fixes).
The legend: on a replication slave, in case a trigger creation
was filtered out because of application of replicate-do-table/
replicate-ignore-table rule, the parsed definition of a trigger was not
cleaned up properly. LEX::sphead member was left around and leaked
memory. Until the actual implementation of support of
replicate-ignore-table rules for triggers by the patch for Bug 24478 it
was never the case that "case SQLCOM_CREATE_TRIGGER"
was not executed once a trigger was parsed,
so the deletion of lex->sphead there worked and the memory did not leak.
The fix:
The real cause of the bug is that there is no 1 or 2 places where
we can clean up the main LEX after parse. And the reason we
can not have just one or two places where we clean up the LEX is
asymmetric behaviour of MYSQLparse in case of success or error.
One of the root causes of this behaviour is the code in Item::Item()
constructor. There, a newly created item adds itself to THD::free_list
- a single-linked list of Items used in a statement. Yuck. This code
is unaware that we may have more than one statement active at a time,
and always assumes that the free_list of the current statement is
located in THD::free_list. One day we need to be able to explicitly
allocate an item in a given Query_arena.
Thus, when parsing a definition of a stored procedure, like
CREATE PROCEDURE p1() BEGIN SELECT a FROM t1; SELECT b FROM t1; END;
we actually need to reset THD::mem_root, THD::free_list and THD::lex
to parse the nested procedure statement (SELECT *).
The actual reset and restore is implemented in semantic actions
attached to sp_proc_stmt grammar rule.
The problem is that in case of a parsing error inside a nested statement
Bison generated parser would abort immediately, without executing the
restore part of the semantic action. This would leave THD in an
in-the-middle-of-parsing state.
This is why we couldn't have had a single place where we clean up the LEX
after MYSQLparse - in case of an error we needed to do a clean up
immediately, in case of success a clean up could have been delayed.
This left the door open for a memory leak.
One of the following possibilities were considered when working on a fix:
- patch the replication logic to do the clean up. Rejected
as breaks module borders, replication code should not need to know the
gory details of clean up procedure after CREATE TRIGGER.
- wrap MYSQLparse with a function that would do a clean up.
Rejected as ideally we should fix the problem when it happens, not
adjust for it outside of the problematic code.
- make sure MYSQLparse cleans up after itself by invoking the clean up
functionality in the appropriate places before return. Implemented in
this patch.
- use %destructor rule for sp_proc_stmt to restore THD - cleaner
than the prevoius approach, but rejected
because needs a careful analysis of the side effects, and this patch is
for 5.0, and long term we need to use the next alternative anyway
- make sure that sp_proc_stmt doesn't juggle with THD - this is a
large work that will affect many modules.
Cleanup: move main_lex and main_mem_root from Statement to its
only two descendants Prepared_statement and THD. This ensures that
when a Statement instance was created for purposes of statement backup,
we do not involve LEX constructor/destructor, which is fairly expensive.
In order to track that the transformation produces equivalent
functionality please check the respective constructors and destructors
of Statement, Prepared_statement and THD - these members were
used only there.
This cleanup is unrelated to the patch.
sql/log_event.cc:
THD::main_lex is private and should not be used.
sql/mysqld.cc:
Move MYSQLerror to sql_yacc.yy as it depends on LEX headers now.
sql/sql_class.cc:
Cleanup: move main_lex and main_mem_root to THD and Prepared_statement
sql/sql_class.h:
Cleanup: move main_lex and main_mem_root to THD and Prepared_statement
sql/sql_lex.cc:
Implement st_lex::restore_lex()
sql/sql_lex.h:
Declare st_lex::restore_lex().
sql/sql_parse.cc:
Consolidate the calls to unit.cleanup() and deletion of lex->sphead
in mysql_parse (COM_QUERY handler)
sql/sql_prepare.cc:
No need to delete lex->sphead to restore memory roots now in case of a
parse error - this is done automatically inside MYSQLparse
sql/sql_trigger.cc:
This code could lead to double deletion apparently, as in case
of an error lex.sphead was never reset.
sql/sql_yacc.yy:
Trap all returns from the parser to ensure that MySQL-specific cleanup
is invoked: we need to restore the global state of THD and LEX in
case of a parsing error. In case of a parsing success this happens as
part of normal grammar reduction process.
