fix the following type mrr scan
(select 0,`id`,`node` from `auto_test_remote`.`tbl_a` where (`id` <> 0) order by `id`)union all(select 1,`id`,`node` from `auto_test_remote`.`tbl_a` where (`id` <> 0) order by `id`) order by `id`
fix the following type mrr scan
(select 0,`id`,`node` from `auto_test_remote`.`tbl_a` where (`id` <> 0) order by `id`)union all(select 1,`id`,`node` from `auto_test_remote`.`tbl_a` where (`id` <> 0) order by `id`) order by `id`
fix the following type mrr scan
(select 0,`id`,`node` from `auto_test_remote`.`tbl_a` where (`id` <> 0) order by `id`)union all(select 1,`id`,`node` from `auto_test_remote`.`tbl_a` where (`id` <> 0) order by `id`) order by `id`
Final added to:
- All reasonable classes inhereted from Field
- All classes inhereted from Protocol
- Almost all Handler classes
- Some important Item classes
The stripped size of mariadbd is just 4K smaller, but several object files
showed notable improvements in common execution paths.
- Checked field.o and item_sum.o
Other things:
- Added 'override' to a few class functions touched by this patch.
- Removed 'virtual' from a new class functions that had/got 'override'
- Changed Protocol_discard to inherit from Protocol instad of Protocol_text
- Include a link to the relevant KB article for more info
- Use spaced around the equal sign for better readability and so that
the examples are more aligned with the general style in the KB
- Load plugins with just the base name, the .so is optional and excess
- Better to use 'String *' directly.
- Added String::get_value(LEX_STRING*) for the few cases where we want to
convert a String to LEX_CSTRING.
Other things:
- Use StringBuffer for some functions to avoid mallocs
The COM_MULTI did not take off. No connector is using it.
Remove related code from server, and client.
If anything it is a step simplification of already-bloated
dispatch_command(), and related code.
Fix the following valgrind error.
==94390== Thread 29:
==94390== Invalid read of size 8
==94390== at 0x78389D: thd_increment_bytes_sent (sql_class.cc:4265)
==94390== by 0xC8EC46: net_real_write (net_serv.cc:730)
==94390== by 0xC8E0C8: net_flush (net_serv.cc:383)
==94390== by 0xC8E4D0: net_write_command (net_serv.cc:521)
==94390== by 0xADCE61: cli_advanced_command (client.c:468)
==94390== by 0xAE3CAF: mysql_close_slow_part (client.c:3671)
==94390== by 0xAE3D28: mysql_close (client.c:3683)
==94390== by 0x149E69A8: spider_db_mbase::disconnect() (spd_db_mysql.cc:2217)
==94390== by 0x1491EA26: spider_db_disconnect(st_spider_conn*) (spd_db_conn.cc:297)
==94390== by 0x14948EBE: spider_free_conn_alloc(st_spider_conn*) (spd_conn.cc:196)
==94390== by 0x1494B26A: spider_free_conn(st_spider_conn*) (spd_conn.cc:1251)
==94390== by 0x1494941F: spider_free_conn_from_trx(st_spider_transaction*, st_spider_conn*, bool, bool, int*) (spd_conn.cc:315)
==94390== Address 0x1f0e0990 is 4,832 bytes inside a block of size 25,728 free'd
==94390== at 0x4C2ACBD: free (vg_replace_malloc.c:530)
==94390== by 0x13F5545: my_free (my_malloc.c:222)
==94390== by 0x6C75B7: ilink::operator delete(void*, unsigned long) (sql_list.h:618)
==94390== by 0x77B9F6: THD::~THD() (sql_class.cc:1724)
==94390== by 0x1494FCE0: spider_bg_conn_action(void*) (spd_conn.cc:2580)
==94390== by 0x4E3DDD4: start_thread (in /usr/lib64/libpthread-2.17.so)
==94390== by 0x5FBFEAC: clone (in /usr/lib64/libc-2.17.so)
==94390== Block was alloc'd at
==94390== at 0x4C29BC3: malloc (vg_replace_malloc.c:299)
==94390== by 0x13F4DFA: my_malloc (my_malloc.c:101)
==94390== by 0x1491CF06: ilink::operator new(unsigned long) (sql_list.h:614)
==94390== by 0x1494F7FD: spider_bg_conn_action(void*) (spd_conn.cc:2501)
==94390== by 0x4E3DDD4: start_thread (in /usr/lib64/libpthread-2.17.so)
==94390== by 0x5FBFEAC: clone (in /usr/lib64/libc-2.17.so)
==94390== Invalid write of size 8
==94390== at 0x7838AF: thd_increment_bytes_sent (sql_class.cc:4265)
==94390== by 0xC8EC46: net_real_write (net_serv.cc:730)
==94390== by 0xC8E0C8: net_flush (net_serv.cc:383)
==94390== by 0xC8E4D0: net_write_command (net_serv.cc:521)
==94390== by 0xADCE61: cli_advanced_command (client.c:468)
==94390== by 0xAE3CAF: mysql_close_slow_part (client.c:3671)
==94390== by 0xAE3D28: mysql_close (client.c:3683)
==94390== by 0x149E69A8: spider_db_mbase::disconnect() (spd_db_mysql.cc:2217)
==94390== by 0x1491EA26: spider_db_disconnect(st_spider_conn*) (spd_db_conn.cc:297)
==94390== by 0x14948EBE: spider_free_conn_alloc(st_spider_conn*) (spd_conn.cc:196)
==94390== by 0x1494B26A: spider_free_conn(st_spider_conn*) (spd_conn.cc:1251)
