.
Note that for cases when it is OK to take a "weak" read
lock (e.g. simple SELECT) this lock type will be converted
to TL_READ at open_tables() time. So this change won't
cause negative change in behavior for such statements.
OTOH this change ensures that, for example, for SELECTs
which are used in stored functions TL_READ_NO_INSERT lock
is taken when necessary and as result calls to such stored
functions can be written to the binary log with correct
serialization.
sql/sql_load.cc:
Load_log_event constructor now requires a parameter that
indicates whether LOAD DATA is concurrent.
sql/sql_parse.cc:
LEX::lock_option was replaced with Yacc_state::m_lock_type.
And instead of resetting the latter implicitly in
mysql_init_multi_delete() we do it explicitly in the
places in parser which call this function.
sql/sql_priv.h:
- To be able more easily distinguish high-priority SELECTs
in st_select_lex::print() method added flag for
HIGH_PRIORITY option.
sql/sql_select.cc:
Changed code not to rely on LEX::lock_option to determine
that it is high-priority SELECT. It was replaced with
Yacc_state::m_lock_type which is accessible only at
parse time. So instead of LEX::lock_option we now rely
on a newly introduced flag for st_select_lex::options -
SELECT_HIGH_PRIORITY.
sql/sql_show.cc:
Since LEX::reset_n_backup_query_tables_list() now also
resets LEX::sql_command member (as it became part of
Query_tables_list class) we have to restore it in cases
when while working with proxy Query_table_list we assume
that LEX::sql_command still corresponds to original SQL
command being executed.
sql/sql_table.cc:
Since LEX::reset_query_tables_list() now also resets
LEX::sql_command member (as it became part of
Query_tables_list class) we have to restore value of this
member when this method is called by mysql_admin_table(),
to make this code safe for re-execution.
sql/sql_trigger.cc:
Since LEX::reset_n_backup_query_tables_list() now also
resets LEX::sql_command member (as it became part of
Query_tables_list class) we have to restore it in cases
when while working with proxy Query_table_list we assume
that LEX::sql_command still corresponds to original SQL
command being executed (for example, when we are logging
statement to the binary log while having Query_tables_list
reset and backed up).
sql/sql_update.cc:
Function read_lock_type_for_table() now takes pointers
to Query_tables_list and TABLE_LIST elements as its
arguments since to correctly determine lock type it needs
to know what statement is being performed and whether table
element for which lock type to be determined belongs to
prelocking list.
sql/sql_yacc.yy:
- Removed st_select_lex::lock_option member as there is no
real need for per-SELECT lock type (HIGH_PRIORITY option
should apply to the whole statement. FOR UPDATE/LOCK IN
SHARE MODE clauses can be handled without this member).
The main effect which was achieved by introduction of this
member, i.e. using TL_READ_DEFAULT lock type for
subqueries, is now achieved by setting LEX::lock_option
(or rather its replacement - Yacc_state::m_lock_type) to
TL_READ_DEFAULT in almost all cases.
- Replaced LEX::lock_option with Yacc_state::m_lock_type
in order to emphasize that this value is relevant only
during parsing. Unlike for LEX::lock_option the default
value for Yacc_state::m_lock_type is TL_READ_DEFAULT.
Note that for cases when it is OK to take a "weak" read
lock (e.g. simple SELECT) this lock type will be converted
to TL_READ at open_tables() time. So this change won't
cause negative change in behavior for such statements.
OTOH this change ensures that, for example, for SELECTs
which are used in stored functions TL_READ_NO_INSERT lock
is taken when necessary and as result calls to such stored
functions can be written to the binary log with correct
serialization.
- To be able more easily distinguish high-priority SELECTs
in st_select_lex::print() method we now use new flag
in st_select_lex::options bit-field.
The problem was in an incorrect debug assertion. The expression
used in the failing assertion states that when finding
references matching ORDER BY expressions, there can be only one
reference to a single table. But that does not make any sense,
all test cases for this bug are valid examples with multiple
identical WHERE expressions referencing the same table which
are also present in the ORDER BY list.
Fixed by removing the failing assertion. We also have to take
care of the 'found' counter so that we count multiple
references only once. We rely on this fact later in
eq_ref_table().
mysql-test/r/join.result:
Added a test case for bug #50335.
mysql-test/t/join.test:
Added a test case for bug #50335.
sql/sql_select.cc:
Removing the assertion in eq_ref_table() as it does not make
any sense. We also have to take care of the 'found' counter so
that we count multiple references only once. We rely on this
fact later in eq_ref_table().
Problem: ALTER TABLE ADD INDEX may lead to table copying if there's
numeric field(s) with non-default display width modificator specified.
