The problem is a shift operation that is not 64-bit safe.
The consequence is that used tables information for a join with 32 tables
or more will be incorrect.
Fixed by adding a type cast in Item_sum::update_used_tables().
Also used the opportunity to fix some other potential bugs by adding an
explicit type-cast to an integer in a left-shift operation.
Some of them were quite harmless, but was fixed in order to get the same
signed-ness as the other operand of the operation it was used in.
sql/item_cmpfunc.cc
Adjusted signed-ness for some integers in left-shift.
sql/item_subselect.cc
Added type-cast to nesting_map (which is a 32/64 bit type, so
potential bug for deeply nested queries).
sql/item_sum.cc
Added type-cast to nesting_map (32/64-bit type) and table_map
(64-bit type).
sql/opt_range.cc
Added type-cast to ulonglong (which is a 64-bit type).
sql/sql_base.cc
Added type-cast to nesting_map (which is a 32/64-bit type).
sql/sql_select.cc
Added type-cast to nesting_map (32/64-bit type) and key_part_map
(64-bit type).
sql/strfunc.cc
Changed type-cast from longlong to ulonglong, to preserve signed-ness.
Analysis:
The following call stack shows that it is possible to set Item_cache::value_cached, and the relevant value
without setting Item_cache::example.
#0 Item_cache_temporal::store_packed at item.cc:8395
#1 get_datetime_value at item_cmpfunc.cc:915
#2 resolve_const_item at item.cc:7987
#3 propagate_cond_constants at sql_select.cc:12264
#4 propagate_cond_constants at sql_select.cc:12227
#5 optimize_cond at sql_select.cc:13026
#6 JOIN::optimize at sql_select.cc:1016
#7 st_select_lex::optimize_unflattened_subqueries at sql_lex.cc:3161
#8 JOIN::optimize_unflattened_subqueries at opt_subselect.cc:4880
#9 JOIN::optimize at sql_select.cc:1554
The fix is to set Item_cache_temporal::example even when the value is
set directly by Item_cache_temporal::store_packed. This makes the
Item_cache_temporal object consistent.
two tests still fail:
main.innodb_icp and main.range_vs_index_merge_innodb
call records_in_range() with both range ends being open
(which triggers an assert)
We set correct cmp_context during preparation to avoid changing it later by Item_field::equal_fields_propagator.
(see mysql bugs #57135#57692 during merging)
make sure that find_date_time_item() is called before agg_arg_charsets_for_comparison().
optimize Item_func_conv_charset to avoid conversion if no string result is needed
Analysis:
When a subquery that needs a temp table is executed during
the prepare or optimize phase of the outer query, at the end
of the subquery execution all the JOIN_TABs of the subquery
are replaced by a new JOIN_TAB that selects from the temp table.
However that temp table has no corresponding TABLE_LIST.
Once EXPLAIN execution reaches its last phase, it tries to print
the names of the subquery tables through its TABLE_LISTs, but in
the case of this bug there is no such TABLE_LIST (it is NULL),
hence a crash.
Solution:
The fix is to block subquery evaluation inside
Item_func_like::fix_fields and Item_func_like::select_optimize()
using the Item::is_expensive() test.
Analysis:
The problem in the original MySQL bug is that the range optimizer
performs its analysis in a separate MEM_ROOT object that is freed
after the range optimzier is done. During range analysis get_mm_tree
calls Item_func_like::select_optimize, which in turn evaluates its
right argument. In the test case the right argument is a subquery.
In MySQL, subqueries are optimized lazyly, thus the call to val_str
triggers optimization for the subquery. All objects needed by the
subquery plan end up in the temporary MEM_ROOT used by the range
optimizer. When execution ends, the JOIN::cleanup process tries to
cleanup objects of the subquery plan, but all these objects are gone
with the temporary MEM_ROOT. The solution for MySQL is to switch the
mem_root.
In MariaDB with the patch for bug lp:944706, all constant subqueries
that may be used by the optimization process are preoptimized. Therefore
Item_func_like::select_optimize only triggers subquery execution, and
the above problem is not present.
The patch however adds a test whether the evaluated right argument of
the LIKE predicate is expensive. This is consistent with our approach
not to evaluate expensive expressions during optimization.
The patch enables back constant subquery execution during
query optimization after it was disabled during the development
of MWL#89 (cost-based choice of IN-TO-EXISTS vs MATERIALIZATION).
The main idea is that constant subqueries are allowed to be executed
during optimization if their execution is not expensive.
The approach is as follows:
- Constant subqueries are recursively optimized in the beginning of
JOIN::optimize of the outer query. This is done by the new method
JOIN::optimize_constant_subqueries(). This is done so that the cost
of executing these queries can be estimated.
- Optimization of the outer query proceeds normally. During this phase
the optimizer may request execution of non-expensive constant subqueries.
Each place where the optimizer may potentially execute an expensive
expression is guarded with the predicate Item::is_expensive().
- The implementation of Item_subselect::is_expensive has been extended
to use the number of examined rows (estimated by the optimizer) as a
way to determine whether the subquery is expensive or not.
- The new system variable "expensive_subquery_limit" controls how many
examined rows are considered to be not expensive. The default is 100.
In addition, multiple changes were needed to make this solution work
in the light of the changes made by MWL#89. These changes were needed
to fix various crashes and wrong results, and legacy bugs discovered
during development.
Issue/Cause:
Issue is of memory corruption.During optimization phase, pattern to be matched in where
clause, is prepared. This is done in Item_func_concat::val_str() function which forms the
resultant string (tmp_value) and return its pointer. In caller, Item_func_like::fix_fields,
pattern is made to point to this string (tmp_value). In further processing, tmp_value is
getting modified which causes pattern to have changed/wrong values.
Fix:
Allocate its own memroy location in caller, copy value of resultant string (tmp_value)
into that and make pattern to point to that. This makes sure no further changes to
tmp_value will affect pattern.
- Fix equality propagation to work with SJM nests and OR clauses (full descirption of problem and
solution in the comment in the patch)
(The second commit with post-review fixes)
make sure that stored routines are evaluated (that is, de facto - cached) in convert_const_to_int().
revert the fix for lp:806943 because it cannot be repeated anymore.
add few tests for convert_const_to_int()
Fixed Item* Item_equal::get_first(JOIN_TAB *context, Item *field_item) to work correctly in the case where:
- context!= NO_PARTICULAR_TAB, it points to a table within SJ-Materialization nest
- field_item points to an item_equal that has a constant Item_field but does not have any fields
from tables that are within semi-join nests.
Bug#11758543 50756: BIGINT '100' MATCHES 1.001E2
Expressions of the form
BIGINT_COL <compare> <non-integer constant>
should be done either as decimal, or float.
Currently however, such comparisons are done as int,
which means that the constant may be truncated,
and yield false positives/negatives for all queries
where compare is '>' '<' '>=' '<=' '=' '!='.
BIGINT_COL IN <list of contstants>
and
BIGINT_COL BETWEEN <constant> AND <constant>
are also affected.
mysql-test/r/bigint.result:
New tests.
mysql-test/r/func_in.result:
BIGINT <=> string comparison should be done as float,
so a warning for the value 'abc' is appropriate.
mysql-test/t/bigint.test:
New tests.
sql/item_cmpfunc.cc:
In convert_constant_item() we verify that the constant item
can be stored in the given field.
For BIGINT columns (MYSQL_TYPE_LONGLONG) we must verify that the
stored constant value is actually comparable as int,
i.e. that the value was not truncated.
For between: compare as int only if both arguments convert correctly to int.
- equality substitution code was geared towards processing WHERE/ON clauses.
that is, it assumed that it was doing substitions on the code that
= wasn't attached to any particular join_tab yet
= was going to be fed to make_join_select() which would take the condition
apart and attach various parts of it to tables inside/outside semi-joins.
- However, somebody added equality substition for ref access. That is, if
we have a ref access on TBL.key=expr, they would do equality substition in
'expr'. This possibility wasn't accounted for.
