This is the main commit for Worklog tasks:
* A more dynamic binlog format which allows small changes (1064)
* Log session variables in Query_log_event (1063)
Below 5.0 means 5.0.0.
MySQL 5.0 is able to replicate FOREIGN_KEY_CHECKS, UNIQUE_KEY_CHECKS (for speed),
SQL_AUTO_IS_NULL, SQL_MODE. Not charsets (WL#1062), not some vars (I can only think
of SQL_SELECT_LIMIT, which deserves a special treatment). Note that this
works for queries, except LOAD DATA INFILE (for this it would have to wait
for Dmitri's push of WL#874, which in turns waits for the present push, so...
the deadlock must be broken!). Note that when Dmitri pushes WL#874 in 5.0.1,
5.0.0 won't be able to replicate a LOAD DATA INFILE from 5.0.1.
Apart from that, the new binlog format is designed so that it can tolerate
a little variation in the events (so that a 5.0.0 slave could replicate a
5.0.1 master, except for LOAD DATA INFILE unfortunately); that is, when I
later add replication of charsets it should break nothing. And when I later
add a UID to every event, it should break nothing.
The main change brought by this patch is a new type of event, Format_description_log_event,
which describes some lengthes in other event types. This event is needed for
the master/slave/mysqlbinlog to understand a 5.0 log. Thanks to this event,
we can later add more bytes to the header of every event without breaking compatibility.
Inside Query_log_event, we have some additional dynamic format, as every Query_log_event
can have a different number of status variables, stored as pairs (code, value); that's
how SQL_MODE and session variables and catalog are stored. Like this, we can later
add count of affected rows, charsets... and we can have options --don't-log-count-affected-rows
if we want.
MySQL 5.0 is able to run on 4.x relay logs, 4.x binlogs.
Upgrading a 4.x master to 5.0 is ok (no need to delete binlogs),
upgrading a 4.x slave to 5.0 is ok (no need to delete relay logs);
so both can be "hot" upgrades.
Upgrading a 3.23 master to 5.0 requires as much as upgrading it to 4.0.
3.23 and 4.x can't be slaves of 5.0.
So downgrading from 5.0 to 4.x may be complicated.
Log_event::log_pos is now the position of the end of the event, which is
more useful than the position of the beginning. We take care about compatibility
with <5.0 (in which log_pos is the beginning).
I added a short test for replication of SQL_MODE and some other variables.
TODO:
- after committing this, merge the latest 5.0 into it
- fix all tests
- update the manual with upgrade notes.
"EE_ error codes (EE_DELETE, EE_WRITE) end up in the binlog, making slave stop".
The problem was that during execution of the command on the master, an error
can occur (for example, not space left on device, then mysqld waits and when
there is space it completes successfully: so finally it worked but the error
EE_WRITE remains in thd->net.last_errno and thd->net.last_error).
To know if finally the command succeeded, we test the 'error' variable in
every place, and if it shows no failure we reset thd->net.last_err* using
the function THD::clear_error() which is backported from 4.1.
A new test to see if now only real errors get to the binlog (note: the test
uses "rm").
Also a bit of memory free/alloc saving in log_event.cc (do not free the whole
mem_root after every query in the slave SQL thread: we can keep the initial
block of it; which will be freed when the thread terminates).
Don't dump data for MRG_ISAM or MRG_MYISAM tables. (Bug #1846)
Ensure that 'lower_case_table_names' is always set on case insensitive file systems. (Bug #1812)
One can now configure MySQL as windows service as a normal user. (Bug #1802)
Database names is now compared with lower case in ON clause when lower_case_table_names is set. (Bug #1736)
IGNORE ... LINES option didn't work when used with fixed length rows. (Bug #1704)
Change INSERT DELAYED ... SELECT... to INSERT .... SELECT (Bug #1983)
Safety fix for service 'mysql start' (Bug #1815)
we change THD::system_thread from a 'bool' to a bitmap to be able to
distinguish between delayed-insert threads and slave threads.
- Fix for BUG#1701 "Update from multiple tables" (one line in sql_parse.cc,
plus a new test rpl_multi_update.test). That's just adding an initialization.
Fixed compiler warnings (a lot of hidden variables detected by the Forte compiler)
Added a lot of 'version_xxx' strings to 'show variables'
Prevent copying of TMP_TABLE_PARAM (This caused core dump bug on Solaris)
Fixed problem with printing sub selects to debug log
- unused variable THD::con_root removed
- we don't need to bzero(&warn_root) just before init_alloc_root(&warn_root)
- we don't need to bzero(&transaction.mem_root) because we
bzero(&transaction) later in THD::THD
- we don't need to free thd->mem_root thd->transaction.mem_root
in handle_one_connection because they are freed in THD::~THD
which is called in end_thread later
Cleaned up (and disabled part of) date/time/datetime format patch. One can't anymore change default read/write date/time/formats.
This is becasue the non standard datetime formats can't be compared as strings and MySQL does still a lot of datetime comparisons as strings
Changed flag argument to str_to_TIME() and get_date() from bool to uint
Removed THD from str_to_xxxx functions and Item class.
Fixed core dump when doing --print-defaults
Move some common string functions to strfunc.cc
Dates as strings are now of type my_charset_bin instead of default_charset()
Introduce IDENT_QUOTED to not have to create an extra copy of simple identifiers (all chars < 128)
Removed xxx_FORMAT_TYPE enums and replaced them with the old TIMESTAMP_xxx enums
Renamed some TIMESTAMP_xxx enums to more appropriate names
Use defines instead of integers for date/time/datetime string lengths
Added to build system and use the new my_strtoll10() function.
query_alloc_block_size, query_prealloc_size, range_alloc_block_size,transaction_alloc_block_size and transaction_prealloc_size
Add more checks for "out of memory" detection in range optimization
Prepared statements in embedded server
Several changes in library code with two goals:
to make mysql_prepare_stmt working in embedded server
to get rid of #define mysql_interface_func mysql->methods->interface_func
in user's interface