Fix: compare numeric field's storage lenghts when we decide whether
they can be considered 'equal' for table alteration purposes.
mysql-test/r/error_simulation.result:
Fix for bug#50946: fast index creation still seems to copy the table
- test result.
mysql-test/t/error_simulation.test:
Fix for bug#50946: fast index creation still seems to copy the table
- test case.
sql/field.cc:
Fix for bug#50946: fast index creation still seems to copy the table
- check numeric field's pack lengths instead of it's display lenghts
comparing fields equality for table alteration purposes.
sql/sql_table.cc:
Fix for bug#50946: fast index creation still seems to copy the table
- check compare_tables() result for testing purposes.
Previously installed dynamic plugins are explicitly not loaded
on startup with --skip-grant-tables enabled. However, INSTALL
PLUGIN/UNINSTALL PLUGIN commands are allowed, and result in
inconsistent error messages (reporting duplicate plugin or
plugin does not exist).
This patch adds a check for --skip-grant-tables mode, and
returns error ER_OPTION_PREVENTS_STATEMENT to the user when
the above commands are attempted.
partition if muliple columns used
Problem was that range scanning through the sorted array of
the column list values did not use a correct index calculation.
Fixed by also taking the number of columns in the calculation.
mysql-test/r/partition_column.result:
Bug#52815: LIST COLUMNS doesn't insert rows in correct
partition if muliple columns used
Added test result for bug.
mysql-test/t/partition_column.test:
Bug#52815: LIST COLUMNS doesn't insert rows in correct
partition if muliple columns used
Added test for bug.
sql/sql_partition.cc:
Bug#52815: LIST COLUMNS doesn't insert rows in correct
partition if muliple columns used
list_col_array is a matrix of field values, so one must also
use the number of columns to calculate the correct partition
id.
transaction
BUG#52616 Temp table prevents switch binlog format from STATEMENT to ROW
Post-merge fixes.
mysql-test/include/commit.inc:
Changed the test case as drop temporary is now written to the binary log in row mode.
mysql-test/r/commit_1innodb.result:
Changed the test case as drop temporary is now written to the binary log in row mode.
mysql-test/r/ctype_cp932_binlog_stm.result:
Disabled warning messages because the test runs in both statement and mixed modes.
mysql-test/t/ctype_cp932_binlog_stm.test:
Disabled warning messages because the test runs in both statement and mixed modes.
mysql-test/t/mysqlbinlog.test:
Removed the --short-form due to BUG#18337 what was suppressing the
select * from t5 /* must be (1),(1) */ in row format.
transaction
BUG#52616 Temp table prevents switch binlog format from STATEMENT to ROW
Before the WL#2687 and BUG#46364, every non-transactional change that happened
after a transactional change was written to trx-cache and flushed upon
committing the transaction. WL#2687 and BUG#46364 changed this behavior and
non-transactional changes are now written to the binary log upon committing
the statement.
A binary log event is identified as transactional or non-transactional through
a flag in the Log_event which is set taking into account the underlie storage
engine on what it is stems from. In the current bug, this flag was not being
set properly when the DROP TEMPORARY TABLE was executed.
However, while fixing this bug we figured out that changes to temporary tables
should be always written to the trx-cache if there is an on-going transaction.
Otherwise, binlog events in the reversed order would be produced.
Regarding concurrency, keeping changes to temporary tables in the trx-cache is
also safe as temporary tables are only visible to the owner connection.
In this patch, we classify the following statements as unsafe:
1 - INSERT INTO t_myisam SELECT * FROM t_myisam_temp
2 - INSERT INTO t_myisam_temp SELECT * FROM t_myisam
3 - CREATE TEMPORARY TABLE t_myisam_temp SELECT * FROM t_myisam
On the other hand, the following statements are classified as safe:
1 - INSERT INTO t_innodb SELECT * FROM t_myisam_temp
2 - INSERT INTO t_myisam_temp SELECT * FROM t_innodb
The patch also guarantees that transactions that have a DROP TEMPORARY are
always written to the binary log regardless of the mode and the outcome:
commit or rollback. In particular, the DROP TEMPORARY is extended with the
IF EXISTS clause when the current statement logging format is set to row.
Finally, the patch allows to switch from STATEMENT to MIXED/ROW when there
are temporary tables but the contrary is not possible.
mysql-test/extra/rpl_tests/rpl_binlog_max_cache_size.test:
Updated the test case because
CREATE TEMPORARY TABLE t_innodb_temp SELECT * FROM t_myisam is not unsafe.
mysql-test/extra/rpl_tests/rpl_implicit_commit_binlog.test:
Updated the test case due to the new rules: changes to
temporary tables are written to the binary log in the
boundaries of a transaction if there is any.
mysql-test/extra/rpl_tests/rpl_innodb.test:
Removed comments from the test case that became false after the patch.
