Optimizer did choose "Range checked for each record" for one of the tables.
For first few loops over that table it choose sequential access, on later
stage it choose to use index. Because table was previously initialized for
sequential access, it skips intitialization for index access, and when
server tries to retrieve data error occurs.
QUICK_RANGE_SELECT::init() changes so if file already initialized for
sequential access, it calls ha_rnd_end() and initializes file for index
access.
The problem was that in the first production in rule 'join_table', that
processes simple cross joins, the parser was processing the second join operand
before the first one due to unspecified priorities of JOINs. As a result in the
case of cross joins the parser constructed a tree with incorrect nesting:
the expression "t1 join t2 join t3 on some_cond" was interpreted as
"t1 join (t2 join t3 on some_cond)" instead of
"(t1 join t2) join t3 on some_cond".
Because of this incorrect nesting the method make_join_on_context picked an
incorrect table as the first table of the name resolution context.
The solution assignes correct priorities to the related production.
(Server crash on DO IFNULL(NULL,NULL)
(fixes also "SELECT CAST(IFNULL(NULL,NULL) as DECIMAL)" unreported
crash)
(new revampled fix with suggestions from Igor)
* Provide backwards compatibility extension to name resolution of
coalesced columns. The patch allows such columns to be qualified
with a table (and db) name, as it is in 4.1.
Based on a patch from Monty.
* Adjusted tests accordingly to test both backwards compatible name
resolution of qualified columns, and ANSI-style resolution of
non-qualified columns.
For this, each affected test has two versions - one with qualified
columns, and one without.
When copying varchar fields with field_conv() it's not taken into account
that length_bytes of source and destination fields may be different.
This results in saving wrong data in field and making wrong key later.
Added check so if fields are varchar and have different length_bytes they
are not copied by memcpy().
"Process NATURAL and USING joins according to SQL:2003".
* Some of the main problems fixed by the patch:
- in "select *" queries the * expanded correctly according to
ANSI for arbitrary natural/using joins
- natural/using joins are correctly transformed into JOIN ... ON
for any number/nesting of the joins.
- column references are correctly resolved against natural joins
of any nesting and combined with arbitrary other joins.
* This patch also contains a fix for name resolution of items
inside the ON condition of JOIN ... ON - in this case items must
be resolved only against the JOIN operands. To support such
'local' name resolution, the patch introduces a stack of
name resolution contexts used at parse time.
NOTICE:
- This patch is not complete in the sense that
- there are 2 test cases that still do not pass -
one in join.test, one in select.test. Both are marked
with a comment "TODO: WL#2486".
- it does not include a new test specific for the task
Added a test case for bug #11745.
sql_select.cc:
Fixed bug # 11745.
Added support of where clause for queries with FROM DUAL.
sql_yacc.yy:
Fixed bug # 11745.
Added optional where clause for queries with FROM DUAL.
"Negative integer keys incorrectly substituted for 0 during range analysis."
The problem is that the range optimizer incorrectly replaces any negative
constant with '0' for all types except BIGINT because the method save_in_field()
casts negative integers to non-negative. This causes incorrect query
results where (0 = any_negative_number).
The problem caused by this bug is fixed by the patch for BUG#11185.
That patch constitutes an optimization due to which the problem code is
never called with negative constants. This patch adds a test so we are sure
that the problem does not reappear.
than in previous 4.1.x
Wrongly applied optimization were adding NOT NULL constraint which results in
rejecting valid rows and reduced result set.
The problem was that add_notnull_conds() while checking subquery were adding
NOT NULL constraint to left joined table, to which, normally, optimization
don't have to be applied.
(IN() remove NULL rows only for tables from first argument (value which we looking for in IN() list) but not for tables from IN() list)
Also it will be better change Item::not_null_tables() to prohibit this optimisation by default for new created items in 5.0 or 5.1.
- Print warning that says display width is not supported for datatype TIMESTAMP, if user tries to create a TIMESTAMP column with display width.
- Use display width for TIMESTAMP only in type_timestamp test to make sure warning is displayed correctly.
The problem: base_list::remove didn't modify base_list::last when removing
the last list element.
The fix: If we remove the last element, find the element before it (by walking
from the beginning of the list) and set base_list::last accordingly.
The list gets corrupted in both 4.0 and 4.1. There are no visible problems in
current 4.1 because current 4.1 doesn't call where_cond->fix_fields() after
constant propagation step.
