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DBD::mysql(3pm)       User Contributed Perl Documentation      DBD::mysql(3pm)



NAME
       DBD::mysql - MySQL driver for the Perl5 Database Interface (DBI)

SYNOPSIS
           use DBI;

           $dsn = "DBI:mysql:database=$database;host=$hostname;port=$port";

           $dbh = DBI->connect($dsn, $user, $password);


           $drh = DBI->install_driver("mysql");
           @databases = DBI->data_sources("mysql");
              or
           @databases = DBI->data_sources("mysql",
             {"host" => $host, "port" => $port, "user" => $user, password => $pass});

           $sth = $dbh->prepare("SELECT * FROM foo WHERE bla");
              or
           $sth = $dbh->prepare("LISTFIELDS $table");
              or
           $sth = $dbh->prepare("LISTINDEX $table $index");
           $sth->execute;
           $numRows = $sth->rows;
           $numFields = $sth->{'NUM_OF_FIELDS'};
           $sth->finish;

           $rc = $drh->func('createdb', $database, $host, $user, $password, 'admin');
           $rc = $drh->func('dropdb', $database, $host, $user, $password, 'admin');
           $rc = $drh->func('shutdown', $host, $user, $password, 'admin');
           $rc = $drh->func('reload', $host, $user, $password, 'admin');

           $rc = $dbh->func('createdb', $database, 'admin');
           $rc = $dbh->func('dropdb', $database, 'admin');
           $rc = $dbh->func('shutdown', 'admin');
           $rc = $dbh->func('reload', 'admin');

EXAMPLE
         #!/usr/bin/perl

         use strict;
         use DBI();

         # Connect to the database.
         my $dbh = DBI->connect("DBI:mysql:database=test;host=localhost",
                                "joe", "joe's password",
                                {'RaiseError' => 1});

         # Drop table 'foo'. This may fail, if 'foo' doesn't exist.
         # Thus we put an eval around it.
         eval { $dbh->do("DROP TABLE foo") };
         print "Dropping foo failed: $@\n" if $@;

         # Create a new table 'foo'. This must not fail, thus we don't
         # catch errors.
         $dbh->do("CREATE TABLE foo (id INTEGER, name VARCHAR(20))");

         # INSERT some data into 'foo'. We are using $dbh->quote() for
         # quoting the name.
         $dbh->do("INSERT INTO foo VALUES (1, " . $dbh->quote("Tim") . ")");

         # Same thing, but using placeholders
         $dbh->do("INSERT INTO foo VALUES (?, ?)", undef, 2, "Jochen");

         # Now retrieve data from the table.
         my $sth = $dbh->prepare("SELECT * FROM foo");
         $sth->execute();
         while (my $ref = $sth->fetchrow_hashref()) {
           print "Found a row: id = $ref->{'id'}, name = $ref->{'name'}\n";
         }
         $sth->finish();

         # Disconnect from the database.
         $dbh->disconnect();

DESCRIPTION
       DBD::mysql is the Perl5 Database Interface driver for the MySQL
       database. In other words: DBD::mysql is an interface between the Perl
       programming language and the MySQL programming API that comes with the
       MySQL relational database management system. Most functions provided by
       this programming API are supported. Some rarely used functions are
       missing, mainly because noone ever requested them. :-)

       In what follows we first discuss the use of DBD::mysql, because this is
       what you will need the most. For installation, see the sections on
       INSTALLATION, and "WIN32 INSTALLATION" below. See EXAMPLE for a simple
       example above.

       From perl you activate the interface with the statement

           use DBI;

       After that you can connect to multiple MySQL database servers and send
       multiple queries to any of them via a simple object oriented interface.
       Two types of objects are available: database handles and statement
       handles. Perl returns a database handle to the connect method like so:

         $dbh = DBI->connect("DBI:mysql:database=$db;host=$host",
                             $user, $password, {RaiseError => 1});

       Once you have connected to a database, you can can execute SQL
       statements with:

         my $query = sprintf("INSERT INTO foo VALUES (%d, %s)",
                             $number, $dbh->quote("name"));
         $dbh->do($query);

       See DBI(3) for details on the quote and do methods. An alternative
       approach is

         $dbh->do("INSERT INTO foo VALUES (?, ?)", undef,
                  $number, $name);

       in which case the quote method is executed automatically. See also the
       bind_param method in DBI(3). See "DATABASE HANDLES" below for more
       details on database handles.

