bk resolve

-DDONT_USE_DEFAULT_FIELDS compile option.)

@item

MySQL allows you to store some wrong date values into

@code{DATE} and @code{DATETIME} columns (like 2000-02-31 or 2000-02-00).

If the date is totally wrong, MySQL Server will store the special

0000-00-00 date value in the column.

MySQL allows you to store some wrong date values into @code{DATE} and

@code{DATETIME} columns (like 2000-02-31 or 2000-02-00).  The idea is

that it's not the SQL server job to vaildate date.  If MySQL can store a

date and retrieve exactly the same date, then MySQL will store the

date. If the date is totally wrong (outside of MySQL abilty to store

it), MySQL Server will store the special 0000-00-00 date value in the

column.

@item

If you set an @code{ENUM} column to an unsupported value, it will be set to

@code{--skip-external-locking} and @code{--enable-locking} to

@code{--external-locking}.

@item

mysqld now has the option @code{--temp-pool} enabled by default as this

gives better performance with some OS.

@item

@code{DOUBLE} and @code{FLOAT} columns now honour the

@code{UNSIGNED} flag on storage (before, @code{UNSIGNED} was ignored for

these columns).

Note: in Version 4.0, @code{WEEK(#,0)} was changed to match the

calendar in the USA.

Note that if a week is the last week of the previous year, MySQL will

return 0:

@example

mysql> SELECT YEAR('2000-01-01'), WEEK('2000-01-01',0);

        -> 2000, 0

@end example

One could argue that MySQL should return @code{52} for the @code{WEEK()}

function as the given date is actually the 52 second week of 1999.  We

decided to return 0 instead as we want the function to return 'the week

number in the given year'.  This makes the usage of the @code{WEEK()}

function reliable when combined with other functions that extracts a

date part from a date.

If you would prefer to know the correct year-week, then you should use

the @code{YEARWEEK()} function instead:

@example

mysql> SELECT YEARWEEK('2000-01-01');

        -> 199952

mysql> SELECT MID(YEARWEEK('2000-01-01'),5,2);

        -> 52

@end example

@findex YEAR()

@item YEAR(date)

Returns the year for @code{date}, in the range @code{1000} to @code{9999}:

        -> 198653

@end example

Note that the week number is different from what the @code{WEEK()} function

would return (@code{0}) as the week function returns the week in the

context of the given year.

@findex HOUR()

@item HOUR(time)

Returns the hour for @code{time}, in the range @code{0} to @code{23}:

a string and performs a string comparison.  It does not convert

@code{'19970505'} to a date and perform a date comparison.

Note that MySQL does no checking whether the date is

Note that MySQL does very limited checking whether the date is

correct.  If you store an incorrect date, such as @code{'1998-2-31'}, the

wrong date will be stored. If the date cannot be converted to any reasonable

value, a @code{0} is stored in the @code{DATE} field.  This is mainly a speed

issue and we think it is up to the application to check the dates, and not

the server.

wrong date will be stored.

Because MySQL packs dates for storage, it can't store any given date as

it would not fit onto the result buffer. The rules for accepting a date

are:

@itemize @bullet

@item

If MySQL can store it and retrieve a date, the wrong date is accepted

for @code{DATE} and @code{DATETIME} columns.

@item

All days values between 0-31 are accepted for any date.  This makes it

very convenient for web applications where you ask year, month and day

in 3 different fields.

@item

The day or month field may be zero.  This is convenient if you want

to store a birthdate in a @code{DATE} column and you only know part

of the date.

@end itemize

If the date cannot be converted to any reasonable value, a @code{0} is

stored in the @code{DATE} field, which will be retrieved as

@code{0000-00-00}.  This is both a speed and convinient issue as we

belive that the databases responsiblity etrive the same date you stored

(even if the data was not logicall correct in all cases). We think it is

up to the application to check the dates, and not the server.

@node Problems with NULL, Problems with alias, Using DATE, Query Issues

@appendixsubsec Problems with @code{NULL} Values

@item

Fixed create table from any ITEM_FUNC and reverted a patch for month()

@item

mysqld now has the option @code{--temp-pool} enabled by default as this

gives better performance with some OS.

@item

Big code cleanup in replication code.

@item

If one specifies @code{--code-file}, call @code{setrlmit()} to change allowed

@appendixsubsec Changes in release 3.23.52

@itemize @bullet

@item

Fixed  a security bug with empty db column in db table

@item

Changed initialisation of @code{RND()} to make it less predicatable.

@item

Fixed problem with @code{GROUP BY} on result with expression that created a

@code{BLOB} field.

