ha_myisam::index_first(uchar*)") at assert.c:81
Single-table DELETE crash/assertion similar to single-table
UPDATE bug 14272.
Same resolution as for the bug 14272:
Don't run index scan when we should use quick select.
This could cause failures because there are table handlers (like federated)
that support quick select scanning but do not support index scanning.
in multitable delete/subquery
SQL_BUFFER_RESULT should not have an effect on non-SELECT
statements according to our documentation.
Fixed by not passing it through to multi-table DELETE (similarly
to how it's done for multi-table UPDATE).
DELETE IGNORE
The ER_CANT_UPDATE_USED_TABLE_IN_SF_OR_TRG error was set in the
diagnostics area when it happened, but the DELETE cleanup code
never checked for a non-fatal error condition, thus trying to
set diag.area to "ok". This triggered an assert checking that
the diag.area was empty.
The fix was to test if there existed a non-fatal error condition
(thd->is_error() before ok'ing the operation.
------------------------------------------------------------
revno: 2572.2.1
revision-id: sp1r-davi@mysql.com/endora.local-20080227225948-16317
parent: sp1r-anozdrin/alik@quad.-20080226165712-10409
committer: davi@mysql.com/endora.local
timestamp: Wed 2008-02-27 19:59:48 -0300
message:
Bug#27525 table not found when using multi-table-deletes with aliases over several databas
Bug#30234 Unexpected behavior using DELETE with AS and USING
The multi-delete statement has a documented limitation that
cross-database multiple-table deletes using aliases are not
supported because it fails to find the tables by alias if it
belongs to a different database. The problem is that when
building the list of tables to delete from, if a database
name is not specified (maybe an alias) it defaults to the
name of the current selected database, making impossible to
to properly resolve tables by alias later. Another problem
is a inconsistency of the multiple table delete syntax that
permits ambiguities in a delete statement (aliases that refer
to multiple different tables or vice-versa).
The first step for a solution and proper implementation of
the cross-databse multiple table delete is to get rid of any
ambiguities in a multiple table statement. Currently, the parser
is accepting multiple table delete statements that have no obvious
meaning, such as:
DELETE a1 FROM db1.t1 AS a1, db2.t2 AS a1;
DELETE a1 AS a1 FROM db1.t1 AS a1, db2.t2 AS a1;
The solution is to resolve the left part of a delete statement
using the right part, if the a table on right has an alias,
it must be referenced in the left using the given alias. Also,
each table on the left side must match unambiguously only one
table in the right side.
trigger, merge table
The problem with break statements is that they have very
local effects. Hence a break statement within the inner loop
of a nested-loops join caused execution to proceed to the
next table even though a serious error occurred. The problem
was fixed by breaking out the inner loop into its own
method. The change empowers all errors to terminate the
execution.
The errors that will now halt multi-DELETE execution
altogether are
- triggers returning errors
- handler errors
- server being killed
Anti-patch. This patch undoes the previously pushed patch. It is
null-merged in versions 5.1 and above since there the original
patch is still desired.
an error, asserts server
In case of a fatal error during filesort in find_all_keys() the error
was returned without the necessary handler uninitialization.
Fixed by changing the code so that handler uninitialization is performed
before returning the error.
DELETE FROM ... USING ... statements with the following type of
ambiguous aliasing gave unexpected results:
DELETE FROM t1 AS alias USING t1, t2 AS alias WHERE t1.a = alias.a;
This query would leave table t1 intact but delete rows from t2.
Fixed by changing DELETE FROM ... USING syntax so that only alias
references (as opposed to alias declarations) may be used in FROM.
When handling DELETE ... FROM if there is no
condition it is internally transformed to
TRUNCATE for more efficient execution by the
storage handler.
The check for validity of the optional ORDER BY
clause is done after the check for the above
optimization and will not be performed if the
optimization can be applied.
Moved the validity check for ORDER BY before
the optimization so it performed regardless of
the optimization.
WHERE is present.
If a DELETE statement with ORDER BY and LIMIT contains a WHERE clause
with conditions that for sure cannot be used for index access (like in
WHERE @var:= field) the execution always follows the filesort path.
It happens currently even when for the above case there is an index that
can be used to speedup sorting by the order by list.
Now if a DELETE statement with ORDER BY and LIMIT contains such WHERE
clause conditions that cannot be used to build any quick select then
the mysql_delete() tries to use an index like there is no WHERE clause at all.
1003: Incorrect table name
in multi-table DELETE the set of tables to delete from actually
references then tables in the other list, e.g:
DELETE alias_of_t1 FROM t1 alias_of_t1 WHERE ....
is a valid statement.
So we must turn off table name syntactical validity check for alias_of_t1
because it's not a table name (even if it looks like one).
In order to do that we add a special flag (TL_OPTION_ALIAS) to
disable the name checking for the aliases in multi-table DELETE.
Added a test case for bug #8392.
sql_delete.cc:
Fixed bug #8392.
The bug caused a crash for a delete statement with ORDER BY
that explicitly referred to the modified table.
Added more DBUG statements
Ensure that we are comparing end space with BINARY strings
Use 'any_db' instead of '' to mean any database. (For HANDLER command)
Only strip ' ' when comparing CHAR, not other space-like characters (like \t)