Before this patch mergeable derived tables / view used in a multi-table
update / delete were merged before the preparation stage.
When the merge of a derived table / view is performed the on expression
attached to it is fixed and ANDed with the where condition of the select S
containing this derived table / view. It happens after the specification of
the derived table / view has been merged into S. If the ON expression refers
to a non existing field an error is reported and some other mergeable derived
tables / views remain unmerged. It's not a problem if the multi-table
update / delete statement is standalone. Yet if it is used in a stored
procedure the select with incompletely merged derived tables / views may
cause a problem for the second call of the procedure. This does not happen
for select queries using derived tables / views, because in this case their
specifications are merged after the preparation stage at which all ON
expressions are fixed.
This patch makes sure that merging of the derived tables / views used in a
multi-table update / delete statement is performed after the preparation
stage.
Approved by Oleksandr Byelkin <sanja@mariadb.com>
First part of the fix (row0mysql.cc) addresses external columns when adding history
row on referential action. The full data must be retrieved before the
row is inserted.
Second part of the fix (the rest) avoids duplicate primary key error between
the history row generated on referential action and the history row
generated by SQL command. Both command and referential action can
happen on same table since foreign key can be self-reference (parent
and child tables are same). Moreover, the self-reference can refer
multiple rows when the key is non-unique. In such case history is
generated by referential action occured on first row but processed all
rows by a matched key. The second round is when the next row is
processed by a command but history already exists. In such case we
check TRX_ID of existing history row and if it is the same we assume
the above situation and skip adding one more history row or failing
the command.
Fixed by:
- Make all quick_* variable allocated according to real number keys instead
of MAX_KEY
- Store all the quick* items in separated allocated structure (OPT_RANGE)
- Ensure we don't access any quick* variable without first checking
opt_range_keys.is_set(). Thanks to this, we don't need any
pre-initialization of quick* variables anymore.
Some renames was done to use the new structure:
table->quick_keys -> table->opt_range_keys
table->quick_rows[X] -> table->opt_range[X].rows
table->quick_key_parts[X] -> table->opt_range[X].key_parts
table->quick_costs[X] -> table->opt_range[X].cost
table->quick_index_only_costs[X] -> table->opt_range[X].index_only_cost
table->quick_n_ranges[X] -> table->opt_range[X].ranges
table->quick_condition_rows -> table->opt_range_condition_rows
This patch should both decrease memory needed for TABLE objects
(3528 -> 984 + keyinfo) and increase performance, thanks to less
initializations per query, and more localized memory, thanks to the
opt_range structure.
MDEV-22531 Remove maria::implicit_commit()
MDEV-22607 Assertion `ha_info->ht() != binlog_hton' failed in
MYSQL_BIN_LOG::unlog_xa_prepare
From the handler point of view, Aria now looks like a transactional
engine. One effect of this is that we don't need to call
maria::implicit_commit() anymore.
This change also forces the server to call trans_commit_stmt() after doing
any read or writes to system tables. This work will also make it easier
to later allow users to have system tables in other engines than Aria.
To handle the case that Aria doesn't support rollback, a new
handlerton flag, HTON_NO_ROLLBACK, was added to engines that has
transactions without rollback (for the moment only binlog and Aria).
Other things
- Moved freeing of MARIA_SHARE to a separate function as the MARIA_SHARE
can be still part of a transaction even if the table has closed.
- Changed Aria checkpoint to use the new MARIA_SHARE free function. This
fixes a possible memory leak when using S3 tables
- Changed testing of binlog_hton to instead test for HTON_NO_ROLLBACK
- Removed checking of has_transaction_manager() in handler.cc as we can
assume that as the transaction was started by the engine, it does
support transactions.
- Added new class 'start_new_trans' that can be used to start indepdendent
sub transactions, for example while reading mysql.proc, using help or
status tables etc.
- open_system_tables...() and open_proc_table_for_Read() doesn't anymore
take a Open_tables_backup list. This is now handled by 'start_new_trans'.
- Split thd::has_transactions() to thd::has_transactions() and
thd::has_transactions_and_rollback()
- Added handlerton code to free cached transactions objects.
Needed by InnoDB.
squash! 2ed35999f2a2d84f1c786a21ade5db716b6f1bbc
All changes (except one) is of type
thd->transaction. -> thd->transaction->
thd->transaction points by default to 'thd->default_transaction'
This allows us to 'easily' have multiple active transactions for a
THD object, like when reading data from the mysql.proc table
even if we're *allowed to* convert DELETE .. FOR PERIOD OF
into an update internally, doesn't think we'll *be able to*.
