- Removed not used variables and functions
- Added #ifdef around code that is not used
- Renamed variables and functions to avoid conflicts
- Removed some not used arguments
Fixed some class/struct warnings in ndb
Added define IS_LONGDATA() to simplify code in libmysql.c
I did run gcov on the changes and added 'purecov' comments on almost all lines that was not just variable name changes
Blocked evaluation of constant objects of the classes
Item_func_is_null and Item_is_not_null_test at the
prepare phase in the cases when the objects used subqueries.
(Mostly in DBUG_PRINT() and unused arguments)
Fixed bug in query cache when used with traceing (--with-debug)
Fixed memory leak in mysqldump
Removed warnings from mysqltest scripts (replaced -- with #)
The problem was that some functions (namely IN() starting with 4.1, and
CHAR() starting with 5.0) were returning NULL in certain conditions,
while they didn't set their maybe_null flag. Because of that there could
be some problems with 'IS NULL' check, and statements that depend on the
function value domain, like CREATE TABLE t1 SELECT 1 IN (2, NULL);.
The fix is to set maybe_null correctly.
Evaluate "NULL IN (SELECT ...)" in a special way: Disable pushed-down
conditions and their "consequences":
= Do full table scans instead of unique_[index_subquery] lookups.
= Change appropriate "ref_or_null" accesses to full table scans in
subquery's joins.
Also cache value of NULL IN (SELECT ...) if the SELECT is not correlated
wrt any upper select.
account predicates that become sargable after reading const tables.
In some cases this resulted in choosing non-optimal execution plans.
Now info of such potentially saragable predicates is saved in
an array and after reading const tables we check whether this
predicates has become saragable.
Removed changes to the Item_func_between::fix_length_and_dec() made in the fix for bug#16377
query_cache.result:
Corrected a test case after removing a fix for bug#16377
Corrected test case after removal of fix for bug#16377
type_date.test:
Corrected test case after removal of fix for bug#16377
item_cmpfunc.cc:
Removed changes to the agg_cmp_type() made in the for bug#16377
equal constant under any circumstances.
In fact this substitution can be allowed if the field is
not of a type string or if the field reference serves as
an argument of a comparison predicate.
A date can be represented as an int (like 20060101) and as a string (like
"2006.01.01"). When a DATE/TIME field is compared in one SELECT against both
representations the constant propagation mechanism leads to comparison
of DATE as a string and DATE as an int. In this example it compares 2006 and
20060101 integers. Obviously it fails comparison although they represents the
same date.
Now the Item_bool_func2::fix_length_and_dec() function sets the comparison
context for items being compared. I.e. if items compared as strings the
comparison context is STRING.
The constant propagation mechanism now doesn't mix items used in different
comparison contexts. The context check is done in the
Item_field::equal_fields_propagator() and in the change_cond_ref_to_const()
functions.
Also the better fix for bug 21159 is introduced.
This bug is a side-effect of bug fix#16377. NOW() is optimized in
BETWEEN to integer constants to speed up query execution. When view is being
created it saves already modified query and thus becomes wrong.
The agg_cmp_type() function now substitutes constant result DATE/TIME functions
for their results only if the current query isn't CREATE VIEW or SHOW CREATE
VIEW.
Two functions have different ideas of what a string should look like;
one of them reads memory it assumes the other one may have written.
And "if you assume ..."
We now use a more defensive variety of the assuming function, this fixes
a warning thrown by the valgrind tool.
In some functions dealing with strings and character sets, the wrong
pointers were saved for restoration in THD::rollback_item_tree_changes().
This could potentially cause random corruption or crashes.
Fixed by passing the original Item ** locations, not local stack copies.
Also remove unnecessary use of default arguments.
Added test case for bug#18759 Incorrect string to numeric conversion.
select.test:
Added test case for bug#18759 Incorrect string to numeric conversion.
item_cmpfunc.cc:
Cleanup after fix for bug#18360 removal
Fix for bug#16716 for --ps-protocol mode.
item_cmpfunc.cc:
Fix for a memory allocation/freeing problem in agg_cmp_type() after fix
for bug#16377. Few language corrections.
can lead to a wrong result.