       If you want to retrieve results, you need to create a so-called
       statement handle with:

         $sth = $dbh->prepare("SELECT * FROM $table");
         $sth->execute();

       This statement handle can be used for multiple things. First of all you
       can retreive a row of data:

         my $row = $sth->fetchrow_hashref();

       If your table has columns ID and NAME, then $row will be hash ref with
       keys ID and NAME. See "STATEMENT HANDLES" below for more details on
       statement handles.

       But now for a more formal approach:

   Class Methods
       connect
               use DBI;

               $dsn = "DBI:mysql:$database";
               $dsn = "DBI:mysql:database=$database;host=$hostname";
               $dsn = "DBI:mysql:database=$database;host=$hostname;port=$port";

               $dbh = DBI->connect($dsn, $user, $password);

           A "database" must always be specified.

           host
           port
               The hostname, if not specified or specified as '' or
               'localhost', will default to a MySQL server running on the
               local machine using the default for the UNIX socket. To connect
               to a MySQL server on the local machine via TCP, you must
               specify the loopback IP address (127.0.0.1) as the host.

               Should the MySQL server be running on a non-standard port
               number, you may explicitly state the port number to connect to
               in the "hostname" argument, by concatenating the hostname and
               port number together separated by a colon ( ":" ) character or
               by using the  "port" argument.

               To connect to a MySQL server on localhost using TCP/IP, you
               must specify the hostname as 127.0.0.1 (with the optional
               port).

           mysql_client_found_rows
               Enables (TRUE value) or disables (FALSE value) the flag
               CLIENT_FOUND_ROWS while connecting to the MySQL server. This
               has a somewhat funny effect: Without mysql_client_found_rows,
               if you perform a query like

                 UPDATE $table SET id = 1 WHERE id = 1

               then the MySQL engine will always return 0, because no rows
               have changed.  With mysql_client_found_rows however, it will
               return the number of rows that have an id 1, as some people are
               expecting. (At least for compatibility to other engines.)

           mysql_compression
               As of MySQL 3.22.3, a new feature is supported: If your DSN
               contains the option "mysql_compression=1", then the
               communication between client and server will be compressed.

           mysql_connect_timeout
               If your DSN contains the option "mysql_connect_timeout=##", the
               connect request to the server will timeout if it has not been
               successful after the given number of seconds.

           mysql_read_default_file
           mysql_read_default_group
               These options can be used to read a config file like
               /etc/my.cnf or ~/.my.cnf. By default MySQL's C client library
               doesn't use any config files unlike the client programs (mysql,
               mysqladmin, ...) that do, but outside of the C client library.
               Thus you need to explicitly request reading a config file, as
               in

                   $dsn = "DBI:mysql:test;mysql_read_default_file=/home/joe/my.cnf";
                   $dbh = DBI->connect($dsn, $user, $password)

               The option mysql_read_default_group can be used to specify the
               default group in the config file: Usually this is the client
               group, but see the following example:

                   [client]
                   host=localhost

                   [perl]
                   host=perlhost

               (Note the order of the entries! The example won't work, if you
               reverse the [client] and [perl] sections!)

               If you read this config file, then you'll be typically
               connected to localhost. However, by using

                   $dsn = "DBI:mysql:test;mysql_read_default_group=perl;"
                       . "mysql_read_default_file=/home/joe/my.cnf";
                   $dbh = DBI->connect($dsn, $user, $password);

               you'll be connected to perlhost. Note that if you specify a
               default group and do not specify a file, then the default
               config files will all be read.  See the documentation of the C
               function mysql_options() for details.

           mysql_socket
               As of MySQL 3.21.15, it is possible to choose the Unix socket
               that is used for connecting to the server. This is done, for
               example, with

                   mysql_socket=/dev/mysql

               Usually there's no need for this option, unless you are using
               another location for the socket than that built into the
               client.

           mysql_ssl
               A true value turns on the CLIENT_SSL flag when connecting to
               the MySQL database:

                 mysql_ssl=1

               This means that your communication with the server will be
               encrypted.