- Fixed equality substition code by adding a mode that does equality
substition under assumption that the processed expression will be
attached to a certain particular table TBL.
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
- Provide fix_after_pullout() function for Item_in_optimizer and other Item_XXX classes (basically, all of them
that have eval_not_null_tables, which means they have special rules for calculating not_null_tables_cache value)
ALL subquery should return TRUE if subquery rowa set is empty independently
of left part. The problem was that Item_func_(eq,ne,gt,ge,lt,le) do not
call execution of second argument if first is NULL no in this case subquery
will not be executed and when Item_func_not_all calls any_value() of the
subquery or aggregation function which report that there was rows. So for
NULL < ALL (SELECT...) result was FALSE instead of TRUE.
Fix is just swapping of arguments of Item_func_(eq,ne,gt,ge,lt,le) (with
changing the operation if it is needed) so that result will be the same
(for examole a < b is equal to b > a). This fix exploit the fact that
first argument will be executed in any case.
- The problem was that the code that made the check whether the subquery is an AND-part of the WHERE
clause didn't work correctly for nested subqueries. In particular, grand-child subquery in HAVING was
treated as if it was in the WHERE, which eventually caused an assert when replace_where_subcondition
looked for the subquery predicate in the WHERE and couldn't find it there.
- The fix: Removed implementation of "thd_marker approach". thd->thd_marker was used to determine the
location of subquery predicate: setup_conds() would set accordingly it when making the
{where|on_expr}->fix_fields(...)
call so that AND-parts of the WHERE/ON clauses can determine they are the AND-parts.
Item_cond_or::fix_fields(), Item_func::fix_fields(), Item_subselect::fix_fields (this one was missed),
and all other items-that-contain-items had to reset thd->thd_marker before calling fix_fields() for
their children items, so that the children can see they are not AND-parts of WHERE/ON.
- The "thd_marker approach" required that a lot of code in different locations maintains correct value of
thd->thd_marker, so it was replaced with:
- The new approach with mark_as_condition_AND_part does not keep context in thd->thd_marker. Instead,
setup_conds() now calls
{where|on_expr}->mark_as_condition_AND_part()
and implementations of that function make sure that:
- parts of AND-expressions get the mark_as_condition_AND_part() call
- Item_in_subselect objects record that they are AND-parts of WHERE/ON
Analysis:
During the first execution of the query through the stored
procedure, the optimization phase calls
substitute_for_best_equal_field(), which calls
Item_in_optimizer::transform(). The latter replaces
Item_in_subselect::left_expr with args[0] via assignment.
In this test case args[0] is an Item_outer_ref which is
created/deallocated for each re-execution. As a result,
during the second execution Item_in_subselect::left_expr
pointed to freed memory, which resulted in a crash.
Solution:
The solution is to use change_item_tree(), so that the
origianal left expression is restored after each execution.
The bug is a duplicate of MySQL's Bug#11764086,
however MySQL's fix is incomplete for MariaDB, so
this fix is slightly different.
In addition, this patch renames
Item_func_not_all::top_level() to is_top_level_item()
to make it in line with the analogous methods of
Item_in_optimizer, and Item_subselect.
Analysis:
It is possible to determine whether a predicate is
NULL-rejecting only if it is a top-level one. However,
this was not taken into account for Item_in_optimizer.
As a result, a NOT IN predicate was erroneously
considered as NULL-rejecting, and the NULL-complemented
rows generated by the outer join were rejected before
being checked by the NOT IN predicate.
Solution:
Change Item_in_optimizer to be considered as
NULL-rejecting only if it a top-level predicate.
ALL subquery should return TRUE if subquery rowa set is empty independently
of left part. The problem was that Item_func_(eq,ne,gt,ge,lt,le) do not
call execution of second argument if first is NULL no in this case subquery
will not be executed and when Item_func_not_all calls any_value() of the
subquery or aggregation function which report that there was rows. So for
NULL < ALL (SELECT...) result was FALSE instead of TRUE.
Fix is just swapping of arguments of Item_func_(eq,ne,gt,ge,lt,le) (with
changing the operation if it is needed) so that result will be the same
(for examole a < b is equal to b > a). This fix exploit the fact that
first argument will be executed in any case.
mysql-test/r/subselect.result:
The test suite added.
mysql-test/r/subselect_no_mat.result:
The test suite added.
mysql-test/r/subselect_no_opts.result:
The test suite added.
mysql-test/r/subselect_no_semijoin.result:
The test suite added.
mysql-test/r/subselect_scache.result:
The test suite added.
mysql-test/t/subselect.test:
The test suite added.
sql/item_cmpfunc.cc:
Swap arguments creation methods added.
sql/item_cmpfunc.h:
Swap arguments creation methods added.
sql/item_subselect.cc:
Swap arguments of the comparison.
The problem was that optimizer removes some outer references (it they are
constant for example) and the list of outer items built during prepare phase is
not actual during execution phase when we need it as the cache parameters.
First solution was use pointer on pointer on outer reference Item and
initialize temporary table on demand. This solved most problem except case
when optimiser also reduce Item which contains outer references ('OR' in
this bug test suite).
The solution is to build the list of outer reference items on execution
phase (after optimization) on demand (just before temporary table creation)
by walking Item tree and finding outer references among Item_ident
(Item_field/Item_ref) and Item_sum items.
Removed depends_on list (because it is not neede any mnore for the cache, in the place where it was used it replaced with upper_refs).
Added processor (collect_outer_ref_processor) and get_cache_parameters() methods to collect outer references (or other expression parameters in future).
mysql-test/r/subselect_cache.result:
A new test added.
mysql-test/r/subselect_scache.result:
Changes in creating the cache and its paremeters order or adding arguments of aggregate function (which is a parameter also, but this has no influence on the result).
mysql-test/t/subselect_cache.test:
Added a new test.
sql/item.cc:
depends_on removed.
Added processor (collect_outer_ref_processor) and get_cache_parameters() methods to collect outer references.
Item_cache_wrapper collect parameters befor initialization of its cache.
sql/item.h:
depends_on removed.
Added processor (collect_outer_ref_processor) and get_cache_parameters() methods to collect outer references.
sql/item_cmpfunc.cc:
depends_on removed.
Added processor (collect_outer_ref_processor) to collect outer references.
sql/item_cmpfunc.h:
Added processor (collect_outer_ref_processor) to collect outer references.
sql/item_subselect.cc:
depends_on removed.
Added processor get_cache_parameters() method to collect outer references.
sql/item_subselect.h:
depends_on removed.
Added processor get_cache_parameters() method to collect outer references.
sql/item_sum.cc:
Added processor (collect_outer_ref_processor) method to collect outer references.
sql/item_sum.h:
Added processor (collect_outer_ref_processor) and get_cache_parameters() methods to collect outer references.
sql/opt_range.cc:
depends_on removed.
sql/sql_base.cc:
depends_on removed.
sql/sql_class.h:
New iterator added.
sql/sql_expression_cache.cc:
Build of list of items resolved in outer query done just before creating expression cache on the first execution of the subquery which removes influence of optimizer removing items (all optimization already done).
sql/sql_expression_cache.h:
Build of list of items resolved in outer query done just before creating expression cache on the first execution of the subquery which removes influence of optimizer removing items (all optimization already done).
sql/sql_lex.cc:
depends_on removed.
sql/sql_lex.h:
depends_on removed.
sql/sql_list.h:
Added add_unique method to add only unique elements to the list.
sql/sql_select.cc:
Support of new Item list added.
sql/sql_select.h:
Support of new Item list added.
Bug#11766642: crash in Item_field::register_field_in_read_map
with view
(Former 59793)
Prior to the refactoring in this patch, Item_cond_xor behaved
partially as an Item_cond and partially as an Item_func. The
reasoning behind this was that XOR is currently not optimized
(thus should be Item_func instead of Item_cond), but it was
planned optimize it in the future (thus, made Item_cond anyway
to ease optimization later).
Even though Item_cond inherits from Item_func, there are
differences between these two. One difference is that the
arguments are stored differently. Item_cond stores them in a
list while Item_func store them in an args[].