into quadxeon.mysql.com:/benchmarks/ext3/TOSAVE/tsmith/bk/maint/mrg0306/50
mysql-test/mysql-test-run.pl:
Auto merged
mysql-test/r/sp.result:
Auto merged
mysql-test/t/sp.test:
Auto merged
sql/item_cmpfunc.cc:
Auto merged
sql/item_cmpfunc.h:
Auto merged
sql/mysqld.cc:
Auto merged
sql/sql_class.cc:
Auto merged
sql/sql_class.h:
Auto merged
sql/sql_parse.cc:
Auto merged
Functions over sum functions wasn't set up correctly for the ORDER BY clause
which leads to a wrong order of the result set.
The split_sum_func() function is called now for each ORDER BY item that
contains a sum function to set it up correctly.
mysql-test/t/order_by.test:
Added a test case for bug#25376: Incomplete setup of ORDER BY clause results in a wrong result.
mysql-test/r/order_by.result:
Added a test case for bug#25376: Incomplete setup of ORDER BY clause results in a wrong result.
sql/sql_select.cc:
Bug#25376: Incomplete setup of ORDER BY clause results in a wrong result.
The split_sum_func() function is called now for each ORDER BY item that
contains a sum function to set it up correctly.
into weblab.(none):/home/marcsql/TREE/mysql-5.0-8407_b
mysql-test/r/view.result:
Auto merged
sql/mysqld.cc:
Auto merged
sql/sp_head.cc:
Auto merged
sql/sp_head.h:
Auto merged
sql/sql_class.cc:
Auto merged
sql/sql_class.h:
Auto merged
sql/sql_update.cc:
Auto merged
sql/table.cc:
Auto merged
sql/table.h:
Auto merged
sql/sql_base.cc:
Manual merge
Bug 18914 (Calling certain SPs from triggers fail)
Bug 20713 (Functions will not not continue for SQLSTATE VALUE '42S02')
Bug 21825 (Incorrect message error deleting records in a table with a
trigger for inserting)
Bug 22580 (DROP TABLE in nested stored procedure causes strange dependency
error)
Bug 25345 (Cursors from Functions)
This fix resolves a long standing issue originally reported with bug 8407,
which affect the behavior of Stored Procedures, Stored Functions and Trigger
in many different ways, causing symptoms reported by all the bugs listed.
In all cases, the root cause of the problem traces back to 8407 and how the
server locks tables involved with sub statements.
Prior to this fix, the implementation of stored routines would:
- compute the transitive closure of all the tables referenced by a top level
statement
- open and lock all the tables involved
- execute the top level statement
"transitive closure of tables" means collecting:
- all the tables,
- all the stored functions,
- all the views,
- all the table triggers
- all the stored procedures
involved, and recursively inspect these objects definition to find more
references to more objects, until the list of every object referenced does
not grow any more.
This mechanism is known as "pre-locking" tables before execution.
The motivation for locking all the tables (possibly) used at once is to
prevent dead locks.
One problem with this approach is that, if the execution path the code
really takes during runtime does not use a given table, and if the table is
missing, the server would not execute the statement.
This in particular has a major impact on triggers, since a missing table
referenced by an update/delete trigger would prevent an insert trigger to run.
Another problem is that stored routines might define SQL exception handlers
to deal with missing tables, but the server implementation would never give
user code a chance to execute this logic, since the routine is never
executed when a missing table cause the pre-locking code to fail.
With this fix, the internal implementation of the pre-locking code has been
relaxed of some constraints, so that failure to open a table does not
necessarily prevent execution of a stored routine.
In particular, the pre-locking mechanism is now behaving as follows:
1) the first step, to compute the transitive closure of all the tables
possibly referenced by a statement, is unchanged.
2) the next step, which is to open all the tables involved, only attempts
to open the tables added by the pre-locking code, but silently fails without
reporting any error or invoking any exception handler is the table is not
present. This is achieved by trapping internal errors with
Prelock_error_handler
3) the locking step only locks tables that were successfully opened.
