Merge work:/home/bk/mysql into donna.mysql.com:/home/my/bk/mysql

bk@work.mysql.com

davida@work.mysql.com

jamppa@work.mysql.com

jcole@ham.spaceapes.com

jcole@jcole.burghcom.com

jcole@nslinux.bedford.progress.com

jcole@tetra.bedford.progress.com

jcole@tetra.spaceapes.com

matt@work.mysql.com

monty@tramp.mysql.fi

monty@donna.mysql.com

monty@work.mysql.com

mwagner@evoq.home.mwagner.org

nusphere@main.burghcom.com

paul@central.snake.net

paul@work.mysql.com

sasha@mysql.sashanet.com

sasha@work.mysql.com

serg@infomag.ape.relarn.ru

serg@work.mysql.com

sinisa@work.mysql.com

spurr@nslinux.bedford.progress.com

tim@localhost.polyesthetic.msg

tim@threads.polyesthetic.msg

tim@work.mysql.com

tonu@work.mysql.com

* Command-line options::        Command-line options

* Option files::                Option files

Is there anything special to do when upgrading/downgrading MySQL?

Is There Anything Special to Do when Upgrading/Downgrading MySQL?

* Upgrading-from-3.22::         Upgrading from a 3.22 version to 3.23

* Upgrading-from-3.21::         Upgrading from a 3.21 version to 3.22

* Upgrading-from-3.20::         Upgrading from a 3.20 version to 3.21

* Upgrading-to-arch::           Upgrading to another architecture

How standards-compatible is MySQL?

How Standards-compatible Is MySQL?

* Extensions to ANSI::          @strong{MySQL} extensions to ANSI SQL92

* Ansi mode::                   Running @strong{MySQL} in ANSI mode

* Standards::                   What standards does @strong{MySQL} follow?

* Commit-rollback::             How to cope without @code{COMMIT}-@code{ROLLBACK}

Functionality missing from MySQL

Functionality Missing from MySQL

* Missing Sub-selects::         Sub-selects

* Missing SELECT INTO TABLE::   @code{SELECT INTO TABLE}

* Broken Foreign KEY::          Reasons NOT to use foreign keys

The MySQL access privilege system

The MySQL Access Privilege System

* General security::            General security

* Security::                    How to make @strong{MySQL} secure against crackers

* Passwords::                   How to set up passwords

* Access denied::               Causes of @code{Access denied} errors

MySQL language reference

MySQL Language Reference

* Literals::                    Literals: how to write strings and numbers

* Variables::                   User variables

* CREATE FUNCTION::             @code{CREATE FUNCTION} syntax

* Reserved words::              Is @strong{MySQL} picky about reserved words?

Literals: how to write strings and numbers

Literals: How to Write Strings and Numbers

* String syntax::               Strings

* Number syntax::               Numbers

* NULL values::                 @code{NULL} values

* Legal names::                 Database, table, index, column and alias names

Database, table, index, column and alias names

Database, Table, Index, Column, and Alias Names

* Name case sensitivity::       Case sensitivity in names

Column types

Column Types

* Storage requirements::        Column type storage requirements

* Numeric types::               Numeric types

* Multiple-column indexes::     Multiple-column indexes

* Other-vendor column types::   Using column types from other database engines

Date and time types

Date and Time Types

* Y2K issues::                  Y2K issues and date types

* DATETIME::                    The @code{DATETIME}, @code{DATE} and @code{TIMESTAMP} types

* TIME::                        The @code{TIME} type

* YEAR::                        The @code{YEAR} type

String types

String Types

* CHAR::                        The @code{CHAR} and @code{VARCHAR} types

* BLOB::                        The @code{BLOB} and @code{TEXT} types

* ENUM::                        The @code{ENUM} type

* SET::                         The @code{SET} type

Functions for use in @code{SELECT} and @code{WHERE} clauses

Functions for Use in @code{SELECT} and @code{WHERE} Clauses

* Grouping functions::          Grouping functions

* Arithmetic functions::        Normal arithmetic operations

* Miscellaneous functions::     Miscellaneous functions

* Group by functions::          Functions for @code{GROUP BY} clause

@code{CREATE TABLE} syntax

@code{CREATE TABLE} Syntax

* Silent column changes::       Silent column changes

* Estimating performance::      Estimating query performance

* SELECT speed::                Speed of @code{SELECT} queries

* Where optimizations::         How MySQL optimizes @code{WHERE} clauses

* DISTINCT optimization::       

* LEFT JOIN optimization::      How MySQL optimizes @code{LEFT JOIN}

* LIMIT optimization::          How MySQL optimizes @code{LIMIT}

* Insert speed::                Speed of @code{INSERT} queries

fatal bugs and make small, relatively safe changes to that version.

