The function make_unireg_sortorder ignored the fact that any
view field is represented by a 'ref' object.
This could lead to wrong results for the queries containing
both GROUP BY and ORDER BY clauses.
present.
A view created with CREATE VIEW ... ORDER BY ... cannot be resolved with
the MERGE algorithm, even when no other part of the CREATE VIEW statement
would require the view to be resolved using the TEMPTABLE algorithm.
The check for presence of the ORDER BY clause in the underlying select is
removed from the st_lex::can_be_merged() function.
The ORDER BY list of the underlying select is appended to the ORDER BY list
View check option clauses were ignored for updates of multi-table
views when the updates could not be performed on fly and the rows
to update had to be put into temporary tables first.
with a column of the DATETIME type could return a wrong
result set if the WHERE clause included a BETWEEN condition
on the column.
Fixed the method Item_func_between::fix_length_and_dec
where the aggregation type for BETWEEN predicates calculated
incorrectly if the first argument was a view column of the
DATETIME type.
when they contain the '!' operator.
Added an implementation for the method Item_func_not::print.
The method encloses any NOT expression into extra parentheses to avoid
incorrect stored representations of views that use the '!' operators.
Without this change when a view was created that contained
the expression !0*5 its stored representation contained not this
expression but rather the expression not(0)*5 .
The operator '!' is of a higher precedence than '*', while NOT is
of a lower precedence than '*'. That's why the expression !0*5
is interpreted as not(0)*5, while the expression not(0)*5 is interpreted
as not((0)*5) unless sql_mode is set to HIGH_NOT_PRECEDENCE.
Now we translate !0*5 into (not(0))*5.
If SELECT-part of CREATE VIEW statement contains '\Z',
it is not handled correctly.
The problem was in String::print().
Symbol with code 032 (26) is replaced with '\z',
which is not supported by the lexer.
The fix is to replace the symbol with '\Z'.
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.
should fail to create
The problem was that this type of errors was checked during view
creation, which doesn't happen when CREATE VIEW is a statement of
a created stored routine.
The solution is to perform the checks at parse time. The idea of the
fix is that the parser checks if a construction just parsed is allowed
in current circumstances by testing certain flags, and this flags are
reset for VIEWs.
The side effect of this change is that if the user already have
such bogus routines, it will now get a error when trying to do
SHOW CREATE PROCEDURE proc;
(and some other) and when trying to execute such routine he will get
ERROR 1457 (HY000): Failed to load routine test.p5. The table mysql.proc is missing, corrupt, or contains bad data (internal code -6)
However there should be very few such users (if any), and they may
(and should) drop these bogus routines.
In a trigger or a function used in a statement it is possible to do
SELECT from a table being modified by the statement. However,
encapsulation of such SELECT into a view and selecting from a view
instead of direct SELECT was not possible.
This happened because tables used by views (which in their turn
were used from functions/triggers) were not excluded from checks
in unique_table() routine as it happens for the rest of tables
added to the statement table list for prelocking.
With this fix we ignore all such tables in unique_table(), thus
providing consistency: inside a trigger or a functions SELECT from
a view may be used where plain SELECT is allowed. Modification of
the same table from function or trigger is still disallowed. Also,
this patch doesn't affect the case where SELECT from the table being
modified is done outside of function of trigger, such SELECTs are
still disallowed (this limitation and visibility problem when function
select from a table being modified are subjects of bug 21326). See
also bug 22427.
We use the condition from CHECK OPTION twice handling UPDATE command.
First we construnct 'update_cond' AND 'option_cond'
condition to select records to be updated, then we check the
'option_cond' for the updated row.
The problem is that first 'AND' condition is optimized during the 'select'
which can break 'option_cond' structure, so it will be unusable for
the sectond use - to check the updated row.
Possible soultion is either use copy of the condition in the first
use or to make optimization less traumatic for the operands.
I picked the first one.
On an INSERT into an updatable but non-insertable view an error message was
issued stating the view being not updatable. This can lead to a confusion of a
user.
A new error message is introduced. Is is showed when a user tries to insert
into a non-insertable view.
Presence of a subquery in the ON expression of a join
should not block merging the view that contains this join.
Before this patch the such views were converted into
into temporary table views.
Select_type in the EXPLAIN output for the query SELECT * FROM t1 was
'SIMPLE', while for the query SELECT * FROM v1, where the view v1
was defined as SELECT * FROM t1, the EXPLAIN output contained 'PRIMARY'
for the select_type column.
When a view was used inside a trigger or a function, lock type for
tables used in a view was always set to READ (thus making the view
non-updatable), even if we were trying to update the view.
The solution is to set lock type properly.
User name (host name) has limit on length. The server code relies on these
limits when storing the names. The problem was that sometimes these limits
were not checked properly, so that could lead to buffer overflow.
The fix is to check length of user/host name in parser and if string is too
long, throw an error.
SELECT right instead of INSERT right was required for an insert into to a view.
This wrong behaviour appeared after the fix for bug #20989. Its intention was
to ask only SELECT right for all tables except the very first for a complex
INSERT query. But that patch has done it in a wrong way and lead to asking
a wrong access right for an insert into a view.
The setup_tables_and_check_access() function now accepts two want_access
parameters. One will be used for the first table and the second for other
tables.
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.
When executing ALTER TABLE all the attributes of the view were overwritten.
This is contrary to the user's expectations.
So some of the view attributes are preserved now : namely security and
algorithm. This means that if they are not specified in ALTER VIEW
their values are preserved from CREATE VIEW instead of being defaulted.
When executing INSERT over a view with calculated columns it was assuming all
elements of the fields collection are actually Item_field instances.
This may not be true when inserting into a view and that view has columns that are
such expressions that allow updating (like setting a collation for example).
Corrected to access field information through the filed_for_view_update() function and
retrieve correctly the field info even for "update-friendly" non-Item_field items.
DESCRIBE returned the type BIGINT for a column of a view if the column
was specified by an expression over values of the type INT.
E.g. for the view defined as follows:
CREATE VIEW v1 SELECT COALESCE(f1,f2) FROM t1
DESCRIBE returned type BIGINT for the only column of the view if f1,f2 are
columns of the INT type.
At the same time DESCRIBE returned type INT for the only column of the table
defined by the statement:
CREATE TABLE t2 SELECT COALESCE(f1,f2) FROM t1.
This inconsistency was removed by the patch.
Now the code chooses between INT/BIGINT depending on the
precision of the aggregated column type.
Thus both DESCRIBE commands above returns type INT for v1 and t2.
When compiling INSERT statements the check whether columns are provided values
depends on the flag whether a field is used in that query (Field::query_id).
However the check for updatability of VIEW columns (check_view_insertability())
was calling fix_fields() and thus setting the Field::query_id even for the
view fields that are not referenced in the current INSERT statement.
So the correct check for columns without default values
( check_that_all_fields_are_given_values() ) is assuming that all the VIEW
columns were mentioned in the INSERT field list and was issuing no
warnings or errors.
Fixed check_view_insertability() to turn off the flag whether or not to set
Field::query_id (THREAD::set_query_id) before calling fix fields and restore
it when it's done.
When a CREATE TABLE command created a table from a materialized
view id does not inherit default values from the underlying table.
Moreover the temporary table used for the view materialization
does not inherit those default values.
In the case when the underlying table contained ENUM fields it caused
misleading error messages. In other cases the created table contained
wrong default values.
The code was modified to ensure inheritance of default values for
materialized views.
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.