Item::val_xxx() may be called by the server several times at execute time
for a single query. Calls to val_xxx() may be very expensive and sometimes
(count(distinct), sum(distinct), avg(distinct)) not possible.
To avoid that problem the results of calculation for these aggregate
functions are cached so that val_xxx() methods just return the calculated
value for the second and subsequent calls.
If the user has specified --max-connections=N or --table-open-cache=M
options to the server, a warning could be given that some values were
recalculated, and table-open-cache could be assigned greater value.
Note that both warning and increase of table-open-cache were totally
harmless.
This patch fixes recalculation code to ensure that table-open-cache will
be never increased automatically and that a warning will be given only if
some values had to be decreased due to operating system limits.
No test case is provided because we neither can't predict nor control
operating system limits for maximal number of open files.
It's not possible to flush the global status variables in 5.0
Update test case so it works by recording the value of handle_rollback
before and compare it to the value after
Problem: SHOW CREATE TABLE printed garbage in table
name for tables having TURKISH I
(i.e. LATIN CAPITABLE LETTER I WITH DOT ABOVE)
when lower-case-table-name=1.
Reason: In some cases during lower/upper conversion in utf8,
the result string can be shorter the original string
(including the above letter). Old implementation of caseup_str()
and casedn_str() didn't handle the result length properly,
assuming that length cannot change.
This fix changes the result type of cs->cset->casedn_str()
and cs->cset->caseup_str() from VOID to UINT, to return
the result length, as well as put '\0' terminator on a
proper place.
Also, my_caseup_str_utf8() and my_casedn_str_utf8() were
rewritten not to use strlen() for performance purposes.
It was done with help of adding of new functions - my_utf8_uni_no_range()
and my_uni_utf8_no_range() - for null terminated strings.
Problem: Too confusing error message when cannot convert
between string and column character sets on INSERT and UPDATE.
Fix: producing a better error message, instead of "Data too long"
in such cases
Additional changes: Adding "DROP TABLE IF EXISTS" into several
tests to be safe against failures in previous tests.
decimal->ulong conversion fixed to assign max possible ULONG if decimal
is bigger
Item_func_unsigned now handles DECIMAL parameter separately as we can't
rely on decimal::val_int result here.
a updatable view.
When there's a VIEW on a base table that have AUTO_INCREMENT column, and
this VIEW doesn't provide an access such column, after INSERT to such
VIEW LAST_INSERT_ID() did not return the value just generated.
This behaviour is intended and correct, because if the VIEW doesn't list
some columns then these columns are effectively hidden from the user,
and so any side effects of inserting default values to them.
However, there was a bug that such statement inserting into a view would
reset LAST_INSERT_ID() instead of leaving it unchanged.
This patch restores the original value of LAST_INSERT_ID() instead of
resetting it to zero.
- As a sideeffect of the patch to generate lex_hash.h only once
on the machine where the source dist was produced, a problem
was found when compiling a mysqld without partition support - it
would crash when looking up the lex symbols due to mismatch between
lex.h and the generated lex_hash.h
- Remove the ifdef for partition in lex.h
- Fix minor problem with"EXPLAIN PARTITION" when not compiled with
partition(existed also without the above patch)
- Add test case that will be run when we don't have partition
support compiled into mysqld
- Return error ER_FEATURE_DISABLED if user tries to use PARTITION
when there is no support for it.
When executing the init_connect statement, thd->net.vio is set to 0, to
forbid sending any results to the client. As a side effect we don't log
possible errors, either.
Now we write warnings to the error log if an init_connect query
fails.
If the error happens during DELETE IGNORE, nothing could be send to the
client, thus leaving it frozen expecting the reply.
The problem was that if some error occurred, it wouldn't be reported to
the client because of IGNORE, but neither success would be reported.
MySQL 4.1 would not freeze the client, but will report
ERROR 1105 (HY000): Unknown error
instead, which is also a bug.
The solution is to report success if we are in DELETE IGNORE and some
non-fatal error has happened.
select OK.
The SQL parser was using Item::name to transfer user defined function attributes
to the user defined function (udf). It was not distinguishing between user defined
function call arguments and stored procedure call arguments. Setting Item::name
was causing Item_ref::print() method to print the argument as quoted identifiers
and caused views that reference aggregate functions as udf call arguments (and
rely on Item::print() for the text of the view to store) to throw an undefined
identifier error.
Overloaded Item_ref::print to print aggregate functions as such when printing
the references to aggregate functions taken out of context by split_sum_func2()
Fixed the parser to properly detect using AS clause in stored procedure arguments
as an error.
Fixed printing the arguments of udf call to print properly the udf attribute.
Problem: "greater than" and "less than" XPath operators appeared to have been implemented in reverse.
Fix: swap arguments to eq_func() and eq_func_reverse() to provide correct operation result.
when doing create unique index which mysql will silently converts to PK, ndb is not informed
so table will be useless.
change so that we never do online add index wo/ primary key.
this is not good, but it's better than a useless table
warnings in sql_trigger.cc and sql_view.cc".
According to the current version of C++ standard offsetof() macro
can't be used for non-POD types. So warnings were emitted when we
tried to use this macro for TABLE_LIST and Table_triggers_list
classes. Note that despite of these warnings it was probably safe
thing to do.
This fix tries to circumvent this limitation by implementing
custom version of offsetof() macro to be used with these
classes. This hack should go away once we will refactor
File_parser class.
Alternative approaches such as disabling this warning for
sql_trigger.cc/sql_view.cc or for the whole server were
considered less explicit. Also I was unable to find a way
to disable particular warning for particular _part_ of
file in GCC.
