create_tmp_table()".
The fix for bug 21787 "COUNT(*) + ORDER BY + LIMIT returns wrong
result" introduced valgrind warnings which occured during execution
of information_schema.test and sp-prelocking.test in version 5.0.
There were no user visible effects.
The latter fix made create_tmp_table() dependant on
THD::lex::current_select value. Valgrind warnings occured when this
function was executed and THD::lex::current_select member pointed
to uninitialized SELECT_LEX instance.
This fix tries to remove this dependancy by moving some logic
outside of create_tmp_table() function.
Crash may happen when selecting from a merge table that has underlying
tables with less indexes than in a merge table itself.
If number of keys in merge table is not bigger than requested key number,
return error.
If mysqld is linked against system installed zlib (which is likely compiled w/o
LFS) and archive table exceedes 2G, mysqld will likely be terminated with SIGXFSZ.
Prior to actual write perform a check if there is space in data file. This fixes
abnormal process termination with SIGXFSZ.
No test case for this bugfix.
Deletes on a big index could crash the index when it needs to
shrink.
Put a forgotten negation operator in.
No test case. It is too big for the test suite. And it does not
work with 4.0, only with higher versions. It is attached to the
bug report.
The function receives an exactly-sized buffer (not a C NUL-terminated string)
and passes it into a printf function to be interpreted with "%s".
Instead, create an intermediate String object, and copy the data into it,
and pass in a pointer to the String's NUL-terminated buffer.
There was possible stack overrun in an edge case which handles invalid body of
a SP in mysql.proc . That should be case when mysql.proc has been changed
manually. Though, due to bug 21513, it can be exploited without having access
to mysql.proc only being able to create a stored routine.
Re-execution of a parametrized prepared statement or a stored routine
with a SELECT that use LEFT JOIN with second table having only one row
could yield incorrect result.
The problem appeared only for left joins with second table having only
one row (aka const table) and equation conditions in ON or WHERE clauses
that depend on the argument passed. Once the condition was false for
second const table, a NULL row was created for it, and any field involved
got NULL-value flag, which then was never reset.
The cause of the problem was that Item_field::null_value could be set
without being reset for re-execution. The solution is to reset
Item_field::null_value in Item_field::cleanup().
The STACK_MIN_SIZE is currently set to 8192, when we actually need
(emperically discovered) 9236 bytes to raise an fatal error, on Ubuntu
Dapper Drake, libc6 2.3.6-0ubuntu2, Linux kernel 2.6.15-27-686, on x86.
I'm taking that as a new lower bound, plus 100B of wiggle-room for sundry
word sizes and stack behaviors.
The added test verifies in a cross-platform way that there are no gaps
between the space that we think we need and what we actually need to report
an error.
DOCUMENTERS: This also adds "let" to the mysqltest commands that evaluate
an argument to expand variables therein. (Only right of the "=", of course.)