All date/time functions has the STRING result type thus their results are
compared as strings. The string date representation allows a user to skip
some of leading zeros. This can lead to wrong comparison result if a date/time
function result is compared to such a string constant.
The idea behind this bug fix is to compare results of date/time functions
and data/time constants as ints, because that date/time representation is
more exact. To achieve this the agg_cmp_type() is changed to take in the
account that a date/time field or an date/time item should be compared
as ints.
This bug fix is partially back ported from 5.0.
The agg_cmp_type() function now accepts THD as one of parameters.
In addition, it now checks if a date/time field/function is present in the
list. If so, it tries to coerce all constants to INT to make date/time
comparison return correct result. The field for the constant coercion is
taken from the Item_field or constructed from the Item_func. In latter case
the constructed field will be freed after conversion of all constant items.
Otherwise the result is same as before - aggregated with help of the
item_cmp_type() function.
From the Item_func_between::fix_length_and_dec() function removed the part
which was converting date/time constants to int if possible. Now this is
done by the agg_cmp_type() function.
The new function result_as_longlong() is added to the Item class.
It indicates that the item is a date/time item and result of it can be
compared as int. Such items are date/time fields/functions.
Correct val_int() methods are implemented for classes Item_date_typecast,
Item_func_makedate, Item_time_typecast, Item_datetime_typecast. All these
classes are derived from Item_str_func and Item_str_func::val_int() converts
its string value to int without regard to the date/time type of these items.
Arg_comparator::set_compare_func() and Arg_comparator::set_cmp_func()
functions are changed to substitute result type of an item with the INT_RESULT
if the item is a date/time item and another item is a constant. This is done
to get a correct result of comparisons like date_time_function() = string_constant.
The IN() function uses agg_cmp_type() to aggregate all types of its arguments
to find out some common type for comparisons. In this particular case the
char() and the int was aggregated to double because char() can contain values
like '1.5'. But all strings which do not start from a digit are converted to
0. thus 'a' and 'z' become equal.
This behaviour is reasonable when all function arguments are constants. But
when there is a field or an expression this can lead to false comparisons. In
this case it makes more sense to coerce constants to the type of the field
argument.
The agg_cmp_type() function now aggregates types of constant and non-constant
items separately. If some non-constant items will be found then their
aggregated type will be returned. Thus after the aggregation constants will be
coerced to the aggregated type.
This bug was introduced when the patch resolving the
performance problem 17164 was applied. As a result
of that modification the not_null_tables attributes
were calculated incorrectly for constant OR conditions.
This triggered invalid conversion of outer joins into
inner joins.
The convert_constant_item() function converts constant items to ints on
prepare phase to optimize execution speed. In this case it tries to evaluate
subselect which contains a derived table and is contained in a derived table.
All derived tables are filled only after all derived tables are prepared.
So evaluation of subselect with derived table at the prepare phase will
return a wrong result.
A new flag with_subselect is added to the Item class. It indicates that
expression which this item represents is a subselect or contains a subselect.
It is set to 0 by default. It is set to 1 in the Item_subselect constructor
for subselects.
For Item_func and Item_cond derived classes it is set after fixing any argument
in Item_func::fix_fields() and Item_cond::fix_fields accordingly.
The convert_constant_item() function now doesn't convert a constant item
if the with_subselect flag set in it.
If the second or the third argument of a BETWEEN predicate was
a constant expression, like '2005.09.01' - INTERVAL 6 MONTH,
while the other two arguments were fields then the predicate
was evaluated incorrectly and the query returned a wrong
result set.
The bug was introduced in 5.0.17 when in the fix for 12612.
The function agg_cmp_type in item_cmpfunc.cc neglected the fact that
the first argument in a BETWEEN/IN predicate could be a field of a view.
As a result in the case when the retrieved table was hidden by a view
over it and the arguments in the BETWEEN/IN predicates are of
the date/time type the function did not perform conversion of
the constant arguments to the same format as the first field argument.