BUG no 45221 was caused by Item_cond_xor storing arguments in
the list while users of the objects would look for them in
args[]. The fix back then was to store the arguments in both
locations.
In this bug, Item_cond_xor initially gets two Item_field
arguments. These are stored in the list inherited from
Item_cond and in args[] inherited from Item_func. During
resolution, find_field_in_view() replaces the Item_fields
stored in the list with Item_direct_view_refs, but args[]
still points to the unresolved Item_fields. This shows that
the fix for 45221 was incorrect.
The refactoring performed in this patch removes the confusion
by making the XOR item an Item_func period. A neg_transformer()
is also implemented for Item_func_xor to improve performance
when negating XOR expressions. An XOR is negated by negating
one of the operands.
Analysis:
This bug is yet another incarnation of the generic problem
where optimization of the outer query triggers evaluation
of a subquery, and this evaluation performs a destructive
change to the subquery plan. Specifically a temp table is
created for the DISTINCT operation that replaces the
original subquery table. Later, select_describe() attempts
to print the table name, however, there is no corresponding
TABLE_LIST object to the internal temp table, so we get a
crash. Execution works fine because it is not interested in
the corresponding TABLE_LIST object (or its name).
Solution:
Similar to other such bugs, block the evaluation of expensive
Items in convert_const_to_int().
OLD VALUE OF INPUT PARAMETER.
The user-visible problem was that CASE-control-flow function
(not CASE-statement) misbehaved in stored routines under some
circumstances. The problem resulted in a crash or wrong data
returned. The error happened when expressions in CASE-function
were not of the same character set.
A CASE-function should return values of the same character set
for all branches. Internally, that means a new Item-instance
for the CONVERT(... USING <some charset>)-function is added
to the item tree when needed. The problem was that such changes
were not properly recorded using THD::change_item_tree(),
thus dangling pointers remain in the item tree after
THD::rollback_item_tree_changes(), which lead to undefined
behavior (i.e. crash / wrong data) for subsequent executions of
the stored routine.
This bug was introduced by a patch for Bug 11753363
(44793 - CHARACTER SETS: CASE CLAUSE, UCS2 OR UTF32, FAILURE).
The fixed function is Item_func_case::fix_length_and_dec().
New CONVERT-items are added in agg_item_set_converter(),
which calls THD::change_item_tree().
The problem was that an intermediate array was passed
to agg_item_set_converter(). Thus, THD::change_item_tree() there
was called on intermediate objects.
Note: those intermediate objects are allocated on THD's
memory root, so it's Ok to put them into "changed item lists".
The fix is to track changes on the correct objects.
microsecond(TIME)
alter table datetime<->datetime(6)
max(TIME), mix(TIME)
mysql-test/t/func_if.test:
fix the test case of avoid overflow
sql/field.cc:
don't use make_date() and make_time()
sql/field.h:
correct eq_def() for temporal fields
sql/item.cc:
move datetime caching from Item_cache_int
to Item_cache_temporal
sql/item.h:
move datetime caching from Item_cache_int
to Item_cache_temporal
sql/item_func.cc:
use existing helper methods, don't duplicate
sql/item_sum.cc:
argument cache must use argument's cmp_type, not result_type.
sql/item_timefunc.cc:
use existing methods, don't tuplicate.
remove unused function.
fix micorseconds() to support TIME argument
sql/mysql_priv.h:
dead code
sql/time.cc:
dead code
compilation error in mysys/my_getsystime.c fixed
some redundant code removed
sec_to_time, time_to_sec, from_unixtime, unix_timestamp, @@timestamp now
use decimal, not double for numbers with a fractional part.
purge_master_logs_before_date() fixed
many bugs in corner cases fixed
mysys/my_getsystime.c:
compilation failure fixed
sql/sql_parse.cc:
don't cut corners. it backfires.
Safety check that could cause core dump when doing create table with virtual column.
mysql-test/mysql-test-run.pl:
Show also warnings from thr_lock (which starts with just Warning, not Warning:)
mysql-test/r/lock.result:
Added test that showed not relevant warning when using table locks.
mysql-test/t/lock.test:
Added test that showed not relevant warning when using table locks.
mysys/thr_lock.c:
Fixed sorting of locks.
(Old sort code didn't handle case where TL_WRITE_CONCURRENT_INSERT must be sorted before TL_WRITE)
Added more information to check_locks warning output.
Fixed wrong testing of multiple different write locks for same table.
sql/item_cmpfunc.cc:
Safety check that could cause core dump when doing create table with virtual column.
A lot of small fixes and new test cases.
client/mysqlbinlog.cc:
Cast removed
client/mysqltest.cc:
Added missing DBUG_RETURN
include/my_pthread.h:
set_timespec_time_nsec() now only takes one argument
mysql-test/t/date_formats.test:
Remove --disable_ps_protocl as now also ps supports microseconds
mysys/my_uuid.c:
Changed to use my_interval_timer() instead of my_getsystime()
mysys/waiting_threads.c:
Changed to use my_hrtime()
sql/field.h:
Added bool special_const_compare() for fields that may convert values before compare (like year)
sql/field_conv.cc:
Added test to get optimal copying of identical temporal values.
sql/item.cc:
Return that item_int is equal if it's positive, even if unsigned flag is different.
Fixed Item_cache_str::save_in_field() to have identical null check as other similar functions
Added proper NULL check to Item_cache_int::save_in_field()
sql/item_cmpfunc.cc:
Don't call convert_constant_item() if there is nothing that is worth converting.
Simplified test when years should be converted
sql/item_sum.cc:
Mark cache values in Item_sum_hybrid as not constants to ensure they are not replaced by other cache values in compare_datetime()
sql/item_timefunc.cc:
Changed sec_to_time() to take a my_decimal argument to ensure we don't loose any sub seconds.
Added Item_temporal_func::get_time() (This simplifies some things)
sql/mysql_priv.h:
Added Lazy_string_decimal()
sql/mysqld.cc:
Added my_decimal constants max_seconds_for_time_type, time_second_part_factor
sql/table.cc:
Changed expr_arena to be of type CONVENTIONAL_EXECUTION to ensure that we don't loose any items that are created by fix_fields()
sql/tztime.cc:
TIME_to_gmt_sec() now sets *in_dst_time_gap in case of errors
This is needed to be able to detect if timestamp is 0
storage/maria/lockman.c:
Changed from my_getsystime() to set_timespec_time_nsec()
storage/maria/ma_loghandler.c:
Changed from my_getsystime() to my_hrtime()
storage/maria/ma_recovery.c:
Changed from my_getsystime() to mmicrosecond_interval_timer()
storage/maria/unittest/trnman-t.c:
Changed from my_getsystime() to mmicrosecond_interval_timer()
storage/xtradb/handler/ha_innodb.cc:
Added support for new time,datetime and timestamp
unittest/mysys/thr_template.c:
my_getsystime() -> my_interval_timer()
unittest/mysys/waiting_threads-t.c:
my_getsystime() -> my_interval_timer()
mysql-test/r/subselect4.result:
Moved test case for LP BUG#718593 into the correct test file subselect_mat_cost_bugs.test.
mysql-test/t/subselect4.test:
Moved test case for LP BUG#718593 into the correct test file subselect_mat_cost_bugs.test.
sql/event_parse_data.cc:
don't use "not_used" variable
sql/item_timefunc.cc:
Item_temporal_func::fix_length_and_dec()
and other changes
sql/item_timefunc.h:
introducing Item_timefunc::fix_length_and_dec()
sql/share/errmsg.txt:
don't say "column X" in the error message that used not only for columns
include/my_time.h:
remove duplicate defines.
cast to ulonglong to avoid overflow
sql/field.cc:
perform sign extension when reading packed TIME values
sql/item_cmpfunc.cc:
when converting a string to a date for the purpose of comparing it with another date,
we should ignore strict sql mode.
sql/item_timefunc.cc:
better error message
sql/item_timefunc.h:
limit decimals appropriately
sql/share/errmsg.txt:
don't refer to an object as a "column" in error messages that are used not only for columns.
