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

@sp 10

@center @titlefont{@strong{MySQL} Reference Manual}

@sp 10

@center Copyright @copyright{} 1997-2001 TcX AB, Detron HB and MySQL Finland AB

@center Copyright @copyright{} 1997-2001 MySQL AB

@c blank page after title page makes page 1 be a page front.

@c also makes the back of the title page blank.

@page

between @strong{MySQL} and BDB tables, so it will take some time before this

is as tested as the other table types.

@item Innodb Tables -- Alpha

@item InnoDB Tables -- Alpha

This is a very recent addition to @code{MySQL} and is not very tested yet.

@item Automatic recovery of MyISAM tables - Beta

If you are using Gemini tables, refer to the Gemini-specific startup options.

@xref{GEMINI start}.

If you are using Innodb tables, refer to the Innodb-specific startup

If you are using InnoDB tables, refer to the InnoDB-specific startup

options.  @xref{InnoDB start}.

@node Automatic start, Command-line options, Starting server, Post-installation

somewhat limit @code{LOAD DATA INFILE} and @code{SELECT ... INTO OUTFILE} 

though.

@item --core-file

Write a core file if @code{mysqld} dies.  For some systems you must also

specify @code{--core-file-size} to @code{safe_mysqld}. @xref{safe_mysqld}.

@item -h, --datadir=path

Path to the database root.

server to start using the grant tables again by executing @code{mysqladmin

flush-privileges} or @code{mysqladmin reload}.)

@item --skip-host-cache

Never use host name cache for faster name-ip resolution, but query DNS server

on every connect instead.  @xref{DNS}.

@item --skip-locking

Don't use system locking.  To use @code{isamchk} or @code{myisamchk} you must

shut down the server.  @xref{Stability}.  Note that in @strong{MySQL} Version

@code{mysqld} must be made via Unix sockets.  This option is highly 

recommended for systems where only local requests are allowed.  @xref{DNS}.

@item --skip-host-cache

Never use host name cache for faster name-ip resolution, but query DNS server

on every connect instead.  @xref{DNS}.

@item --skip-new

Don't use new, possible wrong routines.  Implies @code{--skip-delay-key-write}.

This will also set default table type to @code{ISAM}.  @xref{ISAM}.

@item --skip-stack-trace

Don't write stack traces.  This option is useful when you are running

@code{mysqld} under a debugger. @xref{Debugging server}.

@item --skip-safemalloc

If @strong{MySQL} is configured with @code{--with-debug=full}, all programs

will check the memory for overruns for every memory allocation and memory

@xref{mysql_insert_id, , @code{mysql_insert_id()}}.

If you delete the row containing the maximum value for an

@code{AUTO_INCREMENT} column, the value will be reused with an ISAM

table but not with a @code{MyISAM} table.  If you delete all rows in the

table with @code{DELETE FROM table_name} (without a @code{WHERE}) in

@code{AUTO_INCREMENT} column, the value will be reused with an

@code{ISAM}, @code{BDB} or @code{INNODB} table but not with a

@code{MyISAM} table.  If you delete all rows in the table with

@code{DELETE FROM table_name} (without a @code{WHERE}) in

@code{AUTOCOMMIT} mode, the sequence starts over for both table types.

@strong{NOTE:} There can be only one @code{AUTO_INCREMENT} column per

@code{YES} if @code{mysqld} supports Gemini tables. @code{DISABLED}

if @code{--skip-gemini} is used.

@item @code{have_innodb}

@code{YES} if @code{mysqld} supports Innodb tables. @code{DISABLED}

@code{YES} if @code{mysqld} supports InnoDB tables. @code{DISABLED}

if @code{--skip-innodb} is used.

@item @code{have_raid}

@code{YES} if @code{mysqld} supports the @code{RAID} option.

The default table type in @strong{MySQL} is @code{MyISAM}. If you are

trying to use a table type that is not compiled-in or activated,

@strong{MySQL} will instead create a table of type @code{MyISAM}.

@strong{MySQL} will instead create a table of type @code{MyISAM}.  This

is a very useful feature when you want to copy tables between different

SQL servers that supports different table types (like copying tables to

a slave that is optimized for speed by not having transactional tables).

This automatic table changing can however also be very confusing for new

@strong{MySQL} users. We plan to fix this by introducing warnings in

@strong{MySQL} 4.0 and giving a warning when a table type is automaticly

changed.