@end itemize

The second decision to make is whether you want to use a source distribution or

a binary distribution:

The second decision to make is whether you want to use a source

distribution or a binary distribution.  In most cases you should probably

use a binary distribution, if there exist one for your platform, as this

is generally, it will be easier to install than a source distribution.

In the following cases you will probably be better of with a source

installation:

@itemize @bullet

@item

If you want to install @strong{MySQL} at some explicit location. (The standard

binary distributions are 'ready to run' at any place, but you may want

to get even more flexibility).

@item

If you want to configure @code{mysqld} with some extra feature that is NOT in

the standard binary distributions. Here follows a list of the most common

extra options that you may want to use

@itemize @bullet

@item --with-berkeley-db

@item --with-raid

@item --with-libwrap

@item --with-named-z-lib  (This is done for some of the binaries)

@item --with-debugging[=full]

@end itemize

@item

The default binary distribution is normally compiled with support

for all characters sets and should work on a variety of processors from

the same processor family.

If you want a faster @strong{MySQL} server you may want to recompile it

with support for only the character sets you need, use a better compiler

(like pgcc) or use compiler options that are better optimized for your

processor.

@item

If you want to run @strong{MySQL} on a platform for which a current binary

distribution exists, use that.  Generally, it will be easier to install

than a source distribution.

If you have found a bug and reported it to the @strong{MySQL}

development team you will probably got a patch that you need to apply to

the source distribution to get the bug fixed.

@item

If you want to read (and/or modify) the C and C++ code that makes up

@item @strong{Filename} @tab @strong{Purpose}

@item @code{/etc/my.cnf} @tab Global options

@item @code{DATADIR/my.cnf} @tab Server-specific options

@item @code{defaults-extra-file} @tab The file specified with --defaults-extra-file=#

@item @code{~/.my.cnf} @tab User-specific options

@end multitable

large systems.  You can copy @file{my-xxxx.cnf} to your home directory

(rename the copy to @file{.my.cnf}) to experiment with this.

To tell a @strong{MySQL} program not to read any option files, specify

@code{--no-defaults} as the first option on the command line.  This

@strong{MUST} be the first option or it will have no effect!

If you want to check which options are used, you can give the option

@code{--print-defaults} as the first option.

All @strong{MySQL} clients that support option files support the

following options:

If you want to force the use of a specific config file, you can use the option

@code{--defaults-file=full-path-to-default-file}. If you do this, only the

specified file will be read.

@multitable @columnfractions .40 .60

@item --no-defaults @tab Don't read any option files.

@item --print-defaults @tab Print the program name and all options that it will get.

@item --defaults-file=full-path-to-default-file @tab Only use the given configuration file.

@item --defaults-extra-file=full-path-to-default-file @tab Read this configuration file after the global configuration file but before the user configuration file.

@end multitable

Note that the above options must be first on the command line to work!

@code{--print-defaults} may however be used directly after the

@code{--defaults-xxx-file} commands.

Note for developers:  Option file handling is implemented simply by

processing all matching options (that is, options in the appropriate group)

Check the source code of any of the standard @strong{MySQL} clients to see

how to do this.

In shell scripts you can use the @file{my_print_defaults} command to parse the

config files:

@example

shell> my_print_defaults client mysql

--port=3306

--socket=/tmp/mysql.sock

--no-auto-rehash

@end example

The above output contains all options for the groups 'client' and 'mysql'.

@node Upgrade,  , Post-installation, Installing

@section Is There Anything Special to Do when Upgrading/Downgrading MySQL?

@cindex upgrading

strings that can be found in this column:

@table @code

@item Distinct

@strong{MySQL} will not continue searching for more rows for the current row

combination after it has found the first matching row.

@item Not exists

@strong{MySQL} was able to do a @code{LEFT JOIN} optimization on the

query and will not examine more rows in this table for a row combination

@code{GRANT} are:

@itemize @bullet

@item

In @strong{MySQL} privileges are given for an username + hostname combination

and not only for an username.

@item

ANSI SQL doesn't have global or database-level privileges and ANSI SQL

doesn't support all privilege types that @strong{MySQL} supports.

@strong{MySQL} doesn't support the ANSI SQL @code{TRIGGER}, @code{EXECUTE} or

@code{UNDER} privileges.

@item

ANSI SQL privileges are structured in a hierarchal manner. If you remove

an user, all privileges the user has granted are revoked. In

@strong{MySQL} the granted privileges are not automaticly revoked, but

you have to revoke these yourself if needed.

@item

If you in @code{MySQL} have the @code{INSERT} grant on only part of the

columns in a table, you can execute @code{INSERT} statements on the

table; The columns for which you don't have the @code{INSERT} privilege

will set to their default values. ANSI SQL requires you to have the

@code{INSERT} privilege on all columns.