- compilation on the Alpha platform was broken because the Alpha-specific code was not updated after replacing the SIGRETURN_FRAME_COUNT constant with a variable
If elements a not top-level IN subquery were accessed by an index and
the subquery result set included a NULL value then the quantified
predicate that contained the subquery was evaluated to NULL when
it should return a non-null value.
This patch reverts a change introduced by Bug 6951, which incorrectly
set thd->abort_on_warning for stored procedures.
As per internal discussions about the SQL_MODE=TRADITIONAL,
the correct behavior is to *not* abort on warnings even inside an INSERT/UPDATE
trigger.
Tests for Stored Procedures, Stored Functions, Triggers involving SQL_MODE
have been included or revised, to reflect the intended behavior.
(reposting approved patch, to work around source control issues, no review needed)
with only COMMENT clause. Strangely it has manifestated itself
only on two platforms. This is a fix for bug#23423
"Syntax error for "ALTER EVENT ... COMMENT ..." on just two platforms"
Backport from 5.1.
Raised STACK_MIN_SIZE for Debian GNU/Linux Sid,
Linux kernel 2.6.16,
gcc version 3.3.6 (Debian 1:3.3.6-13),
libc6-dbg 2.3.6.ds1-4,
Pentium4 (x86),
BUILD/compile-pentium-debug-max
Raised about 100 Bytes above the required minimum.
When statement to be prepared contained CREATE PROCEDURE, CREATE FUNCTION
or CREATE TRIGGER statements with a syntax error in it, the preparation
would fail with syntax error message, but the memory could be corrupted.
The problem occurred because we switch memroot when parse stored
routine or trigger definitions, and on parse error we restored the
original memroot only after performing some memory operations. In more
detail:
- prepared statement would activate its own memory root to parse
the definition of the stored procedure.
- SP would reset this memory root with its own memory root to
parse SP statements
- a syntax error would happen
- prepared statement would restore the original memory root
- stored procedure would restore what it thinks was the original
memory root, but actually was the statement memory root.
That led to double free - in destruction of the statement and in
a next call to mysql_parse().
The solution is to restore memroot right after the failed parsing.
The value taken to be shown in SHOW PROCESSLIST is not
initialized when THD is created and will be random for
unauthenticated connections.
To the documentor: Random value, instead of NULL, was shown,
in SHOW PROCESSLIST for still non-authenticated connections.
We miss some records sometimes using RANGE method if we have
partial key segments.
Example:
Create table t1(a char(2), key(a(1)));
insert into t1 values ('a'), ('xx');
select a from t1 where a > 'x';
We call index_read() passing 'x' key and HA_READ_AFTER_KEY flag
in the handler::read_range_first() wich is wrong because we have
a partial key segment for the field and might miss records like 'xx'.
Fix: don't use open segments in such a case.
The value taken to be shown in SHOW PROCESSLIST is not
initialized when THD is created and will be random for
unauthenticated connections.
To the documentor: Random value, instead of NULL, was shown,
in SHOW PROCESSLIST for still non-authenticated connections.
(COUNT(*) = 1) not working in SELECT inside prepared statement.
Note: the warning was introduced in 5.0 and 5.1, 4.1 is OK with the
original fix.
The problem was that in 5.0 and 5.1 clear() for group functions may
access hybrid_type member, and this member is initialized in
fix_fields().
So we should not call clear() from item cleanup() methods, as cleanup()
may be called for unfixed items.
list using a function
When executing dependent subqueries they are re-inited and re-exec() for
each row of the outer context.
The cause for the bug is that during subquery reinitialization/re-execution,
the optimizer reallocates JOIN::join_tab, JOIN::table in make_simple_join()
and the local variable in 'sortorder' in create_sort_index(), which is
allocated by make_unireg_sortorder().
Care must be taken not to allocate anything into the thread's memory pool
while re-initializing query plan structures between subquery re-executions.
All such items mush be cached and reused because the thread's memory pool
is freed at the end of the whole query.
Note that they must be cached and reused even for queries that are not
otherwise cacheable because otherwise it will grow the thread's memory
pool every time a cacheable query is re-executed.
We provide additional members to the JOIN structure to store references
to the items that need to be cached.
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.
Problem: renaming of FRM file and ARC files didn't use file name
encoding, so RENAME TABLE for views failed for views having
"tricky" characters in their names.
Fix: adding build_table_filename() in missing places.
When using index for group by and range access the server isolates
a set of ranges based on the conditions over the key parts of the
index used. Then it uses only the ranges over the GROUP BY fields to
jump from one group to another. Since the GROUP BY fields may form a
prefix over the index, we may use only a prefix of the ranges produced
by the range optimizer.
Each range contains a notion on whether it includes its border values.
The problem is that when using a range prefix, the last range is open
because it assumes that there is a range on the next keypart. Thus when
we use a prefix range as it is, it excludes all border values.
The solution is when ignoring the suffix of the range conditions
(to jump over the GROUP BY prefix only) the server must change the
remaining intervals so they always contain their borders, e.g.
if the whole range was :
(1,-inf) <= (<group_by_col>,<min_max_arg_col>) < (1, 3) we must make
(1) <= (<group_by_col>) <= (1) because (a,b) < (c1,c2) means :
a < c1 OR (a = c1 AND b < c2).
When resolving unqualified name references MySQL was not
checking what is the item type for the reference. Thus
e.g a string literal item that has by convention a name
equal to its string value will also work as a reference to
a SELECT list item or a table field.
Fixed by allowing only Item_ref or Item_field to referenced by
(unqualified) name.
The mysql_alter_table() was able to rename only a table.
The view/table renaming code is moved from the function rename_tables
to the new function called do_rename().
The mysql_alter_table() function calls it when it needs to rename a view.