When a view is merged into a select all the depended_from fields
pointing to the select of the view should have been corrected to
point to the select where the view is used. It was not done yet.
This could lead to wrong results returned by queries such as
one from the test case for bug 33389.
Correction of outer references required walking through all items
of the proccesed qurery. To avoid this the following solution was
implemented.
Each select now contains a pointer to the select it is merged into
(if there is any). Such pointers allow to get the corrected value
of depended_from on the fly. The function Item_ident::get_depended_from
was introduced for this purpose.
Resolved all conflicts, bad merges and fixed a few minor bugs in the code.
Commented out the queries from multi_update, view, subselect_sj, func_str,
derived_view, view_grant that failed either with crashes in ps-protocol or
with wrong results.
The failures are clear indications of some bugs in the code and these bugs
are to be fixed.
Analysis:
The subquery is evaluated first during ref-optimization of the outer
query because the subquery is considered constant from the perspective
of the outer query. Thus an attempt is made to evaluate the MAX subquery
and use the new constant to drive an index nested loops join.
During this evaluation the inner-most subquery replaces the JOIN_TAB
with a new one that fetches the data from a temp table.
The function select_describe crashes at the lines:
TABLE_LIST *real_table= table->pos_in_table_list;
item_list.push_back(new Item_string(real_table->alias,
strlen(real_table->alias),
cs));
because 'table' is a temp table, and it has no corresponding table
reference. This 'real_table' is NULL, and real_table->alias results
in a crash.
Solution:
In the spirit of MWL#89 prevent the evaluation of expensive predicates
during optimization. This patch prevents the evaluation of expensive
predicates during ref optimization.
sql/item_subselect.h:
Remove unused class member. Not needed for the fix, but noticed now and removed.
Analysis:
During optimization of the subquery, in the call chain:
update_ref_and_keys -> add_key_fields ->
merge_key_fields -> Item_direct_ref::is_null -> Item_cache::is_null
The call to Item_cache::is_null() returns TRUE, which is wrong.
This results in Item_null replacing the field 'f3' in the KEY_FIELD,
then this Item_null is used for index access, producing a wrong result.
The reason why Item_cache::is_null returns wrong result is that
this Item_cache object is a cache of the left operand of IN, and was
updated in Item_in_optimizer::val_int. In MWL#89 the latter method is
called during the execution phase, which is after we optimize the subquery.
Therefore during the optization phase the left operand cache of IN was
not updated.
Solution:
Update the left operand cache during optimization if it is a constant.
This bug fix also discoveres and fixes a wrong IF statement in
convert_constant_item().
- COLUMN_CREATE(column_nr, value, [column_nr,value]...)
- COLUMN_ADD(blob,column_nr, value, column_nr,value]...)
- COLUMN_DELETE(blob, column_nr, column_nr...)
- COLUMN_EXISTS(blob, column_nr)
- COLUMN_LIST(blob, column_nr)
- COLUMN_GET(string, column_nr AS type)
Added cast(X as DOUBLE) and cast(x as INT)
Better warning and error messages for wrong cast's
Created some sub functions to simplify and reuse code.
Added a lot of conversation functions with error/warnings for what went wrong.
Fixed some issues when casting time to datetime.
Added functions to dynamic strings and Strings to allow one to move a string buffer from dynamic strings to String (to save malloc+ copy)
Added dynamic columns library to libmysqlclient
include/Makefile.am:
Added ma_dyncol.h
include/decimal.h:
Added 'const' to arguments for some functions.
include/my_sys.h:
Added dynstr_reassociate()
include/my_time.h:
Added TIME_SUBSECOND_RANGE
Added double_to_datetime()
Added flag argument to str_to_time()
libmysql/CMakeLists.txt:
Added mysys/ma_dyncol.c
libmysql/Makefile.shared:
Added ma_dyncol
libmysql/libmysql.c:
Added argument to str_to_time()
mysql-test/r/bigint.result:
Better error messages
mysql-test/r/cast.result:
Better warning and error messages
A lot of new cast() tests
mysql-test/r/func_math.result:
Better warning messages
mysql-test/r/func_str.result:
Better warning messages
mysql-test/r/func_time.result:
Better warning messages
mysql-test/r/sp-vars.result:
Better warning messages
mysql-test/r/strict.result:
Better warning messages
New test result
mysql-test/r/type_newdecimal.result:
Better warning messages
mysql-test/r/warnings.result:
Better warning messages
mysql-test/suite/funcs_1/r/innodb_func_view.result:
Updated results after better cast warnings
mysql-test/suite/funcs_1/r/memory_func_view.result:
Updated results after better cast warnings
mysql-test/suite/funcs_1/r/myisam_func_view.result:
Updated results after better cast warnings
mysql-test/suite/optimizer_unfixed_bugs/t/bug43448.test:
Added begin...commit to speed up test.
mysql-test/suite/parts/inc/part_supported_sql_funcs_delete.inc:
Added begin...commit to speed up test.
mysql-test/suite/parts/inc/partition_supported_sql_funcs.inc:
Added begin...commit to speed up test.
mysql-test/suite/parts/r/part_supported_sql_func_innodb.result:
Added begin...commit to speed up test.
mysql-test/suite/parts/r/part_supported_sql_func_myisam.result:
Added begin...commit to speed up test.
mysql-test/suite/parts/r/rpl_partition.result:
Added begin...commit to speed up test.
mysql-test/suite/parts/t/part_supported_sql_func_innodb.test:
Removed duplicated --big_test
mysql-test/suite/parts/t/rpl_partition.test:
Added begin...commit to speed up test.
mysql-test/suite/pbxt/r/cast.result:
Updated results after better cast warnings
mysql-test/suite/pbxt/r/func_str.result:
Updated results after better cast warnings
mysql-test/suite/pbxt/r/type_newdecimal.result:
Updated results after better cast warnings
mysql-test/suite/rpl/r/rpl_innodb_bug28430.result:
Added begin...commit to speed up test.
mysql-test/suite/rpl/t/rpl_innodb_bug28430.test:
Added begin...commit to speed up test.
mysql-test/suite/vcol/r/vcol_supported_sql_funcs_innodb.result:
More warnings
mysql-test/suite/vcol/r/vcol_supported_sql_funcs_myisam.result:
More warnings
mysql-test/t/cast.test:
A lot of new cast() tests
mysql-test/t/strict.test:
Added new test
mysys/CMakeLists.txt:
Added ma_dyncol.c
mysys/Makefile.am:
Added ma_dyncol.c
mysys/string.c:
Added dynstr_reassociate() to move a buffer from dynamic_strings to some other allocator
sql-common/my_time.c:
Added 'fuzzydate' flag to str_to_time()
Added support for microseconds to my_time_to_str() and my_datetime_to_str()
Reset second_parts in number_to_datetime()
Added double_to_datetime()
sql/field.cc:
Added double_to_longlong() and truncate_double() to simplify and reuse code
sql/field.h:
New prototypes
sql/item.cc:
Changed Item::get_date(MYSQL_TIME *ltime,uint fuzzydate) to be aware of type of argument.
(Needed to make it microsecond safe and get better warnings).
Updated call to str_to_time_with_warn()
sql/item.h:
Added struct st_dyncall_create_def used by dynamic columns
Added virtual bool dynamic_result() to tell if type of argument may change over calls.
sql/item_cmpfunc.cc:
Added Item_func_dyncol_exists()
sql/item_cmpfunc.h:
Added class Item_func_dyncol_exists
sql/item_create.cc:
Added get_length_and_scale() to simplify other functions
Simplified and extended create_func_cast()
Added support for cast(X as double(X,Y))
Added functions to create dynamic column functions.
sql/item_create.h:
Added prototypes
sql/item_func.cc:
Extended cast functions Item_func_signed() and Item_func_unsigned() to work with dynamic types
Added Item_double_typecast()
sql/item_func.h:
Added class Item_double_typecast()
sql/item_strfunc.cc:
Added functions for COLUMN_CREATE(), COLUMN_ADD(), COLUMN_GET() and COLUMN_LIST()
sql/item_strfunc.h:
Added classes for COLUMN_CREATE(), COLUMN_ADD(), COLUMN_GET() and COLUMN_LIST()
sql/item_timefunc.cc:
Added flag argument to str_to_time_with_warn()
Updated Item_char_typecast() to handle result type that may change between calls (for dynamic columns)
Added Item_time_typecast::get_date() to ensure that we cast a datetime to time properly.
sql/item_timefunc.h:
Added get_date() to Item_time_typecast() to allow proper results for casting time to datetime
sql/lex.h:
Added new SQL function names
sql/my_decimal.cc:
Added 'const' to some arguments.
