of its argument happened to be a decimal expression returning
the NULL value.
The crash was due to the fact the function in_decimal::set did
not take into account that val_decimal() could return 0 if
the decimal expression had been evaluated to NULL.
INTO clause can be specified only for the last select of a UNION and it
receives the result of the whole query. But it was wrongly allowed in
non-last selects of a UNION which leads to a confusing query result.
Now INTO allowed only in the last select of a UNION.
aggregated in outer context returned wrong results.
This happened only if the subquery did not contain any references
to outer fields.
As there were no references to outer fields the subquery erroneously
was taken for non-correlated one.
Now any set function aggregated in outer context makes the subquery
correlated.
To correctly decide which predicates can be evaluated with a given table
the optimizer must know the exact set of tables that a predicate depends
on. If that mask is too wide (refer to non-existing tables) the optimizer
can erroneously skip a predicate.
One such case of wrong table usage mask were the aggregate functions.
The have a all-1 mask (meaning depend on all tables, including non-existent
ones).
Fixed by making a real used_tables mask for the aggregates. The mask is
constructed in the following way :
1. OR the table dependency masks of all the arguments of the aggregate.
2. If all the arguments of the function are from the local name resolution
context and it is evaluated in the same name resolution
context where it is referenced all the tables from that name resolution
context are OR-ed to the dependency mask. This is to denote that an
aggregate function depends on the number of rows it processes.
3. Handle correctly the case of an aggregate function optimization (such that
the aggregate function can be pre-calculated and made a constant).
Made sure that an aggregate function is never a constant (unless subject of a
specific optimization and pre-calculation).
One other flaw was revealed and fixed in the process : references were
not calling the recalculation method for used_tables of their targets.
Removed wrong fix for the bug#27006.
The bug was added by the fix for the bug#19978 and fixed by Monty on 2007/02/21.
trigger.test, trigger.result:
Corrected test case for the bug#27006.
BUG#26429: SHOW CREATE EVENT is incorrect for an event that
STARTS NOW()
BUG#26431: Impossible to re-create an event from backup if its
STARTS clause is in the past
WL#3698: Events: execution in local time zone
The problem was that local times specified by the user in AT, STARTS
and ENDS of CREATE EVENT/ALTER EVENT statement were converted to UTC,
and the original time zone was forgotten. This way, event scheduler
couldn't honor Daylight Saving Time shifts, and times shown to the
user were also in UTC. Additionally, CREATE EVENT didn't allow times
in the past, thus preventing straightforward event restoration from
old backups.
This patch reworks event scheduler time computations, performing them
in the time zone associated with the event. Also it allows times to
be in the past.
The patch adds time_zone column to mysql.event table.
NOTE: The patch is almost final, but the bug#9953 should be pushed
first.
UPDATE if the row wasn't actually changed.
This bug was caused by fix for bug#19978. It causes AFTER UPDATE triggers
not firing if a row wasn't actually changed by the update part of the
INSERT .. ON DUPLICATE KEY UPDATE.
Now triggers are always fired if a row is touched by the INSERT ... ON
DUPLICATE KEY UPDATE.
- Crash occured because Event engine is only initialized if
ACLs are used but not properly marked as disabled.
- The patch is to mark the Event engine as DISABLED if no ACLs
are used to avoid access of uninitialized variables.
INSERT uses query_id to verify what fields are
mentioned in the fields list of the INSERT command.
However the check for that is made after the
ON DUPLICATE KEY is processed. This causes all
the fields mentioned in ON DUPLICATE KEY to be
considered as mentioned in the fields list of
INSERT.
Moved the check up, right after processing the
fields list.
touched but not actually changed.
The LAST_INSERT_ID() is reset to 0 if no rows were inserted or changed.
This is the case when an INSERT ... ON DUPLICATE KEY UPDATE updates a row
with the same values as the row contains.
Now the LAST_INSERT_ID() values is reset to 0 only if there were no rows
successfully inserted or touched.
The new 'touched' field is added to the COPY_INFO structure. It holds the
number of rows that were touched no matter whether they were actually
changed or not.
Before this fix, the parser would accept illegal code in SQL exceptions
handlers, that later causes the runtime to crash when executing the code,
due to memory violations in the exception handler stack.
The root cause of the problem is instructions within an exception handler
that jumps to code located outside of the handler. This is illegal according
to the SQL 2003 standard, since labels located outside the handler are not
supposed to be visible (they are "out of scope"), so any instruction that
jumps to these labels, like ITERATE or LEAVE, should not parse.
The section of the standard that is relevant for this is :
SQL:2003 SQL/PSM (ISO/IEC 9075-4:2003)
section 13.1 <compound statement>,
syntax rule 4
<quote>
The scope of the <beginning label> is CS excluding every <SQL schema
statement> contained in CS and excluding every
<local handler declaration list> contained in CS. <beginning label> shall
not be equivalent to any other <beginning label>s within that scope.
</quote>
With this fix, the C++ class sp_pcontext, which represent the "parsing
context" tree (a.k.a symbol table) of a stored procedure, has been changed
as follows:
- constructors have been cleaned up, so that only building a root node for
the tree is public; building nodes inside a tree is not public.
- a new member, m_label_scope, indicates if a given syntactic context
belongs to a DECLARE HANDLER block,
- label resolution, in the method find_label(), has been changed to
implement the restriction of scope regarding labels used in a compound
statement.
The actions in the parser, when parsing the body of a SQL exception handler,
have been changed as follows:
- the implementation of an exception handler (DECLARE HANDLER) now creates
explicitly a new sp_pcontext, to isolate the code inside the handler from
the containing compound statement context.
- registering exception handlers as a result occurs in the parent context,
see the rule sp_hcond_element
- the code in sp_hcond_list has been cleaned up, to avoid code duplication
In addition, the flags IN_SIMPLE_CASE and IN_HANDLER, declared in sp_head.h
have been removed, since they are unused and broken by design (as seen with
Bug 19194 (Right recursion in parser for CASE causes excessive stack usage,
limitation), representing a stack in a single flag is not possible.
Tests in sp-error have been added to show that illegal constructs are now
rejected.
Tests in sp have been added for code coverage, to show that ITERATE or LEAVE
statements are legal when jumping to a label in scope, inside the body of
an exception handler.
This bug was intruduced by the fix for bug#17212 (in 4.1). It is not
ok to call test_if_skip_sort_order since this function will
alter the execution plan. By contract it is not ok to call
test_if_skip_sort_order in this context.
This bug appears only in the case when the optimizer has chosen
an index for accessing a particular table but finds a covering
index that enables it to skip ORDER BY. This happens in
test_if_skip_sort_order.
It was syntactically correct to define
spatial keys over parts of columns (e.g.
ALTER TABLE t1 ADD x GEOMETRY NOT NULL,
ADD SPATIAL KEY (x(32))).
This may lead to undefined results and/or
interpretation.
Fixed by not allowing partial column
specification in a SPATIAL index definition.
Different set of conditions is used to verify
the validity of index definitions over a GEOMETRY
column in ALTER TABLE and CREATE TABLE.
The difference was on how sub-keys notion validity
is checked.
Fixed by extending the CREATE TABLE condition to
support the cases allowed in ALTER TABLE.
Made the SHOW CREATE TABLE not to display spatial
indexes using the sub-key notion.