If formats of the arguments differed it caused wrong a evaluation of
the predicates.
Multiple equalities were not adjusted after reading constant tables.
It resulted in neglecting good index based methods that could be
used to access of other tables.
If the WHERE condition of a query contained an ORed FALSE term
then the set of tables whose rows cannot serve for null complements
in outer joins was determined incorrectly. It resulted in blocking
possible conversions of outer joins into joins for such queries.
When the Item_cond::fix_fields() function reduces cond tree, it in loop
scans it's own list and when it founds Item_cond with same function (AND
or OR) it does next things: 1) replaces that item with item's list. 2)
empties item's list. Due to this operation is done twice - for update and
for view, at the update phase cond's list of lower view is already empty.
Empty list returns ref to itself, thus making endless loop by replacing
list with itself, emptying, replacing again and so on. This results in
server hung up.
To the Item_cond::fix_fields() function added check that ensures that
list being replaced with isn't empty.
The Item_func_if::fix_length_and_dec() function when calculating length of
result doesn't take into account unsigned_flag. But it is taken when
calculating length of temporary field. This result in creating field that
shorter than needed. Due to this, in the reported query 40.0 converted to 9.99.
The function Item_func_if::fix_length_and_dec() now adds 1 to the max_length if
the unsigned_flag isn't set.
select result
Item equal objects are employed only at the optimize phase. Usually they are not
supposed to be evaluated. Yet in some cases we call the method val_int() for
them. Here we have to take care of restricting the predicate such an object
represents f1=f2= ...=fn to the projection of known fields fi1=...=fik.
Added a check for field's table being const in Item_equal::val_int().
If the field's table is not const val_int() just skips that field when
evaluating Item_equal.
Bad examples of usage of a string with its length fixed.
The incorrect length in the trigger file configuration descriptor
fixed (BUG#14090).
A hook for unknown keys added to the parser to support old .TRG files.
Invalid date like 2000-02-32 wasn't converted to int, which lead to not
using index and comparison with field as astring, which results in slow
query execution.
convert_constatn_item() and get_mm_leaf() now forces MODE_INVALID_DATES to
allow such conversion.
ESCAPE has length of 1 if specified and sql_mode is NO_BACKSLASH_ESCAPES
or has length of 0 or 1 in every other situation.
(approved patch applied on a up-to-date tree re-commit)
index doesn't return correct result
item_cmpfunc.cc:
Use charset of LIKE to decide whether
to use 8bit or Unicode "escape" value.
But use charset of "escape" to scan escape character.
strings/ctype-xxx.c:
We cannot reduce "end" pointer using charpos(),
because of possible escape characters in the string.
Limit the loop using count of written characters instead.
ctype_like_escape.inc:
new file
mysql-test/t/ctype_xxx:
mysql-test/r/ctype_xxx:
Adding test case.
Post merge changes
sql_yacc.yy:
Post merge changes
sql_select.cc:
Fixed bugs #12101, #12102: wrong calculation of not_null_tables()
for some expressions (post merge changes).
The function add_key_fields() is modified. There cannot be NOT before
BETWEEN/IN anymore. Rather Item_func_between/in objects can represent
now [NOT]BETWEEN/IN expressions.
Fixed bugs #12101, #12102: wrong calculation of not_null_tables()
for some expressions.
The classes Item_func_between, Item_func_if, Item_func_in are modified.
Item_func_between/in objects can represent now [NOT]BETWEEN/IN expressions.
The class Item_func_opt_neg is added to factor out the functionality
common for the modified classes Item_func_between and Item_func_in.
item_cmpfunc.cc:
Fixed bugs #12101, #12102: wrong calculation of not_null_tables()
for some expressions.
Added Item_func_between::fix_fields(), Item_func_if::fix_fields(),
Item_func_in::fix_fields(). They correct generic calculation of
the not_null_tables attribute when it is needed.
Modified Item_func_between::val_int(), Item_func_in::val_int().
opt_range.cc:
Fixed bugs #12101, #12102: wrong calculation of not_null_tables()
for some expressions.