Better error message in case of errors (we now print out the wrong value)
Added my_decimal2int()
sql/my_decimal.h:
Moved some constants to my_decimal_limits.h
Updated prototypes.
Made my_decimal2int() a function as it's rather long (no reason to have it inline)
Added decimal2my_decimal() function.
sql/mysql_priv.h:
Prototypes for new functions
sql/share/errmsg.txt:
New error messages for wrong casts and dynamic columns
sql/sql_acl.cc:
Fixed indentation
sql/sql_base.cc:
Added dynamic_column_error_message()
sql/sql_string.h:
Added reassociate() to move a buffer to be owned by String object.
sql/sql_yacc.yy:
Added syntax for COLUMN_ functions.
sql/time.cc:
Updated str_to_datetime_with_warn() flag argument to same type as other functions
Added conversion flag to str_to_time_with_warn() (Similar to all datetime functions)
Added conversion functions with warnings: double_to_datetime_with_warn() and decimal_to_datetime_with_warn()
strings/decimal.c:
Added 'const' to arguments for some functions.
unittest/mysys/Makefile.am:
Added test for dynamic columns code
(SUBSTRING inside a stored function works too slow).
Background:
- THD classes derives from Query_arena, thus inherits the 'state'
attribute and related operations (is_stmt_prepare() & co).
- Although these operations are available in THD, they must not
be used. THD has its own attribute to point to the active
Query_arena -- stmt_arena.
- So, instead of using thd->is_stmt_prepare(),
thd->stmt_arena->is_stmt_prepare() must be used. This was the root
cause of Bug 60025.
This patch enforces the proper way of calling those operations.
is_stmt_prepare() & co are declared as private operations
in THD (thus, they are hidden from being called on THD instance).
The patch tries to minimize changes in 5.5.
mysql-test/r/explain.result:
fixed results (new item)
mysql-test/r/subselect.result:
fixed results (new item)
mysql-test/r/subselect_no_mat.result:
fixed results (new item)
mysql-test/r/subselect_no_opts.result:
fixed results (new item)
mysql-test/r/subselect_no_semijoin.result:
Fixed results (new item)
mysql-test/suite/pbxt/r/subselect.result:
Fixed results (new item)
mysql-test/t/explain.test:
Fixed results (correct behaviour)
sql/item_cmpfunc.cc:
Pass through for max/min
sql/item_subselect.cc:
moving max/min
sql/item_subselect.h:
moving max/min
sql/mysql_priv.h:
new uncacheble flags added
sql/opt_subselect.cc:
maxmin moved.
sql/opt_subselect.h:
New function for maxmin.
sql/sql_class.h:
debug code
sql/sql_lex.cc:
Fixed flags.
Limit setting fixed.
sql/sql_lex.h:
2 new flags.
sql/sql_select.cc:
Prepare divided on 2 function to be able recollect some info after transformation.
sql/sql_select.h:
Prepare divided on 2 functions.
Both these two bugs happened due to the following problem.
When a view column is referenced in the query an Item_direct_view_ref
object is created that is refers to the Item_field for the column.
All references to the same view column refer to the same Item_field.
Different references can belong to different AND/OR levels and,
as a result, can be included in different Item_equal object.
These Item_equal objects may include different constant objects.
If these constant objects are substituted for the Item_field created
for a view column we have a conflict situation when the second
substitution annuls the first substitution. This leads to
wrong result sets returned by the query. Bug #724942 demonstrates
such an erroneous behaviour.
Test case of the bug #717577 produces wrong result sets because best
equal fields of the multiple equalities built for different OR levels
of the WHERE condition differs. The subsitution for the best equal field
in the second OR branch overwrites the the substitution made for the
first branch.
To avoid such conflicts we have to substitute for the references
to the view columns rather than for the underlying field items.
To make such substitutions possible we have to include into
multiple equalities references to view columns rather than
field items created for such columns.
This patch modifies the Item_equal class to include references
to view columns into multiple equality objects. It also performs
a clean up of the class methods and adds more comments. The methods
of the Item_direct_view_ref class that assist substitutions for
references to view columns has been also added by this patch.
Valgrind warning happens due to early null values check
in Item_func_in::fix_length_and_dec(before item evaluation).
As result null value items with uninitialized values are
placed into array and it leads to valgrind warnings during
value array sorting.
The fix is to check null value after item evaluation, item
is evaluated in in_array::set() method.
mysql-test/r/func_in.result:
test case
mysql-test/t/func_in.test:
test case
sql/item_cmpfunc.cc:
The fix is to check null value after item evaluation.
Analysis:
A query with implicit grouping is one with aggregate functions and
no GROUP BY clause. MariaDB inherits from MySQL an SQL extenstion
that allows mixing aggregate functions with non-aggregate fields.
If a query with such mixed select clause produces an empty result
set, the meaning of aggregate functions is well defined - either
NULL (MIN, MAX, etc.), or 0 (count(*)). However the non-aggregated
fields must also have some value, and the only reasonable value in
the case of empty result is NULL.
The cause of the many wrong results was that if a field is declared
as non-nullable (e.g. because it is a PK or NOT NULL), the semantic
analysis and the optimization phases treat this field as non-nullable,
and generate all related query plan elements based on this assumption.
Later during execution, these incorrectly configured/generated query
plan elements result in a wrong result because the selected fields
are not null due to the not-null assumption during optimization.
Solution:
Detect before the context analysys phase that a query uses implicit
grouping with mixed aggregates/non-aggregates, and set all fields
as nullable. The parser already walks the SELECT clause, and
already sets Item::with_sum_func for Items that reference aggreagate
functions. The patch adds a symmetric Item::with_field so that all
Items that reference an Item_field are marked during their
construction at parse time in the same way as with aggregate function
use.
many changes:
* NOT_FIXED_DEC now create hires fields, not old ones.
As a result, temp tables preserve microseconds (on DISTINCT, GROUP BY)
* I_S tables force decimals=0 on temporal types (backward compatibility)
* Item_func_coalesce calculates decimals for temporal types
* no precision for TIME/DATETIME in CAST means 0, not NOT_FIXED_DEC
* addtime/timediff calculate decimals from arguments (not NOT_FIXED_DEC)
sql/field.h:
NOT_FIXED_DEC now create hires fields, not old ones
sql/item.h:
force decimals=0 for I_S tables
sql/item_cmpfunc.cc:
Item_func_coalesce calculates decimals for temporal types
sql/item_create.cc:
no precision for TIME/DATETIME in CAST means 0, not NOT_FIXED_DEC
sql/item_timefunc.cc:
addtime calculates decimals from arguments (not NOT_FIXED_DEC)
sql/item_timefunc.h:
timediff calculates decimals from arguments (not NOT_FIXED_DEC)
sql/field.cc:
initialize ltime completely
sql/filesort.cc:
don't pack MYSQL_TIME if it's not initialized
(safe here, but valgrind complains)
sql/item_cmpfunc.cc:
don't pack MYSQL_TIME if it's not initialized
(safe here, but valgrind complains)
sql/item_timefunc.cc:
don't check MYSQL_TIME members if it's uninitialized
(safe here, but valgrind complains)
sql/time.cc:
use c_ptr_safe() instead of c_ptr()
(make valgrind happy)
and collateral changes.