mysql-test/extra/rpl_tests/rpl_loaddata.test:
Suppressed warning messages due to the following cases:
1 - INSERT INTO t_myisam SELECT * FROM t_myisam_temp
2 - INSERT INTO t_myisam_temp SELECT * FROM t_myisam
mysql-test/include/ctype_utf8_table.inc:
Suppressed warning messages due to the following cases:
1 - INSERT INTO t_myisam SELECT * FROM t_myisam_temp
2 - INSERT INTO t_myisam_temp SELECT * FROM t_myisam
mysql-test/r/ctype_cp932_binlog_stm.result:
Updated the test case due to the new rules: changes to
temporary tables are written to the binary log in the
boundaries of a transaction if there is any.
mysql-test/suite/binlog/r/binlog_database.result:
Updated the test case due to the new rules: changes to
temporary tables are written to the binary log in the
boundaries of a transaction if there is any.
mysql-test/suite/binlog/r/binlog_innodb_row.result:
Updated the result file.
mysql-test/suite/binlog/r/binlog_multi_engine.result:
Updated the unsafe message.
mysql-test/suite/binlog/r/binlog_row_binlog.result:
Updated the test case due to the new rules: changes to
temporary tables are written to the binary log in the
boundaries of a transaction if there is any.
mysql-test/suite/binlog/r/binlog_row_drop_tmp_tbl.result:
Updated the test case due to the new rules: changes to
temporary tables are written to the binary log in the
boundaries of a transaction if there is any.
mysql-test/suite/binlog/r/binlog_row_mix_innodb_myisam.result:
Updated the test case due to the new rules: changes to
temporary tables are written to the binary log in the
boundaries of a transaction if there is any.
mysql-test/suite/binlog/r/binlog_stm_binlog.result:
Updated the result file.
mysql-test/suite/binlog/r/binlog_stm_mix_innodb_myisam.result:
Updated the test case due to the new rules: changes to
temporary tables are written to the binary log in the
boundaries of a transaction if there is any.
mysql-test/suite/binlog/t/binlog_tmp_table.test:
Suppressed warning messages due to the following cases:
1 - INSERT INTO t_myisam SELECT * FROM t_myisam_temp
2 - INSERT INTO t_myisam_temp SELECT * FROM t_myisam
mysql-test/suite/ndb/r/ndb_binlog_format.result:
Updated the unsafe message.
mysql-test/suite/rpl/r/rpl_concurrency_error.result:
Updated the unsafe message.
mysql-test/suite/rpl/r/rpl_mixed_binlog_max_cache_size.result:
Updated the result file because
CREATE TEMPORARY TABLE t_innodb_temp SELECT * FROM t_myisam is not unsafe.
mysql-test/suite/rpl/r/rpl_mixed_implicit_commit_binlog.result:
Updated the test case due to the new rules: changes to
temporary tables are written to the binary log in the
boundaries of a transaction if there is any.
mysql-test/suite/rpl/r/rpl_mixed_mixing_engines.result:
Updated the test case due to the new rules: changes to
temporary tables are written to the binary log in the
boundaries of a transaction if there is any.
mysql-test/suite/rpl/r/rpl_mixed_row_innodb.result:
Added some comments to ease the understanding of the result file.
mysql-test/suite/rpl/r/rpl_non_direct_mixed_mixing_engines.result:
Updated the test case due to the new rules: changes to
temporary tables are written to the binary log in the
boundaries of a transaction if there is any.
mysql-test/suite/rpl/r/rpl_non_direct_row_mixing_engines.result:
Updated the test case due to the new rules: changes to
temporary tables are written to the binary log in the
boundaries of a transaction if there is any.
mysql-test/suite/rpl/r/rpl_non_direct_stm_mixing_engines.result:
Updated the test case due to the new rules: changes to
temporary tables are written to the binary log in the
boundaries of a transaction if there is any.
mysql-test/suite/rpl/r/rpl_row_drop.result:
Updated the test case due to the new rules: changes to
temporary tables are written to the binary log in the
boundaries of a transaction if there is any.
mysql-test/suite/rpl/r/rpl_row_implicit_commit_binlog.result:
Updated the test case due to the new rules: changes to
temporary tables are written to the binary log in the
boundaries of a transaction if there is any.
mysql-test/suite/rpl/r/rpl_row_mixing_engines.result:
Updated the test case due to the new rules: changes to
temporary tables are written to the binary log in the
boundaries of a transaction if there is any.
mysql-test/suite/rpl/r/rpl_stm_binlog_max_cache_size.result:
Updated the result file because
CREATE TEMPORARY TABLE t_innodb_temp SELECT * FROM t_myisam is not unsafe.
mysql-test/suite/rpl/r/rpl_stm_implicit_commit_binlog.result:
Updated the test case due to the new rules: changes to
temporary tables are written to the binary log in the
boundaries of a transaction if there is any.
mysql-test/suite/rpl/r/rpl_stm_innodb.result:
Added some comments to ease the understanding of the result file.