               If you turn mysql_ssl on, you might also wish to use the
               following flags:

           mysql_ssl_client_key
           mysql_ssl_client_cert
           mysql_ssl_ca_file
           mysql_ssl_ca_path
           mysql_ssl_cipher
               These are used to specify the respective parameters of a call
               to mysql_ssl_set, if mysql_ssl is turned on.

           mysql_local_infile
               As of MySQL 3.23.49, the LOCAL capability for LOAD DATA may be
               disabled in the MySQL client library by default. If your DSN
               contains the option "mysql_local_infile=1", LOAD DATA LOCAL
               will be enabled.  (However, this option is *ineffective* if the
               server has also been configured to disallow LOCAL.)

           mysql_multi_statements
               As of MySQL 4.1, support for multiple statements seperated by a
               semicolon (;) may be enabled by using this option. Enabling
               this option may cause problems if server-side prepared
               statements are also enabled.

           Prepared statement support (server side prepare)
               As of 3.0002_1, server side prepare statements were on by
               default (if your server was >= 4.1.3). As of 3.0009, they were
               off by default again due to issues with the prepared statement
               API (all other mysql connectors are set this way until C API
               issues are resolved). The requirement to use prepared
               statements still remains that you have a server >= 4.1.3

               To use server side prepared statements, all you need to do is
               set the variable mysql_server_prepare in the connect:

               $dbh = DBI->connect(
                                   "DBI:mysql:database=test;host=localhost;mysql_server_prepare=1",
                                   "",
                                   "",
                                   { RaiseError => 1, AutoCommit => 1 }
                                   );

               * Note: delimiter for this param is ';'

               There are many benefits to using server side prepare
               statements, mostly if you are performing many inserts because
               of that fact that a single statement is prepared to accept
               multiple insert values.

               To make sure that the 'make test' step tests whether server
               prepare works, you just need to export the env variable
               MYSQL_SERVER_PREPARE:

               export MYSQL_SERVER_PREPARE=1

           mysql_embedded_options
               The option <mysql_embedded_options> can be used to pass
               'command-line' options to embedded server.

               Example:

               $testdsn="DBI:mysqlEmb:database=test;mysql_embedded_options=--help,--verbose";

           mysql_embedded_groups
               The option <mysql_embedded_groups> can be used to specify the
               groups in the config file(my.cnf) which will be used to get
               options for embedded server.  If not specified [server] and
               [embedded] groups will be used.

               Example:

               $testdsn="DBI:mysqlEmb:database=test;mysql_embedded_groups=embedded_server,common";

   Private MetaData Methods
       ListDBs
               my $drh = DBI->install_driver("mysql");
               @dbs = $drh->func("$hostname:$port", '_ListDBs');
               @dbs = $drh->func($hostname, $port, '_ListDBs');
               @dbs = $dbh->func('_ListDBs');

           Returns a list of all databases managed by the MySQL server running
           on $hostname, port $port. This is a legacy method.  Instead, you
           should use the portable method

               @dbs = DBI->data_sources("mysql");

   Server Administration
       admin
               $rc = $drh->func("createdb", $dbname, [host, user, password,], 'admin');
               $rc = $drh->func("dropdb", $dbname, [host, user, password,], 'admin');
               $rc = $drh->func("shutdown", [host, user, password,], 'admin');
               $rc = $drh->func("reload", [host, user, password,], 'admin');

                 or

               $rc = $dbh->func("createdb", $dbname, 'admin');
               $rc = $dbh->func("dropdb", $dbname, 'admin');
               $rc = $dbh->func("shutdown", 'admin');
               $rc = $dbh->func("reload", 'admin');

           For server administration you need a server connection. For
           obtaining this connection you have two options: Either use a driver
           handle (drh) and supply the appropriate arguments (host, defaults
           localhost, user, defaults to '' and password, defaults to ''). A
           driver handle can be obtained with

               $drh = DBI->install_driver('mysql');

           Otherwise reuse the existing connection of a database handle (dbh).

           There's only one function available for administrative purposes,
           comparable to the m(y)sqladmin programs. The command being execute
           depends on the first argument:

           createdb
               Creates the database $dbname. Equivalent to "m(y)sqladmin
               create $dbname".

           dropdb
               Drops the database $dbname. Equivalent to "m(y)sqladmin drop
               $dbname".

               It should be noted that database deletion is not prompted for
               in any way.  Nor is it undo-able from DBI.

                   Once you issue the dropDB() method, the database will be gone!