* introduce my_hrtime_t, my_timediff_t, and conversion macros
* inroduce TIME_RESULT, but it can only be returned from Item::cmp_type(),
never from Item::result_type()
* pack_time/unpack_time function for "packed" representation of
MYSQL_TIME in a longlong that can be compared
* ADDTIME()/SUBTIME()/+- INTERVAL now work with TIME values
* numbers aren't quoted in EXPLAIN EXTENDED
* new column I_S.COLUMNS.DATETIME_PRECISION
* date/time values are compares to anything as date/time, not as strings or numbers.
* old timestamp(X) is no longer supported
* MYSQL_TIME to string conversion functions take precision as an argument
* unified the warnings from Field_timestamp/datetime/time/date/newdate store methods
* Field_timestamp_hires, Field_datetime_hires, Field_time_hires
* Field_temporal
* Lazy_string class to pass a value (string, number, time) polymorphically down the stack
* make_truncated_value_warning and Field::set_datetime_warning use Lazy_string as an argument, removed char*/int/double variants
* removed Field::can_be_compared_as_longlong(). Use Field::cmp_type() == INT_RESULT instead
* introduced Item::cmp_result() instead of Item::is_datetime() and Item::result_as_longlong()
* in many cases date/time types are treated like other types, not as special cases
* greatly simplified Arg_comparator (regarding date/time/year code)
* SEC_TO_TIME is real function, not integer.
* microsecond precision in NOW, CURTIME, etc
* Item_temporal. All items derived from it only provide get_date, but no val* methods
* replication of NOW(6)
* Protocol::store(time) now takes the precision as an argument
* @@TIMESTAMP is a double
client/mysqlbinlog.cc:
remove unneded casts
include/my_sys.h:
introduce my_hrtime_t, my_timediff_t, and conversion macros
include/my_time.h:
pack_time/unpack_time, etc.
convenience functions to work with MYSQL_TIME::second_part
libmysql/libmysql.c:
str_to_time() is gone. str_to_datetime() does it now.
my_TIME_to_str() takes the precision as an argument
mysql-test/include/ps_conv.inc:
time is not equal to datetime anymore
mysql-test/r/distinct.result:
a test for an old MySQL bug
mysql-test/r/explain.result:
numbers aren't quoted in EXPLAIN EXTENDED
mysql-test/r/func_default.result:
numbers aren't quoted in EXPLAIN EXTENDED
mysql-test/r/func_sapdb.result:
when decimals=NOT_FIXED_DEC it means "not fixed" indeed
mysql-test/r/func_test.result:
numbers aren't quoted in EXPLAIN EXTENDED
mysql-test/r/func_time.result:
ADDTIME()/SUBTIME()/+- INTERVAL now work with TIME values
mysql-test/r/having.result:
numbers aren't quoted in EXPLAIN EXTENDED
mysql-test/r/information_schema.result:
new column I_S.COLUMNS.DATETIME_PRECISION
mysql-test/r/join_outer.result:
numbers aren't quoted in EXPLAIN EXTENDED
mysql-test/r/metadata.result:
TIMESTAMP no longer has zerofill flag
mysql-test/r/range.result:
invalid datetime is not compared with as a string
mysql-test/r/select.result:
NO_ZERO_IN_DATE, etc only affect storage - according to the manual
numbers aren't quoted in EXPLAIN EXTENDED
mysql-test/r/subselect.result:
numbers aren't quoted in EXPLAIN EXTENDED
mysql-test/r/sysdate_is_now.result:
when decimals=NOT_FIXED_DEC it means "not fixed" indeed
mysql-test/r/type_blob.result:
TIMESTAMP(N) is not deprecated
mysql-test/r/type_timestamp.result:
old TIMESTAMP(X) semantics is not supported anymore
mysql-test/r/union.result:
numbers aren't quoted in EXPLAIN EXTENDED
mysql-test/r/varbinary.result:
numbers aren't quoted in EXPLAIN EXTENDED
mysql-test/t/distinct.test:
test for an old MySQL bug
mysql-test/t/func_time.test:
+- INTERVAL now works with TIME values
mysql-test/t/select.test:
typo
mysql-test/t/subselect.test:
only one error per statement, please
mysql-test/t/system_mysql_db_fix40123.test:
old timestamp(X) is no longer supported
mysql-test/t/system_mysql_db_fix50030.test:
old timestamp(X) is no longer supported
mysql-test/t/system_mysql_db_fix50117.test:
old timestamp(X) is no longer supported
mysql-test/t/type_blob.test:
old timestamp(X) is no longer supported
mysql-test/t/type_timestamp.test:
old timestamp(X) is no longer supported
mysys/my_getsystime.c:
functions to get the time with microsecond precision
mysys/my_init.c:
move the my_getsystime.c initialization code to my_getsystime.c
mysys/my_static.c:
no need to make these variables extern
mysys/my_static.h:
no need to make these variables extern
scripts/mysql_system_tables.sql:
old timestamp(X) is no longer supported
scripts/mysql_system_tables_fix.sql:
old timestamp(X) is no longer supported
scripts/mysqlhotcopy.sh:
old timestamp(X) is no longer supported
sql-common/my_time.c:
* call str_to_time from str_to_datetime, as appropriate
* date/time to string conversions take precision as an argument
* number_to_time()
* TIME_to_double()
* pack_time() and unpack_time()
sql/event_data_objects.cc:
cast is not needed
my_datetime_to_str() takes precision as an argument
sql/event_db_repository.cc:
avoid dangerous downcast (because the pointer is
not always Field_timestamp, see events_1.test)
sql/event_queue.cc:
avoid silly double-work for cond_wait
(having an endpoint of wait, subtract the current time to get the timeout,
and use set_timespec() macro to fill in struct timespec, by adding the current
time to the timeout)
sql/field.cc:
* remove virtual Field::get_time(), everyone should use only Field::get_date()
* remove lots of #ifdef WORDS_BIGENDIAN
* unified the warnings from Field_timestamp/datetime/time/date/newdate store methods
* Field_timestamp_hires, Field_datetime_hires, Field_time_hires
* Field_temporal
* make_truncated_value_warning and Field::set_datetime_warning use Lazy_string as an argument, removed char*/int/double variants
sql/field.h:
* remove virtual Field::get_time(), everyone should use only Field::get_date()
* remove lots of #ifdef WORDS_BIGENDIAN
* unified the warnings from Field_timestamp/datetime/time/date/newdate store methods
* Field_timestamp_hires, Field_datetime_hires, Field_time_hires
* Field_temporal
* make_truncated_value_warning and Field::set_datetime_warning use Lazy_string as an argument, removed char*/int/double variants
* removed Field::can_be_compared_as_longlong(). Use Field::cmp_type() == INT_RESULT instead
sql/filesort.cc:
TIME_RESULT, cmp_time()
sql/item.cc:
* numbers aren't quoted in EXPLAIN EXTENDED
* Item::cmp_result() instead of Item::is_datetime() and Item::result_as_longlong()
* virtual Item::get_time() is gone
* Item_param::field_type() is set correctly
* Item_datetime, for a datetime constant
* time to anything is compared as a time
* Item_cache::print() prints the value is available
* bug fixed in Item_cache_int::val_str()
sql/item.h:
* Item::print_value(), to be used from Item_xxx::print() when needed
* Item::cmp_result() instead of Item::is_datetime() and Item::result_as_longlong()
* virtual Item::get_time() is gone
* Item_datetime, for a datetime constant
* better default for cast_to_int_type()
* Item_cache objects now *always* have the field_type() set
sql/item_cmpfunc.cc:
* get_year_value, get_time_value are gone. get_datetime_value does it all
* get_value_a_func, get_value_b_func are gone
* can_compare_as_dates() is gone too, TIME_RESULT is used instead
* cmp_type() instead or result_type() when doing a comparison
* compare_datetime and compate_e_datetime in the comparator_matrix, is_nulls_eq is gone
* Item::cmp_result() instead of Item::is_datetime() and Item::result_as_longlong()
sql/item_cmpfunc.h:
greatly simplified Arg_comparator
sql/item_create.cc:
* fix a bug in error messages in CAST
sql/item_func.cc:
Item::cmp_result() instead of Item::is_datetime() and Item::result_as_longlong()
mention all possibitiles in switch over Item_result values, or use default:
sql/item_row.h:
overwrite the default cmp_type() for Item_row,
as no MYSQL_TYPE_xxx value corresponds to ROW_RESULT
sql/item_timefunc.cc:
rewrite make_datetime to support precision argument
SEC_TO_TIME is real function, not integer.
many functions that returned temporal values had duplicate code in val_* methods,
some of them did not have get_date() which resulted in unnecessary date->str->date conversions.