mysql-test/suite/rpl/r/rpl_stm_mixing_engines.result:
Updated the test case due to the new rules: changes to
temporary tables are written to the binary log in the
boundaries of a transaction if there is any.
mysql-test/suite/rpl/r/rpl_stm_stop_middle_group.result:
Updated the unsafe message.
mysql-test/suite/rpl/r/rpl_temp_temporary.result:
Added a test case.
mysql-test/suite/rpl/t/rpl000013.test:
Suppressed warning messages due to the following cases:
1 - INSERT INTO t_myisam SELECT * FROM t_myisam_temp
2 - INSERT INTO t_myisam_temp SELECT * FROM t_myisam
3 - CREATE TEMPORARY TABLE t_myisam_temp SELECT * FROM t_myisam
mysql-test/suite/rpl/t/rpl_misc_functions.test:
Suppressed warning messages.
mysql-test/suite/rpl/t/rpl_temp_table.test:
Suppressed warning messages due to the following cases:
1 - INSERT INTO t_myisam SELECT * FROM t_myisam_temp
2 - INSERT INTO t_myisam_temp SELECT * FROM t_myisam
3 - CREATE TEMPORARY TABLE t_myisam_temp SELECT * FROM t_myisam
mysql-test/suite/rpl/t/rpl_temp_temporary.test:
Added a test case.
mysql-test/suite/rpl/t/rpl_temporary.test:
Suppressed warning messages due to the following cases:
1 - INSERT INTO t_myisam SELECT * FROM t_myisam_temp
2 - INSERT INTO t_myisam_temp SELECT * FROM t_myisam
3 - CREATE TEMPORARY TABLE t_myisam_temp SELECT * FROM t_myisam
mysql-test/suite/rpl_ndb/r/rpl_ndb_row_implicit_commit_binlog.result:
Updated the test case due to the new rules: changes to
temporary tables are written to the binary log in the
boundaries of a transaction if there is any.
mysql-test/suite/rpl_ndb/r/rpl_truncate_7ndb.result:
Updated the test case to remove references to positions
in the binary log.
mysql-test/suite/rpl_ndb/t/rpl_truncate_7ndb.test:
Updated the test case to remove references to positions
in the binary log.
mysql-test/t/create_select_tmp.test:
Suppressed warning messages due to the following cases:
1 - INSERT INTO t_myisam SELECT * FROM t_myisam_temp
2 - INSERT INTO t_myisam_temp SELECT * FROM t_myisam
3 - CREATE TEMPORARY TABLE t_myisam_temp SELECT * FROM t_myisam
mysql-test/t/ctype_cp932_binlog_stm.test:
Suppressed warning messages due to the following cases:
1 - INSERT INTO t_myisam SELECT * FROM t_myisam_temp
2 - INSERT INTO t_myisam_temp SELECT * FROM t_myisam
3 - CREATE TEMPORARY TABLE t_myisam_temp SELECT * FROM t_myisam
mysql-test/t/mysqlbinlog.test:
Suppressed warning messages due to the following cases:
1 - INSERT INTO t_myisam SELECT * FROM t_myisam_temp
2 - INSERT INTO t_myisam_temp SELECT * FROM t_myisam
3 - CREATE TEMPORARY TABLE t_myisam_temp SELECT * FROM t_myisam
sql/log.cc:
Improved the code by creating several functions to hide decision
on type of engine changed, commit/abort, etc:
. stmt_has_updated_non_trans_table
. trans_has_updated_non_trans_table
. ending_trans
Updated the binlog_rollback function and the use of the
OPTION_KEEP_LOG which indincates when a temporary table was
either created or dropped and as such the command must be
logged if not in MIXED mode and even while rolling back the
transaction.
sql/log.h:
Improved the code by creating several functions to hide decision
on type of engine changed, commit/abort, etc.
sql/log_event.cc:
Removed the setting of the OPTION_KEEP_LOG as it is related to CREATE
TEMPORARY and DROP TEMPORARY and not to the type of engine (i.e.
transactional or non-transactional).
sql/log_event_old.cc:
Removed the setting of the OPTION_KEEP_LOG as it is related to CREATE
TEMPORARY and DROP TEMPORARY and not to the type of engine (i.e.
transactional or non-transactional).
sql/share/errmsg-utf8.txt:
Updated the unsafe message.
sql/sql_class.cc:
Classifies the following statements as unsafe:
1 - INSERT INTO t_myisam SELECT * FROM t_myisam_temp
2 - INSERT INTO t_myisam_temp SELECT * FROM t_myisam
On the other hand, the following statements are classified as safe:
1 - INSERT INTO t_innodb SELECT * FROM t_myisam_temp
2 - INSERT INTO t_myisam_temp SELECT * FROM t_innodb
sql/sql_class.h:
It allows to switch from STATEMENT to MIXED/ROW when there are temporary
tables but the contrary is not possible.
sql/sql_table.cc:
Fixed the case that a DROP/DROP TEMPORARY that affects a temporary table in MIXED
mode is written as a DROP TEMPORARY TABLE IF EXISTS because the table may not exist in the slave and due to the IF EXISTS token an error will never happen
while processing the statement in the slave.
