Item_param::set_value() did not set Item::collation and
Item_param::str_value_ptr.str_charset properly. So both
metadata and data for OUT parameters were sent in a wrong
way to the client.
This patch removes the old implementation of Item_param::set_value()
and rewrites it using Type_handler::Item_param_set_from_value(),
so now setting IN and OUT parameters share the a lot of code.
1. Item_param::set_str() now:
- accepts two additional parameters fromcs, tocs
- sets str_value_ptr, to make sure it's always in sync with str_value,
even without Item_param::convert_str_value()
- does collation.set(tocs, DERIVATION_COERCIBLE),
to make sure that DTCollation is valid even without
Item_param::convert_str_value()
2. Item_param::set_value(), which is used to set OUT parameters,
now reuses Type_handler::Item_param_set_from_value().
3. Cleanup: moving Item_param::str_value_ptr to private,
as it's not needed outside.
4. Cleanup: adding a new virtual method
Settable_routine_parameter::get_item_param()
and using it a few new DBUG_ASSERTs, where
Item_param cannot appear.
After this change:
1. Assigning of IN parameters works as before:
a. Item_param::set_str() is called and sets the value as a binary string
b. The original value is sent to the query used for binary/general logging
c. Item_param::convert_str_value() converts the value from the client
character set to the connection character set
2. Assigning of OUT parameters works in the new way:
a. Item_param::set_str() and sets the value
using the source Item's collation, so both Item::collation
and Item_param::str_value_ptr.str_charset are properly set.
b. Protocol_binary::send_out_parameters() sends the
value to the client correctly:
- Protocol::send_result_set_metadata() uses Item::collation.collation
(which is now properly set), to detect if conversion is needed,
and sends a correct collation ID.
- Protocol::send_result_set_row() calls Type_handler::Item_send_str(),
which uses Item_param::str_value_ptr.str_charset
(which is now properly set) to actually perform the conversion.
Most "new" failures fixed in the following files:
- sql_select.cc
- item.cc
- item_func.cc
- opt_subselect.cc
Other things:
- Allocate udf_handler strings in mem_root
- Required changes in sql_string.h
- Add mem_root as argument to some new [] calls
- Mark udf_handler strings as thread specific
- Removed some comment blocks with code
Issue:
------
VALUES doesn't have a type() function and is considered a
Item_field.
Solution for 5.7:
-----------------
Add a new type() function for Item_values_insert.
On 8.0 and trunk it was fixed by Mithun's Bug#19601973.
Solution for 5.6:
-----------------
Additionally Bug#17458914 is backported.
This will address the problem of using VALUES() in
INSERT ... ON DUPLICATE KEY UPDATE. Create a field object
only if it is in the UPDATE clause, else return a NULL
item.
This will also address the problems mentioned in
Bug#14789787 and Bug#16756402.
Solution for 5.5:
-----------------
As mentioned above Bug#17458914 is backported.
Additionally Bug#14786324 is also backported.
When VALUES() is detected outside its meaningful place,
it should be treated as NULL and is thus replaced with a
Field_null object, with the same name as the original
field.
Fields with type NULL are generally not handled well inside
the server (e.g Innodb will not accept them and it is
impossible to create them in regular tables). So create a
new const NULL item instead.
uses alias in HAVING when sql_mode = 'ONLY_FULL_GROUP_BY'
This patch corrects the patch for bug#18739: non-standard
HAVING extension was allowed in strict ANSI sql mode
added in 2006 by commit 4b7c4cd27f.
As a result of incompleteness of the fix in the above commit
if a query with GROUP BY contained an aggregate function with an
alias and this alias was used in the HAVING clause of the query
the server reported an error when sql_mode was set to
'ONLY_FULL_GROUP_BY'.
Make differentiation between pullout for merge and pulout of outer field during exists2in transformation.
In last case the field was outer and so we can safely start from name resolution context of the SELECT where it was pulled.
Old behavior lead to inconsistence between list of tables and outer name resolution context (which skips one SELECT for merge purposes) which creates problem vor name resolution.
As a result of this merge the code for the following tasks appears in 10.3:
- MDEV-12172 Implement tables specified by table value constructors
- MDEV-12176 Transform [NOT] IN predicate with long list of values INTO
[NOT] IN subquery.
Side effect: the second debug Note in cache_temporal_4265.result disappeared.
Before this change:
- During JOIN::cache_const_exprs(),
Item::get_cache() for Item_date_add_interval() was called.
The data type for date_add('2001-01-01',interval 5 day) is VARCHAR,
because the first argument is VARCHAR (not temporal).
Item_get_cache() created Item_cache_str('2001-01-06').