Now they all are derived from Item_temporal_func and *only* provide get_date, not val* methods.
many fixes to set decimals (datetime precision) correctly.
sql/item_timefunc.h:
SEC_TO_TIME is real function, not integer.
many functions that returned temporal values had duplicate code in val_* methods,
some of them did not have get_date() which resulted in unnecessary date->str->date conversions.
Now they all are derived from Item_temporal_func and *only* provide get_date, not val* methods.
many fixes to set decimals (datetime precision) correctly.
sql/log_event.cc:
replication of NOW(6)
sql/log_event.h:
replication of NOW(6)
sql/mysql_priv.h:
Lazy_string class to pass a value (string, number, time) polymorphically down the stack.
make_truncated_value_warning() that uses it.
sql/mysqld.cc:
datetime in Arg_comparator::comparator_matrix
sql/opt_range.cc:
cleanup: don't disable warnings before calling save_in_field_no_warnings()
sql/protocol.cc:
Protocol::store(time) now takes the precision as an argument
sql/protocol.h:
Protocol::store(time) now takes the precision as an argument
sql/rpl_rli.cc:
small cleanup
sql/set_var.cc:
SET TIMESTAMP=double
sql/set_var.h:
@@TIMESTAMP is a double
sql/share/errmsg.txt:
precision and scale are unsigned
sql/slave.cc:
replication of NOW(6)
sql/sp_head.cc:
cleanup
sql/sql_class.cc:
support for NOW(6)
sql/sql_class.h:
support for NOW(6)
sql/sql_insert.cc:
support for NOW(6)
sql/sql_select.cc:
use item->cmp_type().
move a comment where it belongs
sql/sql_show.cc:
new column I_S.COLUMNS.DATETIME_PRECISION
sql/sql_yacc.yy:
TIME(X), DATETIME(X), cast, NOW(X), CURTIME(X), etc
sql/time.cc:
fix date_add_interval() to support MYSQL_TIMESTAMP_TIME argument
storage/myisam/ha_myisam.cc:
TIMESTAMP no longer carries ZEROFIELD flag, still we keep MYI file compatible.
strings/my_vsnprintf.c:
warnings
tests/mysql_client_test.c:
old timestamp(X) does not work anymore
datetime is no longer equal to time
Problem: in case of string CASE/WHEN arguments with different
character sets, Item_func_case::find_item() called comparator
cmp_items[x] on mixed character set Items, so a 8-bit value could
be errouneously referenced to as being utf16/utf32 value,
which led to crash on DBUG_ASSERT() because of wrong value length.
This was wrong, as string comparator expects arguments in the same
character set.
Fix: modify Item_func_case's argument list after calling
agg_arg_charsets_for_comparison() - put the Items in "agg" array
back to "args", because some of the Items in the "agg" array might
have been changed to character set converters:
- to Item_func_conv_charset for non-constant items
- to Item_string for constant items
In other words, perform the same substitution which is done in
all other operations string comparison or string result operations:
Replace
CASE latin1_item WHEN utf16_item THEN ... END
to
CASE CONVERT(latin1_item USING utf16) WHEN utf16_item THEN ... END
Replace
CASE utf16_item WHEN latin1_item THEN ... END
to
CASE utf16_item WHEN CONVERT(latin1_item USING utf16) THEN ... END
@ mysql-test/r/ctype_utf16.result
@ mysql-test/r/ctype_utf32.result
@ mysql-test/t/ctype_utf16.test
@ mysql-test/t/ctype_utf32.test
Adding tests
@ sql/item_cmpfunc.cc
Put "agg" back to "args".
@ sql/sql_string.cc
Backporting a fix for String::set_or_copy_aligned() from 5.6,
for better test coverage:
"SELECT _utf16 0x61" should expand the string to 0x0061 rather
than to 0x000061.
This fix was made in 5.6 under terms of "WL#4616 Implement UTF16-LE".
- Fixed some issues with partitions and connection_string, which also fixed lp:716890 "Pre- and post-recovery crash in Aria"
- Fixed wrong assert in Aria
Now need to merge with latest xtradb before pushing
sql/ha_partition.cc:
Ensure that m_ordered_rec_buffer is not freed before close.
sql/mysqld.cc:
Changed to use opt_stack_trace instead of opt_pstack.
Removed references to pstack
sql/partition_element.h:
Ensure that connect_string is initialized
storage/maria/ma_key_recover.c:
Fixed wrong assert
Problem:
IF() did not copy collation derivation and repertoire from
an argument if the opposite argument was NULL:
IF(cond, res1, NULL)
IF(cond, NULL, res2)
only CHARSET_INFO pointer was copied.
This resulted in illegal mix of collations error.
Fix:
copy all collation parameters from the non-NULL argument:
CHARSET_INFO pointer, derivation, repertoire.
with the test case added by this patch.
The bug cannot be reproduced with the same test case for the main
5.3 tree because the backported fix for bug 59696 masks the
problem that causes the crash in the mentioned test case. It's not
clear weather this fix masks this problem in all possible cases.
Anyway the patch for bug 698882 introduced some inconsistent data
structures that could contain indirect references to deleted object.
It happened when two Item_equal objects were merged and the Item_field
list of the second object was joined to such list of the first object.
This operation required adjustment of the backward pointers in
Item fields from the joined list. However the adjustment was missing
and this caused crashes in the tree for mwl#128.
Now the backward pointers are set only when Item_equal items are
completely built and are not changed anymore.
ZERO
When dates are represented internally as strings, i.e. when a string constant
is compared to a date value, both values are converted to long integers,
ostensibly for fast comparisons. DATE typed integer values are converted to
DATETIME by multiplying by 1,000,000 (each digit pair representing hour,
minute and second, respectively). But the mechanism did not distuinguish
cached INTEGER values, already in correct format, from newly converted
strings.
Fixed by marking the INTEGER cache as being of DATETIME format.
Made sure that the optimal fields are used by TABLE_REF objects
when building index access keys to joined tables.
Fixed a bug in the template function that sorts the elements of
a list using the bubble sort algorithm. The bug caused poor
performance of the function. Also added an optimization that
skips comparison with the most heavy elements that has been
already properly placed in the list.
Made the comparison of the fields belonging to the same Item_equal
more granular: fields belonging to the same table are also ordered
according to some rules.
get_year_value() contains code to convert 2-digits year to
4-digits. The fix for Bug#49910 added a check on the size of
the underlying field so that this conversion is not done for
YEAR(4) values. (Since otherwise one would convert invalid
YEAR(4) values to valid ones.)
The existing check does not work when Item_cache is used, since
it is not detected when the cache is based on a Field. The
reported change in behavior is due to Bug#58030 which added
extra cached items in min/max computations.
The elegant solution would be to implement
Item_cache::real_item() to return the underlying Item.
However, some side effects are observed (change in explain
output) that indicates that such a change is not straight-
forward, and definitely not appropriate for an MRU.
Instead, a Item_cache::field() method has been added in order
to get access to the underlying field. (This field() method
eliminates the need for Item_cache::eq_def() used in
test_if_ref(), but in order to limit the scope of this fix,
that code has been left as is.)
mysql-test/r/type_year.result:
Added test case for Bug#59211.
mysql-test/t/type_year.test:
Added test case for Bug#59211.
sql/item.h:
Added function Item_cache::field() to get access to the
underlying Field of a cached field Value.
sql/item_cmpfunc.cc:
Also check underlying fields of Item_cache, not just Item_Field,
when checking whether the value is of type YEAR(4) or not.