Removed a function that was not being used.
Arg_comparator initializes 'comparators' array in case of
ROW comparison and does not free this array on destruction.
It leads to memory leaks.
The fix:
-added Arg_comparator::cleanup() method which frees
'comparators' array.
-added Item_bool_func2::cleanup() method which calls
Arg_comparator::cleanup() method
mysql-test/r/ps.result:
test case
mysql-test/r/row.result:
test case
mysql-test/t/ps.test:
test case
mysql-test/t/row.test:
test case
sql/item_cmpfunc.h:
-added Arg_comparator::cleanup() method which frees
'comparators' array.
-added Item_bool_func2::cleanup() method which calls
Arg_comparator::cleanup() method
When re-setting (SET GLOBAL debug='') the GLOBAL debug settings the
server was not freeing the data elements from the top (initial) frame
before setting them to 0 without freeing the underlying memory. As these
are global settings there's a chance that something is there already.
Fixed by :
1. making sure the allocated data are cleaned up before re-setting them
while parsing a debug string
2. making sure the stuff allocated in the global settings is freed on
shutdown.
This assertion could be triggered during execution of OPTIMIZE TABLE for
InnoDB tables. As part of optimize for InnoDB tables, the table is recreated
and then opened again. If the reopen failed for any reason, the assertion
would be triggered. This could for example be caused by a concurrent DROP
TABLE executed by a different connection. The reason for the assertion was
that any failures during reopening were ignored.
This patch fixes the problem by making sure that the result of reopening the
table is checked and that any error messages are sent to the client.
Test case added to innodb_mysql_sync.test.
union...order by (select... where...)
The problem is mysql is trying to materialize and
cache the scalar sub-queries at JOIN::optimize
even for EXPLAIN where the number of columns is
totally different from what's expected.
Fixed by not executing the scalar subqueries
for EXPLAIN.
This was a deadlock between CREATE/ALTER/DROP EVENT and a query
accessing both the mysql.event table and I_S.GLOBAL_VARIABLES.
The root of the problem was that the LOCK_event_metadata mutex was
used to both protect the "event_scheduler" global system variable
and the internal event data structures used by CREATE/ALTER/DROP EVENT.
The deadlock would occur if CREATE/ALTER/DROP EVENT held
LOCK_event_metadata while trying to open the mysql.event table,
at the same time as the query had mysql.event open, trying to
lock LOCK_event_metadata to access "event_scheduler".
This bug was fixed in the scope of Bug#51160 by using only
LOCK_global_system_variables to protect "event_scheduler".
This makes it so that the query above won't lock LOCK_event_metadata,
thereby preventing this deadlock from occuring.
This patch contains no code changes.
Test case added to lock_sync.test.
even if myisam-recover is OFF
The problem was that a corrupted MyISAM table was auto repaired
even if the myisam_recover_options server variable (or the
myisam_recover option) was set to OFF.
The reason was that the auto_repair() function, which is supposed
to say if auto repair is to be used, did not use the server variable
setting correctly. This bug was a regression introduced by WL#4738.
This patch fixes the problem by making sure auto_repair() returns
FALSE if myisam_recover_options is set to OFF.
Test case added to myisam.test.
------------------------------------------------------------
revno: 2875.107.114
revision-id: dlenev@mysql.com-20100201114306-cve0yq5akrxjoei0
parent: dlenev@mysql.com-20100121204303-sr6d1436mac7x6vz
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-next-4284-nl-push
timestamp: Mon 2010-02-01 14:43:06 +0300
message:
Implement new type-of-operation-aware metadata locks.
Add a wait-for graph based deadlock detector to the
MDL subsystem.
Fixes bug #46272 "MySQL 5.4.4, new MDL: unnecessary deadlock" and
bug #37346 "innodb does not detect deadlock between update and
alter table".
The first bug manifested itself as an unwarranted abort of a
transaction with ER_LOCK_DEADLOCK error by a concurrent ALTER
statement, when this transaction tried to repeat use of a
table, which it has already used in a similar fashion before
ALTER started.
The second bug showed up as a deadlock between table-level
locks and InnoDB row locks, which was "detected" only after
innodb_lock_wait_timeout timeout.
A transaction would start using the table and modify a few
rows.
Then ALTER TABLE would come in, and start copying rows
into a temporary table. Eventually it would stumble on
the modified records and get blocked on a row lock.
The first transaction would try to do more updates, and get
blocked on thr_lock.c lock.
This situation of circular wait would only get resolved
by a timeout.