- During evaluate_join_record(), get_datetime_value() was called,
which called Item::get_date() for Item_cache_str('2001-01-06').
This gave the second Note. Then, get_datetime_value() created
a new cache, now Item_cache_temporal for '2001-01-06', so not
further str_to_datetime() happened.
After this change:
- During tem_bool_rowready_func2::fix_length_and_dec(),
Arg_comparator::set_cmp_func_datetime() is called,
which immediately creates an instance of Item_cache_date for
the result of date_add('2001-01-01',interval 5 day).
So later no str_to_datetime happens any more,
neither during JOIN::cache_const_exprs(),
nor during evaluate_join_record().
- Renaming sp_rcontext::sp to sp_rcontext:m_sp for consistency
with other sp_rcontext_members, and for consistency with the
same purpose member Item_sp_variable::m_sp.
- Passing a "const sp_head*" pointer to sp_rcontext::sp_rcontext()
and to sp_rcontext::create().
Initializing sp_rcontext::m_sp right in the constructor
instead of having a separate initialization after "new sp_rcontext"
or sp_rcontext::create().
- Adding the "const" qualifier to sp_rcontext::m_sp and Item_sp_variable::m_sp
based on:
commit f7316aa0c9
Author: Ajo Robert <ajo.robert@oracle.com>
Date: Thu Aug 24 17:03:21 2017 +0530
Bug#26361149 MYSQL SERVER CRASHES AT: COL IN(IFNULL(CONST,
COL), NAME_CONST('NAME', NULL))
Backport of Bug#19143243 fix.
NAME_CONST item can return NULL_ITEM type in case of incorrect arguments.
NULL_ITEM has special processing in Item_func_in function.
In Item_func_in::fix_length_and_dec an array of possible comparators is
created. Since NAME_CONST function has NULL_ITEM type, corresponding
array element is empty. Then NAME_CONST is wrapped to ITEM_CACHE.
ITEM_CACHE can not return proper type(NULL_ITEM) in Item_func_in::val_int(),
so the NULL_ITEM is attempted compared with an empty comparator.
The fix is to disable the caching of Item_name_const item.
- Implementing stricter data type control for Item_long_func descendants
- Cleanup: renaming Type_handler::can_return_str_ascii() to can_return_text()
(a better name).
- Fix win64 pointer truncation warnings
(usually coming from misusing 0x%lx and long cast in DBUG)
- Also fix printf-format warnings
Make the above mentioned warnings fatal.
- fix pthread_join on Windows to set return value.
This should also fix the MariaDB 10.2.2 bug
MDEV-13826 CREATE FULLTEXT INDEX on encrypted table fails.
MDEV-12634 FIXME: Modify innodb-index-online, innodb-table-online
so that they will write and read merge sort files. InnoDB 5.7
introduced some optimizations to avoid using the files for small tables.
Many collation test results have been adjusted for MDEV-10191.
The problem was introduced by the patch for MDEV-7661,
which (in addition to the fix itself) included an attempt to make
CONVERT/CAST work in the same way with fields
(i.e. return NULL in strict mode if a non-convertable character found).
It appeared to be a bad idea and some users were affected by this
behavior change. Changing CONVERT/CAST not depend on sql_mode
(restoring pre-10.1.4 behavior).
If compiling a non DBUG binary with
-DDBUG_ASSERT_AS_PRINTF asserts will be
changed to printf + stack trace (of stack
trace are enabled).
- Changed #ifndef DBUG_OFF to
#ifdef DBUG_ASSERT_EXISTS
for those DBUG_OFF that was just used to enable
assert
- Assert checking that could greatly impact
performance where changed to DBUG_ASSERT_SLOW which
is not affected by DBUG_ASSERT_AS_PRINTF
- Added one extra option to my_print_stacktrace() to
get more silent in case of stack trace printing as
part of assert.
- Simplified use_trans_cache() to return at once if is_transactional is set
- Indentation and spelling errors fixed
- Don't call signal_update() if update_binlog_end_pos() is called as the
function already calls signal_update()
- Removed not used function wait_for_update_bin_log(), which would cause
errors if ever used.
- Simplified handler::clone() by always allocating 'ref' in ha_open(). To do
this I added an optional MEM_ROOT argument to ha_open() to be used when
allocating 'ref'
- Changed arguments to get_system_var() from LEX_CSTRING to LEX_CSTRING*
- Added THD as argument to create_select_for_variable(). Changed also char*
argument to LEX_CSTRING to avoid strlen() call.