Fix: copy my_decimal by value, to avoid dangling pointers.
mysql-test/r/func_math.result:
New test case.
mysql-test/t/func_math.test:
New test case.
sql/item_cmpfunc.cc:
No need to call fix_buffer_pointer() anymore.
sql/item_func.cc:
Copy my_decimal by value, to avoid dangling pointers.
sql/my_decimal.h:
Implement proper copy constructor and assignment operator for my_decimal.
sql/sql_analyse.cc:
No need to call fix_buffer_pointer() anymore.
strings/decimal.c:
Remove #line directive: it messes up TAGS and it confuses gdb when debugging.
Item_equal::val_int() checked for NULL-values by checking Item::null_value
*before* the respective ::store_value() and ::cmp(Item*) metods where called.
As Item::null_value is set by these metods, the value of 'null_value'
is not valid until *after* ::store_value() or ::cmp() has
been called for the Item object.
Fix is to swap order of ::store_value()/::cmp() and checking of Item::null_value.
This pattern is widely used other places inside item_cmpfunc.cc .
- Removed files specific to compiling on OS/2
- Removed files specific to SCO Unix packaging
- Removed "libmysqld/copyright", text is included in documentation
- Removed LaTeX headers for NDB Doxygen documentation
- Removed obsolete NDB files
- Removed "mkisofs" binaries
- Removed the "cvs2cl.pl" script
- Changed a few GPL texts to use "program" instead of "library"
--Bug#52157 various crashes and assertions with multi-table update, stored function
--Bug#54475 improper error handling causes cascading crashing failures in innodb/ndb
--Bug#57703 create view cause Assertion failed: 0, file .\item_subselect.cc, line 846
--Bug#57352 valgrind warnings when creating view
--Recently discovered problem when a nested materialized derived table is used
before being populated and it leads to incorrect result
We have several modes when we should disable subquery evaluation.
The reasons for disabling are different. It could be
uselessness of the evaluation as in case of 'CREATE VIEW'
or 'PREPARE stmt', or we should disable subquery evaluation
if tables are not locked yet as it happens in bug#54475, or
too early evaluation of subqueries can lead to wrong result
as it happened in Bug#19077.
Main problem is that if subquery items are treated as const
they are evaluated in ::fix_fields(), ::fix_length_and_dec()
of the parental items as a lot of these methods have
Item::val_...() calls inside.
We have to make subqueries non-const to prevent unnecessary
subquery evaluation. At the moment we have different methods
for this. Here is a list of these modes:
1. PREPARE stmt;
We use UNCACHEABLE_PREPARE flag.
It is set during parsing in sql_parse.cc, mysql_new_select() for
each SELECT_LEX object and cleared at the end of PREPARE in
sql_prepare.cc, init_stmt_after_parse(). If this flag is set
subquery becomes non-const and evaluation does not happen.
2. CREATE|ALTER VIEW, SHOW CREATE VIEW, I_S tables which
process FRM files
We use LEX::view_prepare_mode field. We set it before
view preparation and check this flag in
::fix_fields(), ::fix_length_and_dec().
Some bugs are fixed using this approach,
some are not(Bug#57352, Bug#57703). The problem here is
that we have a lot of ::fix_fields(), ::fix_length_and_dec()
where we use Item::val_...() calls for const items.
3. Derived tables with subquery = wrong result(Bug19077)
The reason of this bug is too early subquery evaluation.
It was fixed by adding Item::with_subselect field
The check of this field in appropriate places prevents
const item evaluation if the item have subquery.
The fix for Bug19077 fixes only the problem with
convert_constant_item() function and does not cover
other places(::fix_fields(), ::fix_length_and_dec() again)
where subqueries could be evaluated.
Example:
CREATE TABLE t1 (i INT, j BIGINT);
INSERT INTO t1 VALUES (1, 2), (2, 2), (3, 2);
SELECT * FROM (SELECT MIN(i) FROM t1
WHERE j = SUBSTRING('12', (SELECT * FROM (SELECT MIN(j) FROM t1) t2))) t3;
DROP TABLE t1;
4. Derived tables with subquery where subquery
is evaluated before table locking(Bug#54475, Bug#52157)
Suggested solution is following:
-Introduce new field LEX::context_analysis_only with the following
possible flags:
#define CONTEXT_ANALYSIS_ONLY_PREPARE 1
#define CONTEXT_ANALYSIS_ONLY_VIEW 2
#define CONTEXT_ANALYSIS_ONLY_DERIVED 4
-Set/clean these flags when we perform
context analysis operation
-Item_subselect::const_item() returns
result depending on LEX::context_analysis_only.
If context_analysis_only is set then we return
FALSE that means that subquery is non-const.
As all subquery types are wrapped by Item_subselect
it allow as to make subquery non-const when
it's necessary.
mysql-test/r/derived.result:
test case
mysql-test/r/multi_update.result:
test case
mysql-test/r/view.result:
test case
mysql-test/suite/innodb/r/innodb_multi_update.result:
test case
mysql-test/suite/innodb/t/innodb_multi_update.test:
test case
mysql-test/suite/innodb_plugin/r/innodb_multi_update.result:
test case
mysql-test/suite/innodb_plugin/t/innodb_multi_update.test:
test case
mysql-test/t/derived.test:
test case
mysql-test/t/multi_update.test:
test case
mysql-test/t/view.test:
test case
sql/item.cc:
--removed unnecessary code
sql/item_cmpfunc.cc:
--removed unnecessary checks
--THD::is_context_analysis_only() is replaced with LEX::is_ps_or_view_context_analysis()
sql/item_func.cc:
--refactored context analysis checks
sql/item_row.cc:
--removed unnecessary checks
sql/item_subselect.cc:
--removed unnecessary code
--added DBUG_ASSERT into Item_subselect::exec()
which asserts that subquery execution can not happen
if LEX::context_analysis_only is set, i.e. at context
analysis stage.
--Item_subselect::const_item()
Return FALSE if LEX::context_analysis_only is set.
It prevents subquery evaluation in ::fix_fields &
::fix_length_and_dec at context analysis stage.
sql/item_subselect.h:
--removed unnecessary code
sql/mysql_priv.h:
--Added new set of flags.
sql/sql_class.h:
--removed unnecessary code
sql/sql_derived.cc:
--added LEX::context_analysis_only analysis intialization/cleanup
sql/sql_lex.cc:
--init LEX::context_analysis_only field
sql/sql_lex.h:
--New LEX::context_analysis_only field
sql/sql_parse.cc:
--removed unnecessary code
sql/sql_prepare.cc:
--removed unnecessary code
--added LEX::context_analysis_only analysis intialization/cleanup
sql/sql_select.cc:
--refactored context analysis checks
sql/sql_show.cc:
--added LEX::context_analysis_only analysis intialization/cleanup
sql/sql_view.cc:
--added LEX::context_analysis_only analysis intialization/cleanup
Fixed compiler warning
mysql-test/r/named_pipe.result:
Fixed test results for windows builds
mysql-test/r/shm.result:
Fixed test results for windows builds
sql/item_cmpfunc.cc:
Fixed compiler warning about uninitialized "first"
- Fixed problem with oqgraph and 'make dist'
Note that after this merge we have a problem show in join_outer where we examine too many rows in one specific case (related to BUG#57024).
This will be fixed when mwl#128 is merged into 5.3.
ESCAPE argument might be empty string. It leads
to server crash under some circumstances.
The fix:
-added check if ESCAPE argument result is not empty string
mysql-test/r/ctype_latin1.result:
test case
mysql-test/t/ctype_latin1.test:
test case
sql/item_cmpfunc.cc:
-added check if ESCAPE argument result is not empty string
Merge 5.3-mwl89 into 5.3 main.
There is one remaining test failure in this merge:
innodb_mysql_lock2. All other tests have been checked to
deliver the same results/explains as 5.3-mwl89, including
the few remaining wrong results.
