Several system variables did not behave like system variables should do.
When trying to SET them or use them in SELECT, they were reported as
"unknown system variable". But they appeared in SHOW VARIABLES.
This has been fixed by removing the "fixed_vars" array of variables
and integrating the variables into the normal system variables chain.
All of these variables do now behave as read-only global-only
variables. Trying to SET them tells they are read-only, trying to
SELECT the session value tells they are global only. Selecting the
global value works. It delivers the same value as SHOW VARIABLES.
set but is ignored".
This patch makes @@session.max_allowed_packed and
@@session.net_buffer_length read-only as suggested in the bug
report. The user will have to use SET GLOBAL (and reconnect)
to alter the session values of these variables.
The error string ER_VARIABLE_IS_READONLY is introduced.
Tests are modified accordingly.
We have "set" variables, which can accept empty values
(like sql_mode), and which can not (like log_output). The problem
was that the code does not distinguish them and allow empty
values for every set variable.
The fix is to introduce an attribute of a set variable telling
whether it can accept empty values.
Default values of variables were not subject to upper/lower bounds
and step, while setting variables was. Bounds and step are also
applied to defaults now; defaults are corrected quietly, values
given by the user are corrected, and a correction-warning is thrown
as needed. Lastly, very large values could wrap around, starting
from 0 again. They are bounded at the maximum value for the
respective data-type now if no lower maximum is specified in the
variable's definition.
doesn't recognize it
This is a 5.0 version of the patch, it will be null-merged to 5.1
Problem:
'log' and 'log_slow_queries' were "fixed" variables, i.e. they showed up
in SHOW VARIABLES, but could not be used in expressions like
"select @@log". Also, using them in the SET statement produced an
incorrect "unknown system variable" error.
Solution:
Make 'log' and 'log_slow_queries' read-only dynamic variables to make
them available for use in expressions, and produce a correct error
about the variable being read-only when used in the SET statement.
Buffer used when setting variables was not dimensioned to accomodate
trailing '\0'. An overflow by one character was therefore possible.
CS corrects limits to prevent such overflows.
This is for bug #29446 "Specifying a myisam_sort_buffer > 4GB on 64 bit machines not possible". Support for myisam_sort_buffer_size > 4 GB on 64-bit Windows will be looked at later in 5.2.
Moved duplicated code to inline function store_timestamp()
Save thd->time_zone_used when logging to table as CSV internally cases it to be changed
Added MYSQL_LOCK_IGNORE_FLUSH to log tables to avoid deadlock in case of flush tables.
Mark log tables with TIMESTAMP_NO_AUTO_SET to avoid automatic timestamping
Set TABLE->no_replicate on open
--long-query-time is now given in seconds with microseconds as decimals
--min_examined_row_limit added for slow query log
long_query_time user variable is now double with 6 decimals
Added functions to get time in microseconds
Added faster time() functions for system that has gethrtime() (Solaris)
We now do less time() calls.
Added field->in_read_set() and field->in_write_set() for easier field manipulation by handlers
set_var.cc and my_getopt() can now handle DOUBLE variables.
All time() calls changed to my_time()
my_time() now does retry's if time() call fails.
Added debug function for stopping in mysql_admin_table() when tables are locked
Some trivial function and struct variable renames to avoid merge errors.
Fixed compiler warnings
Initialization of some time variables on windows moved to my_init()
Problem: setting/displaying @@LC_TIME_NAMES didn't distinguish between
GLOBAL and SESSION variable types - always SESSION variable
was set/shonw.
Fix: set either global or session value.
Also, "mysqld --lc-time-names" was added to set "global default" value.
"Server Variables for Plugins"
Implement support for plugins to declare server variables.
Demonstrate functionality by removing InnoDB specific code from sql/*
New feature for HASH - HASH_UNIQUE flag
New feature for DYNAMIC_ARRAY - initializer accepts preallocated ptr.
Completed support for plugin reference counting.
Problem: replication of LC_TIME_NAMES didn't work.
Thus, INSERTS or UPDATES using date_format() always
worked with en_US on the slave side.
Fix: adding ONE_SHOT implementation for LC_TIME_NAMES.
Zero-length variables caused failures when using the length to look
up the name in a hash. Instead, signal that no zero-length name can
ever be found and that to encounter one is a syntax error.
Bug #19606: ssl variables are not displayed in show variables
Bug #19616: log_queries_not_using_indexes is not listed in show variables
Make basedir, datadir, tmpdir, log_queries_not_using_indexes, ssl_ca,
ssl_capath, ssl_cert, ssl_cipher, and ssl_key all available both from
SHOW VARIABLES and as @@variables.
As a side-effect of this change, log_queries_not_using_indexes can
be changed at runtime (but only globally, not per-connection).