Both these bugs stemmed from inadequate solutions to the
problem of deadlocks occurring between different
locking subsystems.
In the first case we tried to avoid deadlocks between metadata
locking and table-level locking subsystems, when upgrading shared
metadata lock to exclusive one.
Transactions holding the shared lock on the table and waiting for
some table-level lock used to be aborted too aggressively.
We also allowed ALTER TABLE to start in presence of transactions
that modify the subject table. ALTER TABLE acquires
TL_WRITE_ALLOW_READ lock at start, and that block all writes
against the table (naturally, we don't want any writes to be lost
when switching the old and the new table). TL_WRITE_ALLOW_READ
lock, in turn, would block the started transaction on thr_lock.c
lock, should they do more updates. This, again, lead to the need
to abort such transactions.
The second bug occurred simply because we didn't have any
mechanism to detect deadlocks between the table-level locks
in thr_lock.c and row-level locks in InnoDB, other than
innodb_lock_wait_timeout.
This patch solves both these problems by moving lock conflicts
which are causing these deadlocks into the metadata locking
subsystem, thus making it possible to avoid or detect such
deadlocks inside MDL.
To do this we introduce new type-of-operation-aware metadata
locks, which allow MDL subsystem to know not only the fact that
transaction has used or is going to use some object but also what
kind of operation it has carried out or going to carry out on the
object.
This, along with the addition of a special kind of upgradable
metadata lock, allows ALTER TABLE to wait until all
transactions which has updated the table to go away.
This solves the second issue.
Another special type of upgradable metadata lock is acquired
by LOCK TABLE WRITE. This second lock type allows to solve the
first issue, since abortion of table-level locks in event of
DDL under LOCK TABLES becomes also unnecessary.
Below follows the list of incompatible changes introduced by
this patch:
- From now on, ALTER TABLE and CREATE/DROP TRIGGER SQL (i.e. those
statements that acquire TL_WRITE_ALLOW_READ lock)
wait for all transactions which has *updated* the table to
complete.
- From now on, LOCK TABLES ... WRITE, REPAIR/OPTIMIZE TABLE
(i.e. all statements which acquire TL_WRITE table-level lock) wait
for all transaction which *updated or read* from the table
to complete.
As a consequence, innodb_table_locks=0 option no longer applies
to LOCK TABLES ... WRITE.
- DROP DATABASE, DROP TABLE, RENAME TABLE no longer abort
statements or transactions which use tables being dropped or
renamed, and instead wait for these transactions to complete.
- Since LOCK TABLES WRITE now takes a special metadata lock,
not compatible with with reads or writes against the subject table
and transaction-wide, thr_lock.c deadlock avoidance algorithm
that used to ensure absence of deadlocks between LOCK TABLES
WRITE and other statements is no longer sufficient, even for
MyISAM. The wait-for graph based deadlock detector of MDL
subsystem may sometimes be necessary and is involved. This may
lead to ER_LOCK_DEADLOCK error produced for multi-statement
transactions even if these only use MyISAM:
session 1: session 2:
begin;
update t1 ... lock table t2 write, t1 write;
-- gets a lock on t2, blocks on t1
update t2 ...
(ER_LOCK_DEADLOCK)
- Finally, support of LOW_PRIORITY option for LOCK TABLES ... WRITE
was abandoned.
LOCK TABLE ... LOW_PRIORITY WRITE from now on has the same
priority as the usual LOCK TABLE ... WRITE.
SELECT HIGH PRIORITY no longer trumps LOCK TABLE ... WRITE in
the wait queue.
- We do not take upgradable metadata locks on implicitly
locked tables. So if one has, say, a view v1 that uses
table t1, and issues:
LOCK TABLE v1 WRITE;
FLUSH TABLE t1; -- (or just 'FLUSH TABLES'),
an error is produced.
In order to be able to perform DDL on a table under LOCK TABLES,
the table must be locked explicitly in the LOCK TABLES list.
@ mysql-test/include/handler.inc
Adjusted test case to trigger an execution path on which bug 41110
"crash with handler command when used concurrently with alter
table" and bug 41112 "crash in mysql_ha_close_table/get_lock_data
with alter table" were originally discovered. Left old test case
which no longer triggers this execution path for the sake of
coverage.
Added test coverage for HANDLER SQL statements and type-aware
metadata locks.
Added a test for the global shared lock and HANDLER SQL.
Updated tests to take into account that the old simple deadlock
detection heuristics was replaced with a graph-based deadlock
detector.
@ mysql-test/r/debug_sync.result
Updated results (see debug_sync.test).
@ mysql-test/r/handler_innodb.result
Updated results (see handler.inc test).
@ mysql-test/r/handler_myisam.result
Updated results (see handler.inc test).
@ mysql-test/r/innodb-lock.result
Updated results (see innodb-lock.test).