4) when executing sub statements, the list of tables used by each statements
is evaluated as before. The tables needed by the sub statement are expected
to be already opened and locked. Statement referencing tables that were not
opened in step 2) will fail to find the table in the open list, and only at
this point will execution of the user code fail.
5) when a runtime exception is raised at 4), the instruction continuation
destination (the next instruction to execute in case of SQL continue
handlers) is evaluated.
This is achieved with sp_instr::exec_open_and_lock_tables()
6) if a user exception handler is present in the stored routine, that
handler is invoked as usual, so that ER_NO_SUCH_TABLE exceptions can be
trapped by stored routines. If no handler exists, then the runtime execution
will fail as expected.
With all these changes, a side effect is that view security is impacted, in
two different ways.
First, a view defined as "select stored_function()", where the stored
function references a table that may not exist, is considered valid.
The rationale is that, because the stored function might trap exceptions
during execution and still return a valid result, there is no way to decide
when the view is created if a missing table really cause the view to be invalid.
Secondly, testing for existence of tables is now done later during
execution. View security, which consist of trapping errors and return a
generic ER_VIEW_INVALID (to prevent disclosing information) was only
implemented at very specific phases covering *opening* tables, but not
covering the runtime execution. Because of this existing limitation,
errors that were previously trapped and converted into ER_VIEW_INVALID are
not trapped, causing table names to be reported to the user.
This change is exposing an existing problem, which is independent and will
be resolved separately.
mysql-test/r/information_schema_db.result:
Revised the pre-locking code implementation, aligned the tests.
mysql-test/r/sp-error.result:
Revised the pre-locking code implementation, aligned the tests.
mysql-test/r/sp.result:
Revised the pre-locking code implementation, aligned the tests.
mysql-test/r/trigger.result:
Revised the pre-locking code implementation, aligned the tests.
mysql-test/r/view.result:
Revised the pre-locking code implementation, aligned the tests.
mysql-test/t/sp-error.test:
Revised the pre-locking code implementation, aligned the tests.
mysql-test/t/sp.test:
Revised the pre-locking code implementation, aligned the tests.
mysql-test/t/trigger.test:
Revised the pre-locking code implementation, aligned the tests.
sql/lock.cc:
table->placeholder now checks for schema_table
sql/mysqld.cc:
my_message_sql(): invoke internal exception handlers
sql/sp_head.cc:
exec_open_and_lock_tables(): open and lock tables, or return the
continuation destination of this instruction
sql/sp_head.h:
exec_open_and_lock_tables(): open and lock tables, or return the
continuation destination of this instruction
sql/sql_base.cc:
Prelock_error_handler: delay open table errors until execution
sql/sql_class.cc:
THD: add internal error handler, as an exception mechanism.
sql/sql_class.h:
THD: add internal error handler, as an exception mechanism.
sql/sql_update.cc:
table->placeholder now checks for schema_table
sql/table.cc:
st_table_list::hide_view_error(): masked more errors for view security
sql/table.h:
table->placeholder now checks for schema_table, and unopened tables
- Add test case that shows how slave server hangs in "STOP SLAVE"
when run on MySQL version 5.0.33 compiled with OpenSSL.
Works fine with latest version of MySQL since that problem
has been fixed by patch for bug#24148. The fix has been noted in
the changelog for MySQL 5.0.36
mysql-test/r/rpl_ssl.result:
New BitKeeper file ``mysql-test/r/rpl_ssl.result''
mysql-test/t/rpl_ssl.test:
New BitKeeper file ``mysql-test/t/rpl_ssl.test''
- Add --debugger=dbx
- Fix --debugger=devenv, --debugger=DevEnv and --debugger=/path/devenv
mysql-test/mysql-test-run.pl:
Add support for --debugger=dbx to mysql-test-run.pl
Fix case senitive match for vc, vcexpress or deven
Make it possible to use full path to debugger for
--debugger=/path/vcexpress
into mysql.com:/home/ram/work/b23616/b23616.5.0
mysql-test/r/func_time.result:
Auto merged
mysql-test/t/func_time.test:
Auto merged
sql-common/my_time.c:
Auto merged
The flag alias_name_used was not set on for the outer references
in subqueries. It resulted in replacement of any outer reference
resolved against an alias for a full field name when the frm
representation of a view with a subquery was generated.