               These method should be used at your own risk.

           shutdown
               Silently shuts down the database engine. (Without prompting!)
               Equivalent to "m(y)sqladmin shutdown".

           reload
               Reloads the servers configuration files and/or tables. This can
               be particularly important if you modify access privileges or
               create new users.

DATABASE HANDLES
       The DBD::mysql driver supports the following attributes of database
       handles (read only):

         $errno = $dbh->{'mysql_errno'};
         $error = $dbh->{'mysql_error'};
         $info = $dbh->{'mysql_hostinfo'};
         $info = $dbh->{'mysql_info'};
         $insertid = $dbh->{'mysql_insertid'};
         $info = $dbh->{'mysql_protoinfo'};
         $info = $dbh->{'mysql_serverinfo'};
         $info = $dbh->{'mysql_stat'};
         $threadId = $dbh->{'mysql_thread_id'};

       These correspond to mysql_errno(), mysql_error(),
       mysql_get_host_info(), mysql_info(), mysql_insert_id(),
       mysql_get_proto_info(), mysql_get_server_info(), mysql_stat() and
       mysql_thread_id(), respectively.

        $info_hashref = $dhb->{mysql_dbd_stats}

       DBD::mysql keeps track of some statistics in the mysql_dbd_stats
       attribute.  The following stats are being maintained:

       auto_reconnects_ok
           The number of times that DBD::mysql successfully reconnected to the
           mysql server.

       auto_reconnects_failed
           The number of times that DBD::mysql tried to reconnect to mysql but
           failed.

       The DBD::mysql driver also supports the following attribute(s) of
       database handles (read/write):

        $bool_value = $dbh->{mysql_auto_reconnect};
        $dbh->{mysql_auto_reconnect} = $AutoReconnect ? 1 : 0;

       mysql_auto_reconnect
           This attribute determines whether DBD::mysql will automatically
           reconnect to mysql if the connection be lost. This feature defaults
           to off; however, if either the GATEWAY_INTERFACE or MOD_PERL
           envionment variable is set, DBD::mysql will turn
           mysql_auto_reconnect on.  Setting mysql_auto_reconnect to on is not
           advised if 'lock tables' is used because if DBD::mysql reconnect to
           mysql all table locks will be lost.  This attribute is ignored when
           AutoCommit is turned off, and when AutoCommit is turned off,
           DBD::mysql will not automatically reconnect to the server.

       mysql_use_result
           This attribute forces the driver to use mysql_use_result rather
           than mysql_store_result. The former is faster and less memory
           consuming, but tends to block other processes. (That's why
           mysql_store_result is the default.)

           It is possible to set default value of the "mysql_use_result"
           attribute for $dbh using several ways:

            - through DSN

              $dbh= DBI->connect("DBI:mysql:test;mysql_use_result=1", "root", "");

            - after creation of database handle

              $dbh->{'mysql_use_result'}=0; #disable
              $dbh->{'mysql_use_result'}=1; #enable

           It is possible to set/unset the "mysql_use_result" attribute after
           creation of statement handle. See below.

       mysql_enable_utf8
           This attribute determines whether DBD::mysql should assume strings
           stored in the database are utf8.  This feature defaults to off.

           When set, a data retrieved from a textual column type (char,
           varchar, etc) will have the UTF-8 flag turned on if necessary.
           This enables character semantics on that string.  You will also
           need to ensure that your database / table / column is configured to
           use UTF8.  See Chapter 10 of the mysql manual for details.

           Additionally, turning on this flag tells MySQL that incoming data
           should be treated as UTF-8.  This will only take effect if used as
           part of the call to connect().  If you turn the flag on after
           connecting, you will need to issue the command "SET NAMES utf8" to
           get the same effect.

           This option is experimental and may change in future versions.

STATEMENT HANDLES
       The statement handles of DBD::mysql support a number of attributes. You
       access these by using, for example,

         my $numFields = $sth->{'NUM_OF_FIELDS'};

       Note, that most attributes are valid only after a successfull execute.
       An "undef" value will returned in that case. The most important
       exception is the "mysql_use_result" attribute: This forces the driver
       to use mysql_use_result rather than mysql_store_result. The former is
       faster and less memory consuming, but tends to block other processes.
       (That's why mysql_store_result is the default.)