You can convert tables between different types with the @code{ALTER

TABLE} statement. @xref{ALTER TABLE, , @code{ALTER TABLE}}.

will automatically update this on @code{INSERT/UPDATE}. The

@code{AUTO_INCREMENT} value can be reset with @code{myisamchk}. This

will make @code{AUTO_INCREMENT} columns faster (at least 10 %) and old

numbers will not be reused as with the old ISAM. Note that when an

numbers will not be reused as with the old @code{ISAM}. Note that when an

@code{AUTO_INCREMENT} is defined on the end of a multi-part-key the old

behavior is still present.

@item

@section BDB or Berkeley_DB Tables

@menu

* BDB overview::                

* BDB install::                 

* BDB start::                   

* BDB characteristic::          

* BDB TODO::                    

* BDB portability::             

* BDB errors::                  

* BDB overview::                Overview of BDB Tables

* BDB install::                 Installing BDB

* BDB start::                   BDB startup options

* BDB characteristic::          Some characteristic of @code{BDB} tables:

* BDB TODO::                    Some things we need to fix for BDB in the near future:

* BDB portability::             Operating systems supported by @strong{BDB}

* BDB errors::                  Errors You May Get When Using BDB Tables

@end menu

@node BDB overview, BDB install, BDB, BDB

@subsection Overview of BDB Tables

Support for BDB tables is included in the @strong{MySQL} source distribution

starting from Version 3.23.34 and will be activated in the @strong{MySQL}-Max

starting from Version 3.23.34 and is activated in the @strong{MySQL}-Max

binary.

BerkeleyDB, available at @uref{http://www.sleepycat.com/} has provided 

@subsection Some restrictions on InnoDB tables

@itemize @bullet

@item You cannot create an index on a prefix of a column:

@item

If you try to create an unique index on a prefix of a column you will get an

error:

@example

@code{CREATE TABLE T (A CHAR(20), B INT, INDEX T_IND (A(5))) TYPE = InnoDB;

}

CREATE TABLE T (A CHAR(20), B INT, UNIQUE (A(5))) TYPE = InnoDB;

@end example

The above will not work. For a MyISAM table the above would create an index

where only the first 5 characters from column @code{A} are stored.

If you create a non unique index on a prefix of a column, InnoDB will

create an index over the whole column.

@item

@code{INSERT DELAYED} is not supported for InnoDB tables.

@item

@cindex @code{safe-mode} command

A useful startup option for beginners (introduced in @strong{MySQL}

Version 3.23.11) is @code{--safe-mode} (or @code{--i-am-a-dummy} for

Version 3.23.11) is @code{--safe-updates} (or @code{--i-am-a-dummy} for

users that has at some time done a @code{DELETE FROM table_name} but

forgot the @code{WHERE} clause.  When using this option, @code{mysql}

forgot the @code{WHERE} clause).  When using this option, @code{mysql}

sends the following command to the @strong{MySQL} server when opening

the connection:

For mysqld to be able to use UDF functions, you should configure MySQL

with @code{--with-mysqld-ldflags=-rdynamic} The reason is that to on

many platforms you can load a dynamic library (with @code{dlopen()})

from a static linked program, which you would get if you are using

@code{--with-mysqld-ldflags=-all-static} If you want to use an UDF that

needs to access symbols from mysqld (like the @code{methaphone} example

in @file{sql/udf_example.cc} that uses @code{default_charset_info}), you must

link the program with @code{-rdynamic}.  (see @code{man dlopen}).

many platforms (including Linux) you can load a dynamic library (with

@code{dlopen()}) from a static linked program, which you would get if

you are using @code{--with-mysqld-ldflags=-all-static} If you want to

use an UDF that needs to access symbols from mysqld (like the

@code{methaphone} example in @file{sql/udf_example.cc} that uses

@code{default_charset_info}), you must link the program with

@code{-rdynamic}.  (see @code{man dlopen}).

For each function that you want to use in SQL statements, you should define

corresponding C (or C++) functions.  In the discussion below, the name

@node Adding native function,  , Adding UDF, Adding functions

@section Adding a New Native Function

The procedure for adding a new native function is described below.  Note that

you cannot add native functions to a binary distribution because the procedure

involves modifying @strong{MySQL} source code.  You must compile

@strong{MySQL} yourself from a source distribution.  Also note that if you

migrate to another version of @strong{MySQL} (for example, when a new version is

released), you will need to repeat the procedure with the new version.

The procedure for adding a new native function is described below.  Note

that you cannot add native functions to a binary distribution because

the procedure involves modifying @strong{MySQL} source code.  You must

compile @strong{MySQL} yourself from a source distribution.  Also note

that if you migrate to another version of @strong{MySQL} (for example,

when a new version is released), you will need to repeat the procedure

with the new version.