If the subquery and the outer query referenced the same table in
their from lists this replacement effectively changed the meaning
of the view and led to wrong results for selects from this view.
Modified several functions to ensure setting the right value of
the alias_name_used flag for outer references resolved against
aliases.
mysql-test/r/view.result:
Added a test case for bug #26560.
mysql-test/t/view.test:
Added a test case for bug #26560.
sql/item.cc:
Fixed bug #26560.
Made the function resolve_ref_in_select_and_group analyze the return
value of the last parameter with the type of the name resolution for
the submitted reference. If the reference has been resolved against
an alias name from select list then its flag alias_name_used is set on.
Now this value is used in Item_field::fix_outer_field to initialize the flag
when the item_ref object is created for an outer reference.
Added a parameter for the second Item_ref::Item_ref constructor to initialize
properly the flag alias_name_used. The default value of the parameter is FALSE.
If this flag is set on at the creation of an object by this constructor it
will never be changed. Corrected appropriately the Item_ref::set_properties
function.
The function Item_ref::print now prints alias name for an outer reference
if the flag alias_name_used is set on.
sql/item.h:
Fixed bug #26560.
Added a parameter for the second Item_ref::Item_ref constructor to initialize
properly the flag alias_name_used. The default value of the parameter is FALSE.
A similar change has been applied to the first Item_direct_ref::Item_direct_ref
constructor.
sql/mysql_priv.h:
Fixed bug #26560.
Added an an enumeration type enum_resolution_type to return info on
how the function find_item_in_list has resolved the submitted item.
The type is used only for this function.
sql/sql_base.cc:
Fixed bug #26560.
Made the last parameter of the function find_field_in_tables return
more detailed information on how the submitted item has been resolved.
Now it says whether the item has been resolved
against an alias name,
or as a field name without alias,
or as a field name hidden by alias,
or was resolved ignoring alias.
sql/sql_select.cc:
Fixed bug #26560.
Took into account the new type of the last parameter of the function
find_item_in_list.
When the ORDER BY clause gets fixed it's allowed to search in the current
item_list in order to find aliased fields and expressions. This is ok for a
SELECT but wrong for an UPDATE statement. If the ORDER BY clause will
contain a non-existing field which is mentioned in the UPDATE set list
then the server will crash due to using of non-existing (0x0) field.
When an Item_field is getting fixed it's allowed to search item list for
aliased expressions and fields only for selects.
sql/sql_base.cc:
Bug#25126: Wrongly resolved field leads to a crash.
When an Item_field is getting fixed it's allowed to search item list for
aliased expressions and fields only for selects.
sql/sql_select.cc:
Bug#25126: Wrongly resolved field leads to a crash.
When an Item_field is getting fixed it's allowed to search item list for
aliased expressions and fields only for selects.
mysql-test/r/update.result:
Added a test case for bug#25126: Wrongly resolved field leads to a crash.
mysql-test/t/update.test:
Added a test case for bug#25126: Wrongly resolved field leads to a crash.
Several problems here :
1. The conversion to double of an hex string const item
was not taking into account the unsigned flag.
2. IN was not behaving in the same was way as comparisons
when performed over an INT/DATE/DATETIME/TIMESTAMP column
and a constant. The ordinary comparisons in that case
convert the constant to an INTEGER value and do int
comparisons. Fixed the IN to do the same.
3. IN is not taking into account the unsigned flag when
calculating <expr> IN (<int_const1>, <int_const2>, ...).
Extended the implementation of IN to store and process
the unsigned flag for its arguments.
mysql-test/r/func_in.result:
Bug #19342: test case
mysql-test/t/func_in.test:
Bug #19342: test case
sql/item.h:
Bug #19342: correct handling of sign in conersion to real.
sql/item_cmpfunc.cc:
Bug #19342: exteneded the IN values list
to support unsigned longlong values.
Correct comparison of integers in IN with
regard of signedness.
Compare DATE/DATETIME/TIMESTAMP values as
integers in IN.
sql/item_cmpfunc.h:
Bug #19342: exteneded the IN values list
to support unsigned longlong values.
Correct comparison of integers in IN with
regard of signedness.