@item

When you drop a table in ANSI SQL, all privileges for the table are revoked.

* Estimating performance::      Estimating query performance

* SELECT speed::                Speed of @code{SELECT} queries

* Where optimizations::         How MySQL optimizes @code{WHERE} clauses

* DISTINCT optimization::       

* LEFT JOIN optimization::      How MySQL optimizes @code{LEFT JOIN}

* LIMIT optimization::          How MySQL optimizes @code{LIMIT}

* Insert speed::                Speed of @code{INSERT} queries

@cindex optimizations

@findex WHERE

@node Where optimizations, LEFT JOIN optimization, SELECT speed, Query Speed

@node Where optimizations, DISTINCT optimization, SELECT speed, Query Speed

@subsection How MySQL optimizes @code{WHERE} clauses

The @code{WHERE} optimizations are put in the @code{SELECT} part here because

BY} come from the same table, then this table is preferred first when

joining.

@item

If there is an @code{ORDER BY} clause and a different @code{GROUP BY} clause,

or if the @code{ORDER BY} or @code{GROUP BY}

contains columns from tables other than the first table in the join

queue, a temporary table is created.

If there is an @code{ORDER BY} clause and a different @code{GROUP BY}

clause, or if the @code{ORDER BY} or @code{GROUP BY} contains columns

from tables other than the first table in the join queue, a temporary

table is created.

@item

If you use @code{SQL_SMALL_RESULT}, @strong{MySQL} will use an in-memory

temporary table.

@item

As @code{DISTINCT} is converted to a @code{GROUP BY} on all columns,

@code{DISTINCT} combined with @code{ORDER BY} will in many cases also need

a temporary table.

@item

Each table index is queried and the best index that spans fewer than 30% of

the rows is used. If no such index can be found, a quick table scan is used.

@item

mysql> SELECT ... FROM tbl_name ORDER BY key_part1 DESC,key_part2 DESC,...

@end example

@findex DISTINCT

@cindex optimizing, DISTINCT

@node DISTINCT optimization, LEFT JOIN optimization, Where optimizations, Query Speed

@subsection How MySQL optimizes @code{DISTINCT}

@code{DISTINCT} is converted to a @code{GROUP BY} on all columns,

@code{DISTINCT} combined with @code{ORDER BY} will in many cases also

need a temporary table.

When combining @code{LIMIT #} with @code{DISTINCT}, @strong{MySQL} will stop

as soon as it finds @code{#} unique rows.

If you don't use columns from all used tables, @strong{MySQL} will stop

the scanning of the not used tables as soon as it has found the first match.

@example

SELECT DISTINCT t1.a FROM t1,t2 where t1.a=t2.a;

@end example

In the case, assuming t1 is used before t2 (check with @code{EXPLAIN}), then

@strong{MySQL} will stop reading from t2 (for that particular row in t1)

when the first row in t2 is found.

@findex LEFT JOIN

@cindex optimizing, LEFT JOIN

@node LEFT JOIN optimization, LIMIT optimization, Where optimizations, Query Speed

@node LEFT JOIN optimization, LIMIT optimization, DISTINCT optimization, Query Speed

@subsection How MySQL optimizes @code{LEFT JOIN} and @code{RIGHT JOIN}

@code{A LEFT JOIN B} is in @strong{MySQL} implemented as follows:

flush-privileges} or with the SQL command @code{FLUSH PRIVILEGES}.

@end enumerate

Note that after you started @code{mysqld} with @code{--skip-grant-tables},

any usage of @code{GRANT} commands will give you an @code{Unknown command}

error until you have executed @code{FLUSH PRIVILEGES}.

@cindex files, permissions

@cindex error mesaages, can't find file

@cindex files, not found message

@appendixsubsec Changes in release 3.23.26

@itemize @bullet

@item

Added optimization of queries where @code{DISTINCT} is only used on columns

from some of the tables.

@item

Allow floating point numbers where there are no sign after the exponent

(like 1e1).

@item

@code{SHOW GRANTS} didn't always show all column grants.

@item

Added @code{--default-extra-file=#} to all @strong{MySQL} clients.

@item

Automatic repair of @code{MyISAM} tables.

@item

Columns referenced in @code{INSERT} are are now properly initialized.