- Change calls to append() to use LEX_CSTRING
- Added sql/mariadb.h file that should be included first by files in sql
directory, if sql_plugin.h is not used (sql_plugin.h adds SHOW variables
that must be done before my_global.h is included)
- Removed a lot of include my_global.h from include files
- Removed include's of some files that my_global.h automatically includes
- Removed duplicated include's of my_sys.h
- Replaced include my_config.h with my_global.h
During statement preparation st_order::item gets set to a value in
ref_ptr_array. During statement execution we were overriding that value,
causing subsequent checks for window functions to return true.
Whenever we do any setting from ref_ptr_array, make sure to always
store the value in all_fields as well.
For function items containing window functions, as MDEV-12336 has
discovered, we don't need to create a separate Item_direct_ref or
Item_aggregate_ref as they will be computed directly from the top-level
item once the window function argument columns are computed.
This patch fills in a serious flaw in the
code that supports condition pushdown into
materialized views / derived tables.
If a predicate happened to contain a reference
to a mergeable view / derived table and it does
not depended directly on the target materialized
view / derived table then the predicate was not
considered as a subject to pusdown to this view
/ derived table.
This is another attempt to fix the bug mdev-12992.
This patch introduces st_select_lex::context_analysis_place for
the place in SELECT where context analysis is currently performed.
It's similar to st_select_lex::parsing_place, but it is used at
the preparation stage.
The problem lies in how CURRENT_ROLE is defined. The
Item_func_current_role inherits from Item_func_sysconst, which defines
a safe_charset_converter to be a const_charset_converter.
During view creation, if there is no role previously set, the current_role()
function returns NULL.
This is captured on item instantiation and the
const_charset_converter call subsequently returns an Item_null.
In turn, the function is replaced with Item_null and the view is
then created with an Item_null instead of Item_func_current_role.
Without this patch, the first SHOW CREATE VIEW from the testcase would
have a where clause of WHERE role_name = NULL, while the second SHOW
CREATE VIEW would show a correctly created view.
The same applies for the DATABASE function, as it can change as well.
There is an additional problem with CURRENT_ROLE() when used in a
prepared statement. During prepared statement creation we used to set
the string_value of the function to the current role as well as the
null_value flag. During execution, if CURRENT_ROLE was not null, the
null_value flag was never set to not-null during fix_fields.
Item_func_current_user however can never be NULL so it did not show this
problem in a view before. At the same time, the CURRENT_USER() can not
be changed between prepared statement execution and creation so the
implementation where the value is stored during fix_fields is
sufficient.
Note also that DATABASE() function behaves differently during prepared
statements. See bug 25843 for details or commit
7e0ad09edf
sql_sequence.read_only: Show that the sequence can be read in
both read-only and read-write mode, and that the sequence remains
accessible after a server restart.
When the SELECT query from a trigger that used a subquery
in its SELECT list was prepared the counter select_n_having_items
was incremented in the constructor Item::Item(THD *thd).
As a result each invocation of the trigger required more and more
memory for the ref_pointer_array for this SELECT.
Made sure that the counter st_select_lex::select_n_having_items
would be incremented only at the first execution of such trigger.
GROUP BY
Issue 1:
--------
This problem occurs in the following conditions:
1) A UNION is present in the subquery of select list and
handles multiple columns.
2) Query has a GROUP BY.
A temporary table is created to handle the UNION.
Item_field objects are based on the expressions of the
result of the UNION (ie. the fake_select_lex). While
checking validity of the columns in the GROUP BY list, the
columns of the temporary table are checked in
Item_ident::local_column. But the Item_field objects
created for the temporary table don't have information like
the Name_resolution_context that they belong to or whether
they are dependent on an outer query. Since these members
are null, incorrect behavior is caused.
This can happen when such Item objects are cached to apply
the IN-to-EXISTS transform for Item_row.
Solution to Issue 1:
--------------------
Context information of the first select in the UNION will
be assigned to the new Item_field objects.
Issue 2:
--------
This problem occurs in the following conditions:
1) A UNION is present in the subquery of select list.
2) A column in the UNION's first SELECT refers to a table
in the outer-query making it a dependent union.
3) GROUP BY column refers to the outer-referencing column.
While resolving the select list with an outer-reference, an
Item_outer_ref object is created to handle the
outer-query's GROUP BY list. The Item_outer_ref object
replaces the Item_field object in the item tree.
Item_outer_ref::fix_fields will be called only while fixing
the inner references of the outer query.
Before resolving the outer-query, an Item_type_holder
object needs to be created to handle the UNION. But as
explained above, the Item_outer_ref object has not been
fixed yet. Having a fixed Item object is a pre-condition
for creating an Item_type_holder.
Solution to Issue 2:
--------------------
Use the reference (real_item()) of an Item_outer_ref object
instead of the object itself while creating an
Item_type_holder.