@ mysql-test/r/innodb_mysql_lock.result
Updated results (see innodb_mysql_lock.test).
@ mysql-test/r/lock.result
Updated results (see lock.test).
@ mysql-test/r/lock_multi.result
Updated results (see lock_multi.test).
@ mysql-test/r/lock_sync.result
Updated results (see lock_sync.test).
@ mysql-test/r/mdl_sync.result
Updated results (see mdl_sync.test).
@ mysql-test/r/sp-threads.result
SHOW PROCESSLIST output has changed due to the fact that waiting
for LOCK TABLES WRITE now happens within metadata locking
subsystem.
@ mysql-test/r/truncate_coverage.result
Updated results (see truncate_coverage.test).
@ mysql-test/suite/funcs_1/datadict/processlist_val.inc
SELECT FROM I_S.PROCESSLIST output has changed due to fact that
waiting for LOCK TABLES WRITE now happens within metadata locking
subsystem.
@ mysql-test/suite/funcs_1/r/processlist_val_no_prot.result
SELECT FROM I_S.PROCESSLIST output has changed due to fact that
waiting for LOCK TABLES WRITE now happens within metadata locking
subsystem.
@ mysql-test/suite/rpl/t/rpl_sp.test
Updated to a new SHOW PROCESSLIST state name.
@ mysql-test/t/debug_sync.test
Use LOCK TABLES READ instead of LOCK TABLES WRITE as the latter
no longer allows to trigger execution path involving waiting on
thr_lock.c lock and therefore reaching debug sync-point covered
by this test.
@ mysql-test/t/innodb-lock.test
Adjusted test case to the fact that innodb_table_locks=0 option is
no longer supported, since LOCK TABLES WRITE handles all its
conflicts within MDL subsystem.
@ mysql-test/t/innodb_mysql_lock.test
Added test for bug #37346 "innodb does not detect deadlock between
update and alter table".
@ mysql-test/t/lock.test
Added test coverage which checks the fact that we no longer support
DDL under LOCK TABLES on tables which were locked implicitly.
Adjusted existing test cases accordingly.
@ mysql-test/t/lock_multi.test
Added test for bug #46272 "MySQL 5.4.4, new MDL: unnecessary
deadlock". Adjusted other test cases to take into account the
fact that waiting for LOCK TABLES ... WRITE now happens within MDL
subsystem.
@ mysql-test/t/lock_sync.test
Since LOCK TABLES ... WRITE now takes SNRW metadata lock for
tables locked explicitly we have to implicitly lock InnoDB tables
(through view) to trigger the table-level lock conflict between
TL_WRITE and TL_WRITE_ALLOW_WRITE.
@ mysql-test/t/mdl_sync.test
Added basic test coverage for type-of-operation-aware metadata
locks. Also covered with tests some use cases involving HANDLER
statements in which a deadlock could arise.
Adjusted existing tests to take type-of-operation-aware MDL into
account.
@ mysql-test/t/multi_update.test
Update to a new SHOW PROCESSLIST state name.
@ mysql-test/t/truncate_coverage.test
Adjusted test case after making LOCK TABLES WRITE to wait until
transactions that use the table to be locked are completed.
Updated to the changed name of DEBUG_SYNC point.
@ sql/handler.cc
Global read lock functionality has been
moved into a class.
@ sql/lock.cc
Global read lock functionality has been
moved into a class.
Updated code to use the new MDL API.
@ sql/mdl.cc
Introduced new type-of-operation aware metadata locks.
To do this:
- Changed MDL_lock to use one list for waiting requests and one
list for granted requests. For each list, added a bitmap
that holds information what lock types a list contains.
Added a helper class MDL_lock::List to manipulate with granted
and waited lists while keeping the bitmaps in sync
with list contents.
- Changed lock-compatibility functions to use bitmaps that
define compatibility.
- Introduced a graph based deadlock detector inspired by
waiting_threads.c from Maria implementation.
- Now that we have a deadlock detector, and no longer have
a global lock to protect individual lock objects, but rather
use an rw lock per object, removed redundant code for upgrade,
and the global read lock. Changed the MDL API to
no longer require the caller to acquire the global
intention exclusive lock by means of a separate method.
Removed a few more methods that became redundant.
- Removed deadlock detection heuristic, it has been made
obsolete by the deadlock detector.
- With operation-type-aware metadata locks, MDL subsystem has
become aware of potential conflicts between DDL and open
transactions. This made it possible to remove calls to
mysql_abort_transactions_with_shared_lock() from acquisition
paths for exclusive lock and lock upgrade. Now we can simply
wait for these transactions to complete without fear of
deadlock. Function mysql_lock_abort() has also become
unnecessary for all conflicting cases except when a DDL
conflicts with a connection that has an open HANDLER.
@ sql/mdl.h
Introduced new type-of-operation aware metadata locks.
