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.
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
Fixed various bugs: setting local variables to NULL, SELECT INTO var now actually
might work, SELECT INTO with not row now gives a "no data" warning (instead of
the "empty query" error), etc.
Updated test cases accordingly.
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.
- when we don't have in_addr_t, use uint32.
- a forgotten initialization of slave_proxy_id in sql/log_event.cc (was not really "forgot", was
"we needn't init it there", but there was one case where we needed...).
- made slave_proxy_id always meaningful in THD and Log_event, so we can
rely more on it (no need to test if it's meaningful). THD::slave_proxy_id
is equal to THD::thread_id except for the slave SQL thread.
- clean up the slave's temporary table (i.e. free their memory) when slave
server shuts down.
New sp_cache C API. When an SP is dropped, old caches (in other threads)
become invalid and are cleared.
Also, the caches in THD are only created on demand.
WL#604 Privileges in embedded library
code added to check privileges in embedded library
NO_EMBEDDED_ACCESS_CHECKS macros inserted in code so we can exclude
access-checking parts. Actually we now can exclude these parts from
standalone server as well. Do we need it?
Access checks are disabled in embedded server by default. One should
edit libmysqld/Makefile manually to get this working.
We definitely need the separate configure for embedded server
embedded library
some dirty places cleaned:
uint removed from mysql.h as Miguel suggested
empty_string renamed as my_empty_string to get rid of name's intersections
using embedded library
