In practice this means that handlerton is now created by the server and is passed to the engine. Plugin startups can now also control how plugins are inited (and can optionally pass values). Bit more flexibility to those who want to write plugin interfaces to the database.
from cache" and #21216 "Simultaneous DROP TABLE and SHOW OPEN TABLES causes
server to crash".
Crash happened when one ran DROP DATABASE or SHOW OPEN TABLES statements
while concurrently doing DROP TABLE (or RENAME TABLE, CREATE TABLE LIKE
or any other command that takes name-lock) in other connection.
This problem was caused by the fact that table placeholders which were
added to table cache in order to obtain name-lock on table had
TABLE_SHARE::db and table_name set to 0. Therefore they broke assumption
that these members are non-0 for all tables in table cache on which some
of our code relies.
The fix sets these members for such placeholders to appropriate value making
this assumption true again. As attempt to avoid such problems in future
we introduce auxiliary TABLE_SHARE::set_table_cache_key() methods which
should be used when one wants to set TABLE_SHARE::table_cache_key and which
ensure that TABLE_SHARE::table_name/db are set properly.
Test cases for these bugs were added to 5.0 test-suite (with 5.0-specific
fix for bug #21216).
Continued implementation of WL#1324 (table name to filename encoding)
The intermediate (not temporary) files of the new table
during ALTER TABLE was visible for SHOW TABLES. These
intermediate files are copies of the original table with
the changes done by ALTER TABLE. After all the data is
copied over from the original table, these files are renamed
to the original tables file names. So they are not temporary
files. They persist after ALTER TABLE, but just with another
name.
In 5.0 the intermediate files are invisible for SHOW TABLES
because all file names beginning with "#sql" were suppressed.
This failed since 5.1.6 because even temporary table names were
converted when making file names from them. The prefix became
converted to "@0023sql". Converting the prefix during SHOW TABLES
would suppress the listing of user tables that start with "#sql".
The solution of the problem is to continue the implementation of
the table name to file name conversion feature. One requirement
is to suppress the conversion for temporary table names.
This change is straightforward for real temporary tables as there
is a function that creates temporary file names.
But the generated path names are located in TMPDIR and have no
relation to the internal table name. This cannot be used for
ALTER TABLE. Its intermediate files need to be in the same
directory as the old table files. And it is necessary to be
able to deduce the same path from the same table name repeatedly.
Consequently the intermediate table files must be handled like normal
tables. Their internal names shall start with tmp_file_prefix
(#sql) and they shall not be converted like normal table names.
I added a flags parameter to all relevant functions that are
called from ALTER TABLE. It is used to suppress the conversion
for the intermediate table files.
The outcome is that the suppression of #sql in SHOW TABLES
works again. It does not suppress user tables as these are
converted to @0023sql on file level.
This patch does also fix ALTER TABLE ... RENAME, which could not
rename a table with non-ASCII characters in its name.
It does also fix the problem that a user could create a table like
`#sql-xxxx-yyyy`, where xxxx is mysqld's pid and yyyy is the thread
ID of some other thread, which prevented this thread from running
ALTER TABLE.
Some of the above problems are mentioned in Bug 1405, which can
be closed with this patch.
This patch does also contain some minor fixes for other forgotten
conversions. Still known problems are reported as bugs 21370,
21373, and 21387.
dropping/creating tables".
The bug could lead to a crash when multi-delete statements were
prepared and used with temporary tables.
The bug was caused by lack of clean-up of multi-delete tables before
re-execution of a prepared statement. In a statement like
DELETE t1 FROM t1, t2 WHERE ... the first table list (t1) is
moved to lex->auxilliary_table_list and excluded from lex->query_tables
or select_lex->tables. Thus it was unaccessible to reinit_stmt_before_use
and not cleaned up before re-execution of a prepared statement.
before update trigger on NDB table".
Two main changes:
- We use TABLE::read_set/write_set bitmaps for marking fields used by
statement instead of Field::query_id in 5.1.
- Now when we mark columns used by statement we take into account columns
used by table's triggers instead of marking all columns as used if table
has triggers.
Table comment: issue a warning(error in traditional mode) if length of comment > 60 symbols
Column comment: issue a warning(error in traditional mode) if length of comment > 255 symbols
Table 'comment' is changed from char* to LEX_STRING
Bug#17294 - INSERT DELAYED puting an \n before data
Bug#16611 - INSERT DELAYED corrupts data
Bug#13707 - Server crash with INSERT DELAYED on MyISAM table
Combined as Bug#16218.
INSERT DELAYED crashed in 5.0 on a table with a varchar that
could be NULL and was created pre-5.0 (Bugs 16218 and 13707).
INSERT DELAYED corrupted data in 5.0 on a table with varchar
fields that was created pre-5.0 (Bugs 17294 and 16611).
In case of INSERT DELAYED the open table is copied from the
delayed insert thread to be able to create a record for the
queue. When copying the fields, a method was used that did
convert old varchar to new varchar fields and did not set up
some pointers into the record buffer of the table.
The field conversion was guilty for the misinterpretation of
the record contents by the delayed insert thread. The wrong
pointer setup was guilty for the crashes.
For Bug 13707 (Server crash with INSERT DELAYED on MyISAM table)
I fixed the above mentioned method to set up one of the pointers.
For Bug 16218 I set up the other pointers too.
But when looking at the corruptions I got aware that converting
the field type was totally wrong for INSERT DELAYED. The copied
table is used to create a record that is to be sent to the
delayed insert thread. Of course it can interpret the record
correctly only if all field types are the same in both table
objects.
So I revoked the fix for Bug 13707 and changed the new_field()
method so that it can suppress conversions.
No test case as this is a migration problem. One needs to
create a table with 4.x and use it with 5.x. I added two
test scripts to the bug report.