We always have to prepare for insert.
`inited == NONE` at the initialization time does not always mean
that it'll be `NONE` later, at the execution time. Use a more complex
caller-specific logic to decide whether to create a cloned lookup handler.
Besides LOAD (as in the original bug report) make sure that all
prepare_for_insert() invocations are covered by tests. Add tests for
CREATE ... SELECT, multi-UPDATE, and multi-DELETE.
Don't enable write cache with long uniques.
* rename to a generic name
* move remaning initializations from query exec to prepare time
* simplify/unify key handling in open_table_from_share and delayed
* remove dead code
* move tests where they belong
MDEV-21606 Improve update handler (long unique keys on blobs)
MDEV-21470 MyISAM and Aria start_bulk_insert doesn't work with long unique
MDEV-21606 Bug fix for previous version of this code
MDEV-21819 2 Assertion `inited == NONE || update_handler != this'
- Move update_handler from TABLE to handler
- Move out initialization of update handler from ha_write_row() to
prepare_for_insert()
- Fixed that INSERT DELAYED works with update handler
- Give an error if using long unique with an autoincrement column
- Added handler function to check if table has long unique hash indexes
- Disable write cache in MyISAM and Aria when using update_handler as
if cache is used, the row will not be inserted until end of statement
and update_handler would not find conflicting rows.
- Removed not used handler argument from
check_duplicate_long_entries_update()
- Syntax cleanups
- Indentation fixes
- Don't use single character indentifiers for arguments
Wrong assertion condition. SYSTEM_TIME_ALL indicates that
vers_setup_conds() is done. In case FOR SYSTEM_TIME ALL is specified
in command the assertion passes but not checks anything.
MDEV-18957 UPDATE with LIMIT clause is wrong for versioned partitioned tables
UPDATE, DELETE: replace linear search of current/historical records
with vers_setup_conds().
Additional DML cases in view.test
Count the "gap" time between table accesses and display it as
r_other_time_ms in the "table" element.
* The advantage of this approach is that it doesn't add any new
my_timer_cycles() calls.
* The disadvantage is that the definition of what is done during
"other time" is not that clear: it includes checking the WHERE
(for this table), constructing index lookup tuple (for the next table)
writing to GROUP BY temporary table (as we dont account for that time
separately [yet], etc)
- Any temporary tables created under read-only mode will never be logged
to binary log. Any usage of these tables to update normal tables, even
after read-only has been disabled, will use row base logging (as the
temporary table will not be on the slave).
- Analyze, check and repair table will not be logged in read-only mode.
Other things:
- Removed not used varaibles in
MYSQL_BIN_LOG::flush_and_set_pending_rows_event.
- Set table_share->table_creation_was_logged for all normal tables.
- THD::binlog_query() now returns -1 if statement was not logged., This
is used to update table_share->table_creation_was_logged.
- Don't log admin statements in opt_readonly is set.
- Table's that doesn't have table_creation_was_logged will set binlog format to row
logging.
- Removed not needed/wrong setting of table->s->table_creation_was_logged
in create_table_from_items()
because internally setup_wild() adjusts select_lex->with_wild directly
anyway, so there is no reason to pretend that the number of '*' may be
anything else but select_lex->with_wild
And don't update select_lex->item_list, because fields can come
from anywhere and don't necessarily have to be copied into select_lex.
Now both offset and limit are stored and do not chenged during execution
(offset is decreased during processing in versions before 10.5).
(Big part of this changes made by Monty)
* Made make_versioned_*() proxies inline;
* Renamed truncate_history to delete_history
Part of:
MDEV-19814 Server crash in row_upd_del_mark_clust_rec or Assertion
`update->n_fields < ulint(table->n_cols + table->n_v_cols)' failed in
upd_node_t::make_versioned_helper
Analysis
========
Point in time recovery using mysqlbinlog containing queries
operating on temporary tables results in an error.
While writing the query log event in the binary log, the
thread id used for execution of DROP TABLE and DELETE commands
were incorrect. The thread variable 'thread_specific_used'
is used to determine whether a specific thread id is to used
while executing the statements i.e using 'SET
@@session.pseudo_thread_id'. This variable was not set
correctly for DROP TABLE query and was never set for DELETE
query. The thread id is important for temporary tables
since the tables are session specific. DROP TABLE and DELETE
queries executed using a wrong thread id resulted in errors
while applying the queries generated by mysqlbinlog utility.
Fix
===
Set the 'thread_specific_used' THD variable for DROP TABLE and
DELETE queries.
ReviewBoard: 21833
