and remove usage of RESET MASTER in loops.
- Remove sleep of 0.1 second that was done even when not needed.
- Don't call include/wait_wsrep_ready.inc if NO_WSREP is defined.
- Added NO_WSREP=1 to all atomic tests.
- Use 'select 1' instead of 'show status' to check is server is up.
- Changed RESET MASTER to FLUSH BINARY LOGS to speed up atomic tests.
To be able to do this, added a new parameter variable to
show_events.inc to allow one to specify the name of the binary log
in the output.
Description of how DROP DATABASE works after this patch
- Collect list of tables
- DDL log tables as they are dropped
- DDL log drop database
- Delete db.opt
- Delete data directory
- Log either DROP TABLE or DROP DATABASE to binary log
- De active ddl log entry
This is in line of how things where before (minus ddl logging) except that
we delete db.opt file last to not loose it if DROP DATABASE fails.
On recovery we have to ensure that all dropped tables are logged in
binary log and that they are properly dropped (as with atomic drop
table).
No new tables be dropped as part of recovery.
Recovery of active drop database ddl log entry:
- If drop database was logged to ddl log but was not found in the binary
log:
- drop the db.opt file and database directory.
- Log DROP DATABASE to binary log
- If drop database was not logged to ddl log
- Update binary log with DROP TABLE of the dropped tables. If table list
is longer than max_allowed_packet, then the query will be split into
multiple DROP TABLE/VIEW queries.
Other things:
- Added DDL_LOG_STATE and 'current database' as arguments to
mysql_rm_table_no_locks(). This was needed to be able to combine
ddl logging of DROP DATABASE and DROP TABLE and make the generated
DROP TABLE statements shorter.
- To make the DROP TABLE statement created by ddl log shorter, I changed
the binlogged query to use current directory and omit the directory
part for all tables in the current directory.
- Merged some DROP TABLE and DROP VIEW code in ddl logger. This was done
to be able get separate DROP VIEW and DROP TABLE statements in the binary
log.
- Added a 'recovery_state' variable to remember the state of dropped
tables and views.
- Moved out code that drops database objects (stored procedures) from
mysql_rm_db_internal() to drop_database_objects() for better code reuse.
- Made mysql_rm_db_internal() global so that could be used by the ddl
recovery code.
Logging logic:
- Log tables, just before they are dropped, to the ddl log
- After the last table for the statement is dropped, log an xid for the
whole ddl log event
In case of crash:
- Remove first any active DROP TABLE events from the ddl log that matches
xids found in binary log (this mean the drop was successful and was
propery logged).
- Loop over all active DROP TABLE events
- Ensure that the table is completely dropped
- Write a DROP TABLE entry to the binary log with the dropped tables.
Other things:
- Added code to ha_drop_table() to be able to tell the difference if
a get_new_handler() failed because of out-of-memory or because the
handler refused/was not able to create a a handler. This was needed
to get sequences to work as sequences needs a share object to be passed
to get_new_handler()
- TC_LOG_BINLOG::recover() was changed to always collect Xid's from the
binary log and always call ddl_log_close_binlogged_events(). This was
needed to be able to collect DROP TABLE events with embedded Xid's
(used by ddl log).
- Added a new variable "$grep_script" to binlog filter to be able to find
only rows that matches a regexp.
- Had to adjust some test that changed because drop statements are a bit
larger in the binary log than before (as we have to store the xid)
Other things:
- MDEV-25588 Atomic DDL: Binlog query event written upon recovery is corrupt
fixed (in the original commit).