The function get_mm_tree() is modified. There cannot be NOT before
BETWEEN/IN anymore. Rather Item_func_between/in objects can represent
now [NOT]BETWEEN/IN expressions.
sql_yacc.yy:
Fixed bugs #12101, #12102: wrong calculation of not_null_tables()
for some expressions.
Item_func_between/in objects can represent now [NOT]BETWEEN/IN expresions.
join_outer.result:
Fixed some testcases results (bugs #12101, #12102)
join_outer.test:
Added testcases for bugs #12101, #12102
adding test case.
item_cmpfunc.cc:
Bug#12611
ESCAPE + LIKE do not work when the escape char is a multibyte one
Additional fix for 8bit character sets:
escape character must be converted into
operation character set.
- current_arena to stmt_arena: the thread may have more than one
'current' arenas: one for runtime data, and one for the parsed
tree of a statement. Only one of them is active at any moment.
- set_item_arena -> set_query_arena, because Item_arena was renamed to
Query_arena a while ago
- set_n_backup_item_arena -> set_n_backup_active_arena;
the active arena is the arena thd->mem_root and thd->free_list
are currently pointing at.
- restore_backup_item_arena -> restore_active_arena (with the same
rationale)
- change_arena_if_needed -> activate_stmt_arena_if_needed; this
method sets thd->stmt_arena active if it's not done yet.
item_cmpfunc.cc:
Pass unicode value as "escape" argument to my_wildcmp
if a multibyte character set is used.
For single byte character set nothing has changed:
native (non-unicode) character code is still passed.
ctype_utf8.result, ctype_utf8.test:
adding test case
Added a test case for bug #12392.
item_cmpfunc.cc:
Fixed bug #12392.
Missing handling of rows containing NULL components
when evaluating IN predicates caused a crash.
Changed defaults option --instance to --defaults-group-suffix
Changed option handling to allow --defaults-file, --defaults-extra-file and --defaults-group-suffix to be given in any order
Changed MYSQL_INSTANCE to MYSQL_GROUP_SUFFIX
mysql_print_defaults now understands --defaults-group-suffix
Remove usage of my_tempnam() (not safe function)
if( -> if ( and while( to while (
Wrong comparing method were choosen which results in false comparison.
Make Item_bool_func2::fix_length_and_dec() to get type and field from
real_item() to make REF_ITEM pass the check.
Ensure that 'null_value' is not accessed before val() is called in FIELD() functions
Fixed initialization of key maps. This fixes some problems with keys when you have more than 64 keys
Fixed that ROLLUP don't always create a temporary table. This fix ensures that func_gconcat.test results are now predictable
Fixed bug #9939: a wrong conversion of arguments
for functions COALESCE and IFNULL.
The str_op virtual method was added into Item_func_numhybrid.
item_func.cc:
Fixed bug #9939: a wrong conversion of arguments
for functions COALESCE and IFNULL.
The str_op virtual method was added into Item_func_numhybrid.
item_cmpfunc.h, item_cmpfunc.cc:
Fixed bug #9939: a wrong conversion of arguments
for functions COALESCE and IFNULL.
Item_func_coalesce and Item_func_ifnull now
inherit from a modified Item_func_numhybrid.
case.test, case.result:
Added test cases for bug #9939.
This only showed up on two known platforms, both ia64 (one HP-UX and one Linux wich icc).
For some reason, they only get half the stack size they are supposed to have, which
makes deep SP recursion overrun the stack before check_stack_overrun() is triggered.
Also made som minor fixes in the check_stack_overrun() definition, supporting variable
margins.
No test case added, but the reason for the bug report was a failed existing test case
on these machines, which now works.
and bug#8849 "problem with insert statement with table alias's":
make equality propagation work in stored procedures and prepared
statements.
Equality propagation can change AND/OR structure of ON expressions,
so the fix is to provide each execution of PS/SP with it's own
copy of AND/OR tree. We have been doing that already for WHERE clauses,
now ON clauses are also copied.