Introduced a graph based deadlock detector and supporting
methods.
Added comments.
God rid of redundant API calls.
Renamed m_lt_or_ha_sentinel to m_trans_sentinel,
since now it guards the global read lock as well as
LOCK TABLES and HANDLER locks.
@ sql/mysql_priv.h
Moved the global read lock functionality into a
class.
Added MYSQL_OPEN_FORCE_SHARED_MDL flag which forces
open_tables() to take MDL_SHARED on tables instead of
metadata locks specified in the parser. We use this to
allow PREPARE run concurrently in presence of
LOCK TABLES ... WRITE.
Added signature for find_table_for_mdl_ugprade().
@ sql/set_var.cc
Global read lock functionality has been
moved into a class.
@ sql/sp_head.cc
When creating TABLE_LIST elements for prelocking or
system tables set the type of request for metadata
lock according to the operation that will be performed
on the table.
@ sql/sql_base.cc
- Updated code to use the new MDL API.
- In order to avoid locks starvation we take upgradable
locks all at once. As result implicitly locked tables no
longer get an upgradable lock. Consequently DDL and FLUSH
TABLES for such tables is prohibited.
find_write_locked_table() was replaced by
find_table_for_mdl_upgrade() function.
open_table() was adjusted to return TABLE instance with
upgradable ticket when necessary.
- We no longer wait for all locks on OT_WAIT back off
action -- only on the lock that caused the wait
conflict. Moreover, now we distinguish cases when we
have to wait due to conflict in MDL and old version
of table in TDC.
- Upate mysql_notify_threads_having_share_locks()
to only abort thr_lock.c waits of threads that
have open HANDLERs, since lock conflicts with only
these threads now can lead to deadlocks not detectable
by the MDL deadlock detector.
- Remove mysql_abort_transactions_with_shared_locks()
which is no longer needed.
@ sql/sql_class.cc
Global read lock functionality has been moved into a class.
Re-arranged code in THD::cleanup() to simplify assert.
@ sql/sql_class.h
Introduced class to incapsulate global read lock
functionality.
Now sentinel in MDL subsystem guards the global read lock
as well as LOCK TABLES and HANDLER locks. Adjusted code
accordingly.
@ sql/sql_db.cc
Global read lock functionality has been moved into a class.
@ sql/sql_delete.cc
We no longer acquire upgradable metadata locks on tables
which are locked by LOCK TABLES implicitly. As result
TRUNCATE TABLE is no longer allowed for such tables.
Updated code to use the new MDL API.
@ sql/sql_handler.cc
Inform MDL_context about presence of open HANDLERs.
Since HANLDERs break MDL protocol by acquiring table-level
lock while holding only S metadata lock on a table MDL
subsystem should take special care about such contexts (Now
this is the only case when mysql_lock_abort() is used).
@ sql/sql_parse.cc
Global read lock functionality has been moved into a class.
Do not take upgradable metadata locks when opening tables
for CREATE TABLE SELECT as it is not necessary and limits
concurrency.
When initializing TABLE_LIST objects before adding them
to the table list set the type of request for metadata lock
according to the operation that will be performed on the
table.
We no longer acquire upgradable metadata locks on tables
which are locked by LOCK TABLES implicitly. As result FLUSH
TABLES is no longer allowed for such tables.
@ sql/sql_prepare.cc
Use MYSQL_OPEN_FORCE_SHARED_MDL flag when opening
tables during PREPARE. This allows PREPARE to run
concurrently in presence of LOCK TABLES ... WRITE.
@ sql/sql_rename.cc
Global read lock functionality has been moved into a class.
@ sql/sql_show.cc
Updated code to use the new MDL API.
@ sql/sql_table.cc
Global read lock functionality has been moved into a class.
We no longer acquire upgradable metadata locks on tables
which are locked by LOCK TABLES implicitly. As result DROP
TABLE is no longer allowed for such tables.
Updated code to use the new MDL API.
@ sql/sql_trigger.cc
Global read lock functionality has been moved into a class.
We no longer acquire upgradable metadata locks on tables
which are locked by LOCK TABLES implicitly. As result
CREATE/DROP TRIGGER is no longer allowed for such tables.
Updated code to use the new MDL API.
@ sql/sql_view.cc
Global read lock functionality has been moved into a class.
Fixed results of wrong merge that led to misuse of GLR API.
CREATE VIEW statement is not a commit statement.
@ sql/table.cc
When resetting TABLE_LIST objects for PS or SP re-execution
set the type of request for metadata lock according to the
operation that will be performed on the table. Do the same
in auxiliary function initializing metadata lock requests
in a table list.
@ sql/table.h
When initializing TABLE_LIST objects set the type of request
for metadata lock according to the operation that will be
performed on the table.
@ sql/transaction.cc
Global read lock functionality has been moved into a class.