       To set the "mysql_use_result" attribute, use either of the following:

         my $sth = $dbh->prepare("QUERY", { "mysql_use_result" => 1});

       or

         my $sth = $dbh->prepare("QUERY");
         $sth->{"mysql_use_result"} = 1;

       Column dependent attributes, for example NAME, the column names, are
       returned as a reference to an array. The array indices are
       corresponding to the indices of the arrays returned by fetchrow and
       similar methods. For example the following code will print a header of
       table names together with all rows:

         my $sth = $dbh->prepare("SELECT * FROM $table");
         if (!$sth) {
             die "Error:" . $dbh->errstr . "\n";
         }
         if (!$sth->execute) {
             die "Error:" . $sth->errstr . "\n";
         }
         my $names = $sth->{'NAME'};
         my $numFields = $sth->{'NUM_OF_FIELDS'};
         for (my $i = 0;  $i < $numFields;  $i++) {
             printf("%s%s", $i ? "," : "", $$names[$i]);
         }
         print "\n";
         while (my $ref = $sth->fetchrow_arrayref) {
             for (my $i = 0;  $i < $numFields;  $i++) {
                 printf("%s%s", $i ? "," : "", $$ref[$i]);
             }
             print "\n";
         }

       For portable applications you should restrict yourself to attributes
       with capitalized or mixed case names. Lower case attribute names are
       private to DBD::mysql. The attribute list includes:

       ChopBlanks
           this attribute determines whether a fetchrow will chop preceding
           and trailing blanks off the column values. Chopping blanks does not
           have impact on the max_length attribute.

       mysql_insertid
           MySQL has the ability to choose unique key values automatically. If
           this happened, the new ID will be stored in this attribute. An
           alternative way for accessing this attribute is via
           $dbh->{'mysql_insertid'}.  (Note we are using the $dbh in this
           case!)

       mysql_is_blob
           Reference to an array of boolean values; TRUE indicates, that the
           respective column is a blob. This attribute is valid for MySQL
           only.

       mysql_is_key
           Reference to an array of boolean values; TRUE indicates, that the
           respective column is a key. This is valid for MySQL only.

       mysql_is_num
           Reference to an array of boolean values; TRUE indicates, that the
           respective column contains numeric values.

       mysql_is_pri_key
           Reference to an array of boolean values; TRUE indicates, that the
           respective column is a primary key.

       mysql_is_auto_increment
           Reference to an array of boolean values; TRUE indicates that the
           respective column is an AUTO_INCREMENT column.  This is only valid
           for MySQL.

       mysql_length
       mysql_max_length
           A reference to an array of maximum column sizes. The max_length is
           the maximum physically present in the result table, length gives
           the theoretically possible maximum. max_length is valid for MySQL
           only.

       NAME
           A reference to an array of column names.

       NULLABLE
           A reference to an array of boolean values; TRUE indicates that this
           column may contain NULL's.

       NUM_OF_FIELDS
           Number of fields returned by a SELECT or LISTFIELDS statement.  You
           may use this for checking whether a statement returned a result: A
           zero value indicates a non-SELECT statement like INSERT, DELETE or
           UPDATE.

       mysql_table
           A reference to an array of table names, useful in a JOIN result.

       TYPE
           A reference to an array of column types. The engine's native column
           types are mapped to portable types like DBI::SQL_INTEGER() or
           DBI::SQL_VARCHAR(), as good as possible. Not all native types have
           a meaningfull equivalent, for example
           DBD::mysql::FIELD_TYPE_INTERVAL is mapped to DBI::SQL_VARCHAR().
           If you need the native column types, use mysql_type. See below.

       mysql_type
           A reference to an array of MySQL's native column types, for example
           DBD::mysql::FIELD_TYPE_SHORT() or DBD::mysql::FIELD_TYPE_STRING().
           Use the TYPE attribute, if you want portable types like
           DBI::SQL_SMALLINT() or DBI::SQL_VARCHAR().

       mysql_type_name
           Similar to mysql, but type names and not numbers are returned.
           Whenever possible, the ANSI SQL name is preferred.

       mysql_warning_count
           The number of warnings generated during execution of the SQL
           statement.