==94390== by 0x1494941F: spider_free_conn_from_trx(st_spider_transaction*, st_spider_conn*, bool, bool, int*) (spd_conn.cc:315)
==94390== Address 0x1f0e0990 is 4,832 bytes inside a block of size 25,728 free'd
==94390== at 0x4C2ACBD: free (vg_replace_malloc.c:530)
==94390== by 0x13F5545: my_free (my_malloc.c:222)
==94390== by 0x6C75B7: ilink::operator delete(void*, unsigned long) (sql_list.h:618)
==94390== by 0x77B9F6: THD::~THD() (sql_class.cc:1724)
==94390== by 0x1494FCE0: spider_bg_conn_action(void*) (spd_conn.cc:2580)
==94390== by 0x4E3DDD4: start_thread (in /usr/lib64/libpthread-2.17.so)
==94390== by 0x5FBFEAC: clone (in /usr/lib64/libc-2.17.so)
==94390== Block was alloc'd at
==94390== at 0x4C29BC3: malloc (vg_replace_malloc.c:299)
==94390== by 0x13F4DFA: my_malloc (my_malloc.c:101)
==94390== by 0x1491CF06: ilink::operator new(unsigned long) (sql_list.h:614)
==94390== by 0x1494F7FD: spider_bg_conn_action(void*) (spd_conn.cc:2501)
==94390== by 0x4E3DDD4: start_thread (in /usr/lib64/libpthread-2.17.so)
==94390== by 0x5FBFEAC: clone (in /usr/lib64/libc-2.17.so)
The used code is largely based on code from Tencent
The problem is that in some rare cases there may be a conflict between .frm
files and the files in the storage engine. In this case the DROP TABLE
was not able to properly drop the table.
Some MariaDB/MySQL forks has solved this by adding a FORCE option to
DROP TABLE. After some discussion among MariaDB developers, we concluded
that users expects that DROP TABLE should always work, even if the
table would not be consistent. There should not be a need to use a
separate keyword to ensure that the table is really deleted.
The used solution is:
- If a .frm table doesn't exists, try dropping the table from all storage
engines.
- If the .frm table exists but the table does not exist in the engine
try dropping the table from all storage engines.
- Update storage engines using many table files (.CVS, MyISAM, Aria) to
succeed with the drop even if some of the files are missing.
- Add HTON_AUTOMATIC_DELETE_TABLE to handlerton's where delete_table()
is not needed and always succeed. This is used by ha_delete_table_force()
to know which handlers to ignore when trying to drop a table without
a .frm file.
The disadvantage of this solution is that a DROP TABLE on a non existing
table will be a bit slower as we have to ask all active storage engines
if they know anything about the table.
Other things:
- Added a new flag MY_IGNORE_ENOENT to my_delete() to not give an error
if the file doesn't exist. This simplifies some of the code.
- Don't clear thd->error in ha_delete_table() if there was an active
error. This is a bug fix.
- handler::delete_table() will not abort if first file doesn't exists.
This is bug fix to handle the case when a drop table was aborted in
the middle.
- Cleaned up mysql_rm_table_no_locks() to ensure that if_exists uses
same code path as when it's not used.
- Use non_existing_Table_error() to detect if table didn't exists.
Old code used different errors tests in different position.
- Table_triggers_list::drop_all_triggers() now drops trigger file if
it can't be parsed instead of leaving it hanging around (bug fix)
- InnoDB doesn't anymore print error about .frm file out of sync with
InnoDB directory if .frm file does not exists. This change was required
to be able to try to drop an InnoDB file when .frm doesn't exists.
- Fixed bug in mi_delete_table() where the .MYD file would not be dropped
if the .MYI file didn't exists.
- Fixed memory leak in Mroonga when deleting non existing table
- Fixed memory leak in Connect when deleting non existing table
Bugs fixed introduced by the original version of this commit:
MDEV-22826 Presence of Spider prevents tables from being force-deleted from
other engines
To install Spider one can simply drop a /etc/mysql/conf.d/spider.cnf like
[mariadb]
plugin-load-add=ha_spider.so
This is automatically generated and installed when plugin is correctly
registered to plugin.cmake with its own component name. Many other plugins
such as Connect and RocksDB install in the same way.
This solved MDEV-19917 as the mere adding and removing of spider.cnf
automatically installs and uninstalls it.
Remove the overly complex and uncecessary install.sql from Spider,
if should not be needed in modern times anymore.
With this change there is no need for a uninstall.sql either.
reduce the amount of engine-specific code in the server,
particularly as it does not serve any purpose now.
may be needed for VP engine,
to be reconsidered in MDEV-7795
