binlog coordinates corresponding to the dump".
The good news is that now mysqldump can be used to get an online backup of InnoDB *which works for
point-in-time recovery and replication slave creation*. Formerly, mysqldump --master-data --single-transaction
used to call in fact mysqldump --master-data, so the dump was not an online dump (took big lock all time of dump).
The only lock which is now taken in this patch is at the beginning of the dump: mysqldump does:
FLUSH TABLES WITH READ LOCK; START TRANSACTION WITH CONSISTENT SNAPSHOT; SHOW MASTER STATUS; UNLOCK TABLES;
so the lock time is in fact the time FLUSH TABLES WITH READ LOCK takes to return (can be 0 or very long, if
a table is undergoing a huge update).
I have done some more minor changes listed in the paragraph of mysqldump.c.
WL#2237 "WITH CONSISTENT SNAPSHOT clause for START TRANSACTION":
it's a START TRANSACTION which additionally starts a consistent read on all
capable storage engine (i.e. InnoDB). So, can serve as a replacement for
BEGIN; SELECT * FROM some_innodb_table LIMIT 1; which starts a consistent read too.
DROP DATABASE failed because of file ext not in TYPELIB of known extensions.
General solution - construct a TYPELIB at runtime instead of a static list.
column types TIMESTAMP is NOT NULL by default, so in order to have
TIMESTAMP column holding NULL valaues you have to specify NULL as
one of its attributes (this needed for backward compatibility).
Main changes:
Replaced TABLE::timestamp_default_now/on_update_now members with
TABLE::timestamp_auto_set_type flag which is used everywhere
for determining if we should auto-set value of TIMESTAMP field
during this operation or not. We are also use Field_timestamp::set_time()
instead of handler::update_timestamp() in handlers.
* Changed the implementation of ndbcluster_find_files to be more efficient, using only one mutex lock
* Moved ha_find_files to end of mysql_find_files so that it can be passed the list that we are interested to find.
* Renamed handler::estimate_number_of_rows to handler::estimate_rows_upper_bound function, which can also return "unknown"
* made filesort to use full sort buffer if number of rows to sort is not known.
added tests to alter table for "large" alter tables and truncates in ndbcluster
added debug printout in restart() in ndbcluster
added flag THD::transaction.on to enable/disable transaction
Set default max_allowed_packet to be able to read help tables even if an my.cnf file with this option is present. (Bug #3938)
Don't use default arguments for ha_rnd_init()
Simple code cleanups since last pull
a limitation of yesterday's implementation:
if there was an unfinished transaction (COMMIT not typed), and some MyISAM tables were
then updated, and then mysqld crashes, then at restart the server would use the too old
binlog offset known by InnoDB to cut the binlog, thus cutting the successful MyISAM
updates. We fix this by reporting the binlog offset into InnoDB even if InnoDB was not
affected at all by the update.
But the feature is still disabled until we decide if it can go into 4.1.3.
more logical table/index_flags
return HA_ERR_WRONG_COMMAND instead of abstract methods where appropriate
max_keys and other limits renamed to max_supported_keys/etc
max_keys/etc are now wrappers to max_supported_keys/etc
ha_index_init/ha_rnd_init/ha_index_end/ha_rnd_end are now wrappers to real {index,rnd}_{init,end} to enforce strict pairing
New records_in_range() interface (similar to read_range())
Macros for faster bitmap handling
Simplify read_range() code (#WL1786)
New general key_cmp() function to compare keys
- New solution after discussions with Sergei, no handler specific code or error messages should be in sql layer.
next_result, only check for error if check is -1
Improved index_read
HEAP: Copies the key count to a backup variable and sets the key count to zero.
That way, no HEAP function will ever try to touch any index.
Re-enabling is done by copying back the backup variable.
To avoid memory leak at table close, disable deletes all index trees.
Re-enabling must be done with empty indexes and data anyway. Otherwise,
the indexes would need to be repaired, wich HEAP is not capable of.
MyISAM: Only the key_map is cleared and set.
Re-enabling must be done with empty indexes and data. Otherwise, repair needs
to be done which will enable all keys persistently.
The former implementation disabled only non-unique keys and maked this persistent.
The new implementation additionally can disable all keys, but only without
making this persistent. Re-enabling all keys can be done without repair,
if data file and indexes are empty.