TRANSACTION SUPPORT
       Beginning with DBD::mysql 2.0416, transactions are supported.  The
       transaction support works as follows:

       o   By default AutoCommit mode is on, following the DBI specifications.

       o   If you execute

               $dbh->{'AutoCommit'} = 0;

           or

               $dbh->{'AutoCommit'} = 1;

           then the driver will set the MySQL server variable autocommit to 0
           or 1, respectively. Switching from 0 to 1 will also issue a COMMIT,
           following the DBI specifications.

       o   The methods

               $dbh->rollback();
               $dbh->commit();

           will issue the commands COMMIT and ROLLBACK, respectively. A
           ROLLBACK will also be issued if AutoCommit mode is off and the
           database handles DESTROY method is called. Again, this is following
           the DBI specifications.

       Given the above, you should note the following:

       o   You should never change the server variable autocommit manually,
           unless you are ignoring DBI's transaction support.

       o   Switching AutoCommit mode from on to off or vice versa may fail.
           You should always check for errors, when changing AutoCommit mode.
           The suggested way of doing so is using the DBI flag RaiseError.  If
           you don't like RaiseError, you have to use code like the following:

             $dbh->{'AutoCommit'} = 0;
             if ($dbh->{'AutoCommit'}) {
               # An error occurred!
             }

       o   If you detect an error while changing the AutoCommit mode, you
           should no longer use the database handle. In other words, you
           should disconnect and reconnect again, because the transaction mode
           is unpredictable. Alternatively you may verify the transaction mode
           by checking the value of the server variable autocommit.  However,
           such behaviour isn't portable.

       o   DBD::mysql has a "reconnect" feature that handles the so-called
           MySQL "morning bug": If the server has disconnected, most probably
           due to a timeout, then by default the driver will reconnect and
           attempt to execute the same SQL statement again. However, this
           behaviour is disabled when AutoCommit is off: Otherwise the
           transaction state would be completely unpredictable after a
           reconnect.

       o   The "reconnect" feature of DBD::mysql can be toggled by using the
           mysql_auto_reconnect attribute. This behaviour should be turned off
           in code that uses LOCK TABLE because if the database server time
           out and DBD::mysql reconnect, table locks will be lost without any
           indication of such loss.

MULTIPLE RESULT SETS
       As of version 3.0002_5, DBD::mysql supports multiple result sets
       (Thanks to Guy Harrison!). This is the first release of this
       functionality, so there may be issues. Please report bugs if you run
       into them!

       The basic usage of multiple result sets is

         do
         {
           while (@row= $sth->fetchrow_array())
           {
             do stuff;
           }
         } while ($sth->more_results)

       An example would be:

         $dbh->do("drop procedure if exists someproc") or print $DBI::errstr;

         $dbh->do("create procedure somproc() deterministic
          begin
          declare a,b,c,d int;
          set a=1;
          set b=2;
          set c=3;
          set d=4;
          select a, b, c, d;
          select d, c, b, a;
          select b, a, c, d;
          select c, b, d, a;
         end") or print $DBI::errstr;

         $sth=$dbh->prepare('call someproc()') ||
         die $DBI::err.": ".$DBI::errstr;

         $sth->execute || die DBI::err.": ".$DBI::errstr; $rowset=0;
         do {
           print "\nRowset ".++$i."\n---------------------------------------\n\n";
           foreach $colno (0..$sth->{NUM_OF_FIELDS}) {
             print $sth->{NAME}->[$colno]."\t";
           }
           print "\n";
           while (@row= $sth->fetchrow_array())  {
             foreach $field (0..$#row) {
               print $row[$field]."\t";
             }
             print "\n";
           }
         } until (!$sth->more_results)

       For more examples, please see the eg/ directory. This is where helpful
       DBD::mysql code snippits will be added in the future.

   Issues with Multiple result sets
       So far, the main issue is if your result sets are "jagged", meaning,
       the number of columns of your results vary. Varying numbers of columns
       could result in your script crashing. This is something that will be
       fixed soon.

MULTITHREADING
       The multithreading capabilities of DBD::mysql depend completely on the
       underlying C libraries: The modules are working with handle data only,
       no global variables are accessed or (to the best of my knowledge)
       thread unsafe functions are called. Thus DBD::mysql is believed to be
       completely thread safe, if the C libraries are thread safe and you
       don't share handles among threads.

