is inconsistent
+ several improvements
Details:
- The subtest with assignment of floating point numbers to
DECIMAL parameters in functions and procedures checks
now that the final DECIMAL value is the same as if we assign
the floating point numbers to columns, user variables etc.
= The impact of math libs or truncation must be the same.
- Remove storage engine variants of this test because the
stored procedure properties tested do not depend on
the storage engine.
Use the fastest storage engine (MEMORY) for any tables
needed.
- reset global sort_buffer_size to startup value
- Partially improved formatting.
When analyzing the possible index use cases the server was re-using an internal structure.
This is wrong, as this internal structure gets updated during the analysis.
Fixed by making a copy of the internal structure for every place it needs to be used.
Also stopped the generation of empty SEL_TREE structures that unnecessary
complicate the analysis.
Bug#37536: Thread scheduling causes performance degradation at low thread count
Deprecated --skip-thread-priority startup option as newer versions of
the server won't change the thread priorities by default.
Giving threads different priorities might yield marginal improvements
in some platforms (where it actually works) but on the other hand it
might cause significant degradation depending on the thread count and
number of processors. Meddling with the thread priorities is a not a
safe bet as it is very dependent on the behavior of the cpu scheduler
and system where MySQL is being run.
From MySQL 6.0 and up the default behavior is that of not modifying
the threads priorities.
This patch contains fixes for two problems:
1. As originally reported, the server crashed on Mac OS X when trying to access
an EXAMPLE table after the EXAMPLE plugin was installed.
It turned out that the dynamically loaded EXAMPLE plugin called the
function hash_earch() from a Mac OS X system library, instead of
hash_earch() from MySQL's mysys library. Makefile.am in storage/example
does not include libmysys. So the Mac OS X linker arranged the hash_search()
function to be linked to the system library when the shared object is
loaded.
One possible solution would be to include libmysys into the linkage of
dynamic plugins. But then we must have a libmysys.so, which must be
used by the server too. This could have a minimal performance impact,
but foremost the change seems to bee too risky at the current state of
MySQL 5.1.
The selected solution is to rename MySQL's hash_search() to my_hash_search()
like it has been done before with hash_insert() and hash_reset().
Since this is the third time, we need to rename a hash_*() function,
I did renamed all hash_*() functions to my_hash_*().
To avoid changing a zillion calls to these functions, and announcing
this to hundreds of developers, I added defines that map the old names
to the new names.
This change is in hash.h and hash.c.
2. The other problem was improper implementation of the handlerton-to-plugin
mapping. We use a fixed-size array to hold a plugin reference for each
handlerton. On every install of a handler plugin, we allocated a new slot
of the array. On uninstall we did not free it. After some uninstall/install
cycles the array overflowed. We did not check for overflow.
One fix is to check for overflow to stop the crashes.
Another fix is to free the array slot at uninstall and search for a free slot
at plugin install.
This change is in handler.cc.
from stored procedure.
Problem: we replace all references to local variables in stored procedures
with NAME_CONST(name, value) logging to the binary log. However, if the
value's collation differs we might get an 'illegal mix of collation'
error as we don't pass the collation to the function.
Fix: pass the value's collation to NAME_CONST().
Note: actually we should pass to NAME_CONST() the value's derivation as well.
It's impossible without the parser modifying. Now we always set the
derivation to DERIVATION_IMPLICIT, the same as local variables have.
Server created "arc" directories inside database directories and
maintained there useless copies of .frm files.
Creation and renaming procedures of those copies as well as
creation of "arc" directories has been discontinued.
Removal procedure has been kept untouched to be able to
cleanup existent database directories by the DROP DATABASE
query. Also view renaming procedure has been updated to remove
these directories.
JOIN for the subselect wasn't cleaned if we came upon an error
during sub_select() execution. That leads to the assertion failure
in close_thread_tables()
part of the 6.0 code backported
per-file comments:
mysql-test/r/sp-error.result
Bug#37949 Crash if argument to SP is a subquery that returns more than one row
test result
mysql-test/t/sp-error.test
Bug#37949 Crash if argument to SP is a subquery that returns more than one row
test case
sql/sp_head.cc
Bug#37949 Crash if argument to SP is a subquery that returns more than one row
lex->unit.cleanup() call added if not substatement
The problem is that when statement-based replication was enabled,
statements such as INSERT INTO .. SELECT FROM .. and CREATE TABLE
.. SELECT FROM need to grab a read lock on the source table that
does not permit concurrent inserts, which would in turn be denied
if the source table is a log table because log tables can't be
locked exclusively.
The solution is to not take such a lock when the source table is
a log table as it is unsafe to replicate log tables under statement
based replication. Furthermore, the read lock that does not permits
concurrent inserts is now only taken if statement-based replication
is enabled and if the source table is not a log table.
In order to improve the performance when replicating to partitioned
myisam tables with row-based format, the number of rows of current
rows log event is estimated and used to setup storage engine for bulk
inserts.
Machines with hostname set to "localhost" cause uniqueness errors in
the SQL bootstrap data.
Now, insert zero lines for cases where the (lowercased) hostname is
the same as an already-inserted 'localhost' name. Also, fix a few tests
that expect certain local accounts to have a certain host name.
