The problem is that the C API function mysql_real_connect
only attempts to connect to the first IP address returned
for a hostname. This can be a problem if a hostname maps
to multiple IP address and the server is not bound to the
first one that is returned.
The solution is to augment mysql_real_connect so that it
attempts to connect to all IPv4 addresses that a domain
name maps to. The function goes over the list of address
until a successful connection is established.
No test case is provided as its not possible to test this
automatically with the current testing infrastructure.
Backport to MySQL 5.0/1 fix by Vladislav Vaintroub:
In Vista and later and also in when using terminal services, when
server is started from command line, client cannot connect to it
via shared memory protocol.
This is a regression introduced when Bug#24731 was fixed. The
reason is that client is trying to attach to shared memory using
global kernel object namespace (all kernel objects are prefixed
with Global\). However, server started from the command line in
Vista and later will create shared memory and events using current
session namespace. Thus, client is unable to find the server and
connection fails.
The fix for the client is to first try to find server using "local"
names (omitting Global\ prefix) and only if server is not found,
trying global namespace.
in load_defaults()
load_defaults(), my_search_option_files() and
my_print_default_files() utilized a global variable
containing a pointer to thread local memory. This could lead
to race conditions when those functions were called with high
concurrency.
Fixed by changing the interface of the said functions to avoid
the necessity for using a global variable.
Since we cannot change load_defaults() prototype for API
compatibility reasons, it was renamed my_load_defaults().
Now load_defaults() is a thread-unsafe wrapper around
a thread-safe version, my_load_defaults().
Bug#38435 - LONG Microseconds cause MySQL to fail a CAST to DATETIME or DATE
Parsing of optional microsecond part in datetime did not
fail gracefully when field width was larger than the allowed
six places.
Now handles up to the correct six places, and disregards
any extra digits without messing up what we've already got.
- Remove bothersome warning messages. This change focuses on the warnings
that are covered by the ignore file: support-files/compiler_warnings.supp.
- Strings are guaranteed to be max uint in length
- Remove bothersome warning messages. This change focuses on the warnings
that are covered by the ignore file: support-files/compiler_warnings.supp.
- Strings are guaranteed to be max uint in length
Passing dubious "year zero" in non-zero date (not "0000-00-00") could
lead to negative value for year internally, while variable was unsigned.
This led to Really Bad Things further down the line.
Now doing calculations with signed type for year internally.
When linking with some external programs, "multiple definition
of `init_time'"
Rename init_time() to my_init_time() to avoid collision with other
libraries (particularly libmng).
The problem was that the COM_STMT_SEND_LONG_DATA was sending a response
packet if the prepared statement wasn't found in the server (due to
reconnection). The commands COM_STMT_SEND_LONG_DATA and COM_STMT_CLOSE
should not send any packets, even error packets should not be sent since
they are not expected by the client API.
The solution is to clear generated during the execution of the aforementioned
commands and to skip resend of prepared statement commands. Another fix is
that if the connection breaks during the send of prepared statement command,
the command is not sent again since the prepared statement is no longer in the
server.
in some case.
ER_CON_COUNT_ERROR is defined with SQL state 08004. However, this SQL state is not always
returned.
This error can be thrown in two cases:
1. when an ordinary user (a user w/o SUPER privilege) is connecting,
and the number of active user connections is equal or greater than
max_connections.
2. when a user is connecting and the number of active user connections is
already (max_connections + 1) -- that means that no more connections will
be accepted regardless of the user credentials.
In the 1-st case, SQL state is correct.
The bug happens in the 2-nd case -- on UNIX the client gets 00000 SQL state, which is
absolutely wrong (00000 means "not error SQL state); on Windows
the client accidentally gets HY000 (which means "unknown SQL state).
The cause of the problem is that the server rejects extra connection
prior to read a packet with client capabilities. Thus, the server
does not know if the client supports SQL states or not (if the client
supports 4.1 protocol or not). So, the server supposes the worst and
does not send SQL state at all.
The difference in behavior on UNIX and Windows occurs because on Windows
CLI_MYSQL_REAL_CONNECT() invokes create_shared_memory(), which returns
an error (in default configuration, where shared memory is not configured).
Then, the client does not reset this error, so when the connection is
rejected, SQL state is HY000 (from the error from create_shared_memory()).
The bug appeared after test case for Bug#33507 -- before that, this behavior
just had not been tested.
The fix is to 1) reset the error after create_shared_memory();
2) set SQL state to 'unknown error' if it was not received from
the server.
A separate test case is not required, since the behavior is already
tested in connect.test.
Note for doc-team: the manual should be updated to say that under
some circumstances, 'Too many connections' has HY000 SQL state.
Rename client_last_error to last_error and client_last_errno to last_errno
to not break connectors which use the internal net structure for error handling.
There was no way to return an error from the client library
if no MYSQL connections was established.
So here i added variables to store that king of errors and
made functions like mysql_error(NULL) to return these.
--local-infile=0 checks can be bypassed by sending a FETCH LOCAL FILE response
Add a check for CLIENT_LOCAL_FILES before sending a local file.
Beware, that all binary distributions enable sending of local files and it's up
to the programs which use libmysql to disable it, if they don't use this functionality.
Otherwise they are not safe.
The problem is that one can not create a stored routine if sql_mode
contains NO_ENGINE_SUBSTITUTION or PAD_CHAR_TO_FULL_LENGTH. Also when
a event is created, the mode is silently lost if sql_mode contains one
of the aforementioned. This was happening because the table definitions
which stored sql_mode values weren't being updated to accept new values
of sql_mode.
The solution is to update, in a backwards compatible manner, the various
table definitions (columns) that store the sql_mode value to take into
account the new possible values. One incompatible change is that if a event
that is being created can't be stored to the mysql.event table, an error
will be raised.
The tests case also ensure that new SQL modes will be added to the mysql.proc
and mysql.event tables, otherwise the tests will fail.
cause ROLLBACK of statement", part 1. Review fixes.
Do not send OK/EOF packets to the client until we reached the end of
the current statement.
This is a consolidation, to keep the functionality that is shared by all
SQL statements in one place in the server.
Currently this functionality includes:
- close_thread_tables()
- log_slow_statement().
After this patch and the subsequent patch for Bug#12713, it shall also include:
- ha_autocommit_or_rollback()
- net_end_statement()
- query_cache_end_of_result().
In future it may also include:
- mysql_reset_thd_for_next_command().
This is a regression from 2007-05-18 when code to zero out the returned struct was
added to number_to_datetime(); zero for time_type corresponds to MYSQL_TIMESTAMP_DATE.
We now explicitly set the type we return (MYSQL_TIMESTAMP_DATETIME).
BETWEEN was more lenient with regard to what it accepted as a DATE/DATETIME
in comparisons than greater-than and less-than were. ChangeSet makes < >
comparisons similarly robust with regard to trailing garbage (" GMT-1")
and "missing" leading zeros. Now all three comparators behave similarly
in that they throw a warning for "junk" at the end of the data, but then
proceed anyway if possible. Before < > fell back on a string- (rather than
date-) comparison when a warning-condition was raised in the string-to-date
conversion. Now the fallback only happens on actual errors, while warning-
conditions still result in a warning being to delivered to the client.