{

  {"config-file",	required_argument, 0,	'c'},

  {"defaults-file",	required_argument, 0,	'c'},

  {"defaults-extra-file", required_argument, 0,	'e'},

  {"extra-file", 	required_argument, 0,	'e'},

  {"no-defaults",	no_argument,	   0,	'd'},

  {"help",		no_argument,	   0,	'?'},

  {"version",		no_argument,	   0,	'V'},

static void usage(my_bool version)

{

  printf("%s  Ver 1.1 for %s at %s\n",my_progname,SYSTEM_TYPE,

  printf("%s  Ver 1.2 for %s at %s\n",my_progname,SYSTEM_TYPE,

	 MACHINE_TYPE);

  if (version)

    return;

  printf("\n\

  -c, --config-file=#, --defaults-file=#\n\

	                The config file to use (default '%s')\n\

  -e, --extra-file=#, --defaults-extra-file=#\n\

			Read this file after the global /etc config file and\n\

			before the config file in the users home directory.\n\

  --no-defaults		Return an empty string (useful for scripts)\n\

  -?, --help		Display this help message and exit.\n\

  -V, --version		Output version information and exit.\n",

{

  int c,option_index;

  while ((c=getopt_long(*argc,*argv,"c:V?I",

  while ((c=getopt_long(*argc,*argv,"c:e:V?I",

			long_options, &option_index)) != EOF)

  {

    switch (c) {

    case 'c':

      config_file=optarg;

      break;

    case 'e':

      defaults_extra_file=optarg;		/* Used by the load_defaults */

      break;

    case 'n':

      exit(0);

    case 'I':

       NEAR my_disable_flush_key_blocks;

extern char	wild_many,wild_one,wild_prefix;

extern const char *charsets_dir;

extern char *defaults_extra_file;

typedef struct wild_file_pack	/* Struct to hold info when selecting files */

{

** The following arguments are handled automaticly;  If used, they must be

** first argument on the command line!

** --no-defaults	; no options are read.

** --print-defaults	; Print the modified command line and exit

** --defaults-file=full-path-to-default-file	; Only this file will be read.

** --defaults-extra-file=full-path-to-default-file ; Read this file before ~/

** --print-defaults	; Print the modified command line and exit

****************************************************************************/

#undef SAFEMALLOC		/* safe_malloc is not yet initailized */

#include "m_string.h"

#include "m_ctype.h"

char *defaults_extra_file=0;

/* Which directories are searched for options (and in which order) */

const char *default_directories[]= {

#ifdef DATADIR

DATADIR,

#endif

"",					/* Place for defaults_extra_dir */

#ifndef __WIN__

"~/",

#endif

		   int *argc, char ***argv)

{

  DYNAMIC_ARRAY args;

  const char **dirs, *extra_default_file;

  const char **dirs, *forced_default_file;

  TYPELIB group;

  my_bool found_print_defaults=0;

  uint args_used=0;

  MEM_ROOT alloc;

  char *ptr,**res;

  DBUG_ENTER("load_defaults");

  }

  /* Check if we want to force the use a specific default file */

  extra_default_file=0;

  if (*argc >= 2 && is_prefix(argv[0][1],"--defaults-file="))

    extra_default_file=strchr(argv[0][1],'=')+1;

  forced_default_file=0;

  if (*argc >= 2)

  {

    if (is_prefix(argv[0][1],"--defaults-file="))

    {

      forced_default_file=strchr(argv[0][1],'=')+1;

      args_used++;

    }

    else if (is_prefix(argv[0][1],"--defaults-extra-file="))

    {

      defaults_extra_file=strchr(argv[0][1],'=')+1;

      args_used++;

    }

  }

  group.count=0;

  group.name= "defaults";

  if (init_dynamic_array(&args, sizeof(char*),*argc, 32))

    goto err;

  if (extra_default_file)

  if (forced_default_file)

  {

    if (search_default_file(&args, &alloc, "", extra_default_file, "",

    if (search_default_file(&args, &alloc, "", forced_default_file, "",

			    &group))

      goto err;

  }

#endif

    for (dirs=default_directories ; *dirs; dirs++)

    {

      if (search_default_file(&args, &alloc, *dirs, conf_file, default_ext,

			      &group))

      int error;

      if (**dirs)

	error=search_default_file(&args, &alloc, *dirs, conf_file,

				  default_ext, &group);

      else if (defaults_extra_file)

	error=search_default_file(&args, &alloc, NullS, defaults_extra_file,

				  default_ext, &group);

      if (error)

	goto err;

    }

  }

  /* copy name + found arguments + command line arguments to new array */

  res[0]=argv[0][0];

  memcpy((gptr) (res+1), args.buffer, args.elements*sizeof(char*));

  if (extra_default_file)

  {

    --*argc;					/* Skipp --defaults-file */

    ++*argv;

  }

  /* Skipp --defaults-file and --defaults-extra-file */

  (*argc)-= args_used;

  (*argv)+= args_used;

  /* Check if we wan't to see the new argument list */

  if (*argc >= 2 && !strcmp(argv[0][1],"--print-defaults"))