@item

Fixed problem with privilege tables when downgrading from 4.0.2 to 3.23.

@item

Fixed thread bug in @code{SLAVE START}, @code{SLAVE STOP} and automatic repair

of MyISAM tables that could cause table cache to be corrupted.

@item

Fixed possible thread related key-cache-corruption problem with

@code{OPTIMIZE TABLE} and @code{REPAIR TABLE}.

@item

Added name of 'administrator command' logs.

@item

Fixed bug with creating an auto-increment value on second part of a

@code{UNIQUE()} key where first part could contain NULL values.

@item

@item

Fixed bug with slave net read timeouting

@item

Fixed bug in ALTERing  TABLE of BDB type.

Fixed a core-dump bug with @code{MERGE} tables and @code{MAX()} function.

@item

Fixed bug in @code{ALTER TABLE} with BDB tables.

@item

Fixed bug when logging @code{LOAD DATA INFILE} to binary log with no 

active database.

#########################################################################

dnl Checks for library functions.

#

# The following code disables intrinsic function support while we test for

# library functions.  This is to avoid configure problems with Intel ecc

# compiler

ORG_CFLAGS="$CFLAGS"

if test "$GCC" != "yes"; then

  AC_SYS_COMPILER_FLAG(-nolib_inline,nolib_inline,CFLAGS,[],[])

fi

AC_FUNC_MMAP

AC_TYPE_SIGNAL

MYSQL_TYPE_QSORT

 pthread_condattr_create rwlock_init pthread_rwlock_rdlock \

 fchmod getpass getpassphrase initgroups mlockall)

CFLAGS="$ORG_CFLAGS"

# Sanity check: We chould not have any fseeko symbol unless

# large_file_support=yes

AC_CHECK_FUNCS(fseeko,

/* #define _AIX32_CURSES */	/* XXX: this breaks AIX 4.3.3 (others?). */

#endif

#ifdef __QNXNTO__

#define HAVE_ERRNO_AS_DEFINE

#define HAVE_FCNTL_LOCK

#undef  HAVE_SYS_UN_H

#undef  HAVE_FINITE

#undef  HAVE_RINT

#endif

#ifdef HAVE_BROKEN_SNPRINTF	/* HPUX 10.20 don't have this defined */

#undef HAVE_SNPRINTF

#endif

#define setrlimit cma_setrlimit64

#endif

#ifdef __QNXNTO__

/* This has to be after include limits.h */

#define HAVE_ERRNO_AS_DEFINE

#define HAVE_FCNTL_LOCK

#undef  HAVE_SYS_UN_H

#undef  HAVE_FINITE

#undef  HAVE_RINT

#undef  LONGLONG_MIN            /* These get wrongly defined in QNX 6.2 */

#undef  LONGLONG_MAX            /* standard system library 'limits.h' */

#endif

/* We can not live without the following defines */

#define USE_MYFUNC 1		/* Must use syscall indirection */

#define HAVE_LONG_LONG 1

#endif

#ifdef __QNXNTO__

#undef  LONGLONG_MIN            /* These get wrongly defined in QNX 6.2 */

#undef  LONGLONG_MAX            /* standard system library 'limits.h' */

#endif

#if defined(HAVE_LONG_LONG) && !defined(LONGLONG_MIN)

#define LONGLONG_MIN	((long long) 0x8000000000000000LL)

#define LONGLONG_MAX	((long long) 0x7FFFFFFFFFFFFFFFLL)

#if defined(HPUX) && !defined(DONT_REMAP_PTHREAD_FUNCTIONS)

#undef pthread_cond_timedwait

#undef pthread_mutex_trylock

#define pthread_cond_timedwait(a,b,c) my_pthread_cond_timedwait((a),(b),(c))

#define pthread_mutex_trylock(a) my_pthread_mutex_trylock((a))

int my_pthread_cond_timedwait(pthread_cond_t *cond, pthread_mutex_t *mutex,

#ifdef HAVE_SEMAPHORE_H

#include <semaphore.h>

#elif defined(__bsdi__)

#include <sys/errno.h>

#else

#ifdef __WIN__

typedef HANDLE sem_t;

#else

  pthread_cond_t  cond;

  uint            count;

} sem_t;

#endif

#endif /* __WIN__ */

int sem_init(sem_t * sem, int pshared, unsigned int value);

int sem_destroy(sem_t * sem);

int sem_post_multiple(sem_t * sem, unsigned int count);

int sem_getvalue(sem_t * sem, unsigned int * sval);

#endif

#endif /* !__bsdi__ */

C_MODE_END

#endif /* !_my_semaphore_h_ */