       The obvious question is: Are the C libraries thread safe?  In the case
       of MySQL the answer is "mostly" and, in theory, you should be able to
       get a "yes", if the C library is compiled for being thread safe (By
       default it isn't.) by passing the option -with-thread-safe-client to
       configure. See the section on How to make a threadsafe client in the
       manual.

INSTALLATION
       Windows users may skip this section and pass over to WIN32 INSTALLATION
       below. Others, go on reading.

       First of all, you do not need an installed MySQL server for installing
       DBD::mysql. However, you need at least the client libraries and
       possibly the header files, if you are compiling DBD::mysql from source.
       In the case of MySQL you can create a client-only version by using the
       configure option --without-server.  If you are using precompiled
       binaries, then it may be possible to use just selected RPM's like
       MySQL-client and MySQL-devel or something similar, depending on the
       distribution.

       First you need to install the DBI module. For using dbimon, a simple
       DBI shell it is recommended to install Data::ShowTable another Perl
       module.

       I recommend trying automatic installation via the CPAN module. Try

         perl -MCPAN -e shell

       If you are using the CPAN module for the first time, it will prompt you
       a lot of questions. If you finally receive the CPAN prompt, enter

         install Bundle::DBD::mysql

       If this fails (which may be the case for a number of reasons, for
       example because you are behind a firewall or don't have network
       access), you need to do a manual installation. First of all you need to
       fetch the modules from CPAN search

          http://search.cpan.org/

       The following modules are required

         DBI
         Data::ShowTable
         DBD::mysql

       Then enter the following commands (note - versions are just examples):

         gzip -cd DBI-(version).tar.gz | tar xf -
         cd DBI-(version)
         perl Makefile.PL
         make
         make test
         make install

         cd ..
         gzip -cd Data-ShowTable-(version).tar.gz | tar xf -
         cd Data-ShowTable-3.3
         perl Makefile.PL
         make
         make install

         cd ..
         gzip -cd DBD-mysql-(version)-tar.gz | tar xf -
         cd DBD-mysql-(version)
         perl Makefile.PL
         make
         make test
         make install

       During "perl Makefile.PL" you will be prompted some questions.  Other
       questions are the directories with header files and libraries.  For
       example, of your file mysql.h is in /usr/include/mysql/mysql.h, then
       enter the header directory /usr, likewise for
       /usr/lib/mysql/libmysqlclient.a or /usr/lib/libmysqlclient.so.

WIN32 INSTALLATION
       If you are using ActivePerl, you may use ppm to install DBD-mysql.  For
       Perl 5.6, upgrade to Build 623 or later, then it is sufficient to run

         ppm install DBI
         ppm install DBD::mysql

       If you need an HTTP proxy, you might need to set the environment
       variable http_proxy, for example like this:

         set http_proxy=http://myproxy.com:8080/

       As of this writing, DBD::mysql is missing in the ActivePerl 5.8.0
       repository. However, Randy Kobes has kindly donated an own distribution
       and the following might succeed:

         ppm install http://theoryx5.uwinnipeg.ca/ppms/DBD-mysql.ppd

       Otherwise you definitely *need* a C compiler. And it *must* be the same
       compiler that was being used for compiling Perl itself. If you don't
       have a C compiler, the file README.win32 from the Perl source
       distribution tells you where to obtain freely distributable C compilers
       like egcs or gcc. The Perl sources are available via CPAN search

         http://search.cpan.org

       I recommend using the win32clients package for installing DBD::mysql
       under Win32, available for download on www.tcx.se. The following steps
       have been required for me:

       -   The current Perl versions (5.6, as of this writing) do have a
           problem with detecting the C libraries. I recommend to apply the
           following patch:

             *** c:\Perl\lib\ExtUtils\Liblist.pm.orig Sat Apr 15 20:03:40 2000
             --- c:\Perl\lib\ExtUtils\Liblist.pm      Sat Apr 15 20:03:45 2000
             ***************
             *** 230,235 ****
             --- 230,239 ----
                 # add "$Config{installarchlib}/CORE" to default search path
                 push @libpath, "$Config{installarchlib}/CORE";

             +     if ($VC  and  exists($ENV{LIB})  and  defined($ENV{LIB})) {
             +       push(@libpath, split(/;/, $ENV{LIB}));
             +     }
             +
                 foreach (Text::ParseWords::quotewords('\s+', 0, $potential_libs)){

                   $thislib = $_;

       -   Extract sources into C:\. This will create a directory C:\mysql
           with subdirectories include and lib.