To add a new native @strong{MySQL} function, follow these steps:

@item @strong{BerkeleyDB} or @strong{BDB}

Uses the Berkeley DB library from Sleepycat Software to implement 

transaction-safe tables.  

@item @strong{Innodb}

@item @strong{InnoDB}

A transaction-safe table handler that supports row level locking, and many

Oracle-like features.

@c change "three" to "four" above when uncommenting this

@appendixsubsec Changes in release 3.23.38

@itemize @bullet

@item

Fixed a bug in @code{REPLACE()} when using the ujis character set.

@item

Applied Sleepycat BDB patches 3.2.9.1 and 3.2.9.2.

@item

Added option @code{--skip-stack-trace} to @code{mysqld}.

@item

@code{CREATE TEMPORARY} now works with @code{InnoDB} tables.

@item

@code{InnoDB} now promotes sub keys to whole keys.

@item

Added option @code{CONCURRENT} to @code{LOAD DATA}.

@item

Better error message when slave @code{max_allowed_packet} is to low to

Subqueries.

@code{select id from t where grp in (select grp from g where u > 100)}

@item

Derieved tables.

@example

select a.col1, b.col2 from (select max(col1) as col1 from root_table ) a,

other_table b where a.col1=b.col1

@end example

This could be done by automaticly create temporary tables for the

derived tables for the duration of the query.

@item

Add @code{PREPARE} of statements and sending of parameters to @code{mysqld}.

@item

Extend the server/client protocol to support warnings.

@item

Add options to the server/protocol protocol to get progress notes

for long running commands.

@item

Add database and real table name (in case of alias) to the MYSQL_FIELD

structure.

@item

Don't allow more than a defined number of threads to run MyISAM recover

at the same time.

@item

Change the protocol to allow binary transfer of values. To do this

efficiently, we need to add an API to allow binding of variables.

@item

Add @code{PREPARE} of statements and sending of parameters to @code{mysqld}.

@item

Make it possible to specify @code{long_query_time} with a granularity

in microseconds.

@item

--one-thread} if you want to be able to debug @code{mysqld} threads.  In

this case you can only have one thread active at a time.

When running @code{mysqld} under gdb, you should disable the stack trace

with @code{--skip-stack-trace} to be able to catch segfaults within gdb.

It's very hard to debug @strong{MySQL} under @code{gdb} if you do a lot of

new connections the whole time as @code{gdb} doesn't free the memory for

old threads.  You can avoid this problem by starting @code{mysqld} with

 */

typedef enum {

	DB_LV_INCOMPLETE,

	DB_LV_NONEXISTENT,

	DB_LV_NORMAL,

	DB_LV_OLD_READABLE,

	DB_LV_OLD_UNREADABLE

	int find_first, *valp;

	logfile_validity *statusp;

{

	logfile_validity clv_status, status;

	logfile_validity logval_status, status;

	u_int32_t clv, logval;

	int cnt, fcnt, ret;

	const char *dir;

	char **names, *p, *q, savech;

	clv_status = status = DB_LV_NORMAL;

	logval_status = status = DB_LV_NONEXISTENT;

	/* Return a value of 0 as the log file number on failure. */

	*valp = 0;

			 * as a valid log file.

			 */

			break;

		case DB_LV_NONEXISTENT:

			/* Should never happen. */

			DB_ASSERT(0);

			break;

		case DB_LV_NORMAL:

		case DB_LV_OLD_READABLE:

			logval = clv;

			clv_status = status;

			logval_status = status;

			break;

		case DB_LV_OLD_UNREADABLE:

			/*

			 */

			if (!find_first) {

				logval = clv;

				clv_status = status;

				logval_status = status;

			}

			break;

		}

err:	__os_dirfree(names, fcnt);

	__os_freestr(p);

	*statusp = clv_status;

	*statusp = logval_status;

	return (ret);

}

				TAILQ_INIT(&logp->dbentry[i].dblist);

			else

				TAILQ_REINSERT_HEAD(

				    &logp->dbentry[i].dblist, dbp, links);

				    &logp->dbentry[i].dblist, dbtmp, links);

		}

		/* Initialize the new entries. */

    }

    case ADMIN_DROP:

    {

      char buff[FN_REFLEN+20];

      if (argc < 2)

      {

	my_printf_error(0,"Too few arguments to drop",MYF(ME_BELL));