           IMPORTANT: Make sure this subdirectory is not shared by other TCX
           files! In particular do *not* store the MySQL server in the same
           directory. If the server is already installed in C:\mysql, choose a
           location like C:\tmp, extract the win32clients there.  Note that
           you can remove this directory entirely once you have installed
           DBD::mysql.

       -   Extract the DBD::mysql sources into another directory, for example
           C:\src\siteperl

       -   Open a DOS shell and change directory to C:\src\siteperl.

       -   The next step is only required if you repeat building the modules:
           Make sure that you have a clean build tree by running

             nmake realclean

           If you don't have VC++, replace nmake with your flavour of make. If
           error messages are reported in this step, you may safely ignore
           them.

       -   Run

             perl Makefile.PL

           which will prompt you for some settings. The really important ones
           are:

             Which DBMS do you want to use?

           enter a 1 here (MySQL only), and

             Where is your mysql installed? Please tell me the directory that
             contains the subdir include.

           where you have to enter the win32clients directory, for example
           C:\mysql or C:\tmp\mysql.

       -   Continued in the usual way:

             nmake
             nmake install

       If you want to create a PPM package for the ActiveState Perl version,
       then modify the above steps as follows: Run

         perl Makefile.PL NAME=DBD-mysql BINARY_LOCATION=DBD-mysql.tar.gz
         nmake ppd
         nmake

       Once that is done, use tar and gzip (for example those from the
       CygWin32 distribution) to create an archive:

         mkdir x86
         tar cf x86/DBD-mysql.tar blib
         gzip x86/DBD-mysql.tar

       Put the files x86/DBD-mysql.tar.gz and DBD-mysql.ppd onto some WWW
       server and install them by typing

         install http://your.server.name/your/directory/DBD-mysql.ppd

       in the PPM program.

AUTHORS
       The current version of DBD::mysql is almost completely written by
       Jochen Wiedmann, and is now being maintained by Patrick Galbraith
       (patg@mysql.com).  The first version's author was Alligator Descartes,
       who was aided and abetted by Gary Shea, Andreas Koenig and Tim Bunce
       amongst others.

       The Mysql module was originally written by Andreas Koenig
       <koenigATkulturbox.de>. The current version, mainly an emulation layer,
       is from Jochen Wiedmann.

COPYRIGHT
       This module is Large Portions Copyright (c) 2004-2006 MySQL Patrick
       Galbraith, Alexey Stroganov, Large Portions Copyright (c) 2003-2005
       Rudolf Lippan; Large Portions Copyright (c) 1997-2003 Jochen Wiedmann,
       with code portions Copyright (c)1994-1997 their original authors This
       module is released under the same license as Perl itself. See the Perl
       README for details.

MAILING LIST SUPPORT
       This module is maintained and supported on a mailing list,

           perlATlists.com

       To subscribe to this list, go to

       http://lists.mysql.com/perl?sub=1

       Mailing list archives are available at

       http://lists.mysql.com/perl

       Additionally you might try the dbi-user mailing list for questions
       about DBI and its modules in general. Subscribe via

       dbi-users-subscribeATperl.org

       Mailing list archives are at

       http://groups.google.com/group/perl.dbi.users?hl=en&lr=

       Also, the main DBI site is at

       http://dbi.perl.org/

ADDITIONAL DBI INFORMATION
       Additional information on the DBI project can be found on the World
       Wide Web at the following URL:

           http://dbi.perl.org

       where documentation, pointers to the mailing lists and mailing list
       archives and pointers to the most current versions of the modules can
       be used.

       Information on the DBI interface itself can be gained by typing:

           perldoc DBI

       right now!

BUG REPORTING, ENHANCEMENT/FEATURE REQUESTS
       Please report bugs, including all the information needed such as
       DBD::mysql version, MySQL version, OS type/version, etc to this link:

       http://bugs.mysql.com/

POD ERRORS
       Hey! The above document had some coding errors, which are explained
       below:

       Around line 1223:
           '=item' outside of any '=over'

       Around line 1274:
           You forgot a '=back' before '=head1'

       Around line 1516:
           You forgot a '=back' before '=head1'



perl v5.10.0                      2008-04-09                   DBD::mysql(3pm)