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=encoding utf8

=head1 NAME

DBIx::Custom::Guide - DBIx::Custom Guide

=head1 GUIDE

B<This guide is now writing.>

L<DBIx::Custom> is the class to make easy to execute SQL.
This is L<DBI> wrapper class like L<DBIx::Class> or L<DBIx::Simple>.
You can do thing more easy than L<DBIx::Class>, more flexible
than L<DBIx::Simple>.

L<DBIx::Custom> is B<not< O/R mapper, O/R mapper is usefule, but
you must learn many things. Created SQL is sometimes inefficient,
and in many cases you create raw SQL because
O/R mapper can't make complex SQL

L<DBIx::Custom> is opposit of O/R mapper.
The main purpose is that we respect SQL
and make easy difficult works if you use only L<DBI>.
If you already learn SQL, it is easy to use L<DBIx::Custom>.

I explain L<DBIx::Custom> a little in this section.
In L<DBIx::Custom>, you embbed tag in SQL.

    select * from book where {= title} and {=author};

The part arround {} is tag.
This SQL is converted to the one which contains place holder.

    select * from book where title = ? and author = ?;

Maybe you ask me that this conversion is meaningful.
On the top of this, usuful features is implemented.
See the following descriptions.

=over 4

=item 1. Specify place holder binding value as hash refernce

If you use L<DBI>, you must specify place holder binding value
as array.

    $sth->execute(@bind);

If you use L<DBIx::Custom>, you specify it as hash reference.
    
    my $param = {title => 'Perl', author => 'Ken'};
    $dbi->execute($sql, $param);

=item 2. Filtering

L<DBIx::Custom> provides filtering system.
For example, You think that about date value you want to 
manipulate it as date object like L<Time::Piece> in Perl,
and want to convert it to database DATE format.
and want to do reverse.

You can use filtering system.

At first, register filter.

    $dbi->register_filter(
        tp_to_date => sub {
            ...
        },
        date_to_tp => sub {
            ...
        }
    );

next, apply this filter to each column.

    $dbi->apply_filter('book',
        'issue_date' => {out => 'tp_to_date', in => 'date_to_tp'}
    );

C<out> is perl-to-database way. C<in> is perl-from-database way.

This filter is automatically enabled in many method.

    $dbi->insert(table => 'book', param => {issue_date => $tp});


=item 3. Selective search condition

It is difficult to create selective where clause in L<DBI>.
For example, If C<title> and C<author> is specified, we create 
the following SQL.

    select * from book where title = ? and author = ?;

If only C<title> is specified, the following one

    select * from book where title = ?;

If only C<author> is specified, the following one,

    select * from book where author = ?;

This is hard work. Generally we use modules like L<SQL::Abstract>.
L<DBIx::Custom> prepare the way to make it easy.

    # Where object
    my $where = $dbi->where;
    
    # Search condition
    $where->clause(
        ['and', '{= title}', {'= author'}]
    );
    
    # Setting to automatically select needed column
    $where->param({title => 'Perl'});

    # Embbed where clause to SQL
    my $sql = "select * from book $where";

You can create where clause which has selected search condition.
You can write nesting of where clause and C<or> condition

=item 4. Method of insert, update, delete, select

L<DBIx::Custom>�ł�SQL���ɊȒP�Ɏ�s���邽�߂�
���\�b�h��񋟂��Ă��܂��B
C<insert()>, C<update()>, C<delete()>,C<select()>�Ȃǂ�
�V���K�[���\�b�h��g��āA�}��A�X�V�A�폜�A�I��Ƃ��������s�����Ƃ�
�ł��܂��B

    my $param = {title => 'Perl', author => 'Ken'};
    $dbi->insert(table => 'book', param => $param);

=item 5. �e�[�u���P�ʂ̑���̓o�^

�e�[�u���ɑ΂��đ����o�^���邱�Ƃ��ł��܂��B����ɂ���
�e�[�u������J��Ԃ��w�肷��K�v���Ȃ��Ȃ�A�\�[�X�R�[�h��
���ʂ����ǂ��Ȃ�܂��B

    $dbi->talbe('book',
        list => sub {
            ...
        },
        list_somethin => sub {
            
        }
    );

�o�^�������\�b�h�͂��̂܂ܗ��p���邱�Ƃ��ł��܂��B

    $dbi->table('book')->list;

�ʏ�O/R�}�b�p�̓e�[�u���ɑΉ�����N���X��쐬���Ȃ����
�Ȃ�Ȃ����Ƃ������ł����AL<DBIx::Custom>�ł͂��̍�Ƃ�ȕւ�
���Ă���A��L�̂悤�ɓo�^���邱�Ƃ��ł��܂��B

=back

L<DBIx::Custom>��L<DBI>��₤�ƂĂ�֗��ȃ��W���[���ł��B
��������ꂽ��́A���̌�ŏڂ�������s���܂��̂ŁA
�����ɂȂ�Ă݂Ă��������B

=head2 1. �f�[�^�x�[�X�ւ̐ڑ�

�܂�L<DBIx::Custom>��ǂݍ��݂܂��B

    use DBIx::Custom;

L<DBIx::Custom>�I�u�W�F�N�g�𐶐����A�f�[�^�x�[�X�ɐڑ�����ɂ�
C<connect()>���\�b�h��g�p���܂��B

    my $dbi = DBIx::Custom->connect(
        data_source => "dbi:mysql:database=dbname",
        user => 'ken',
        password => '!LFKD%$&',
        dbi_options => {mysql_enable_utf8 => 1}
    );

C<data_source>�̓f�[�^�x�[�X�V�X�e���ɉ������t�H�[�}�b�g��
�w�肷��K�v������܂��B�ȉ��Ƀf�[�^�x�[�X���Ƃ̃t�H�[�}�b�g
��@�̃T���v����f�ڂ��Ă����܂��B

B<MySQL>

    "dbi:mysql:database=$database"
    "dbi:mysql:database=$database;host=$hostname;port=$port"

B<SQLite>

    "dbi:SQLite:dbname=$database"
    "dbi:SQLite:dbname=:memory:"

B<PostgreSQL>

    "dbi:Pg:dbname=$dbname"

B<Oracle>

    "dbi:Oracle:$dbname"
    "dbi:Oracle:host=$host;sid=$sid"

B<ODBC(Microsoft Access)>

    "dbi:ODBC:driver=Microsoft Access Driver (*.mdb);dbq=hoge.mdb"

B<ODBC(SQL Server)>

   "dbi:ODBC:driver={SQL Server};Server=(local);database=test;Trusted_Connection=yes;AutoTranslate=No;"

�܂��F�؂����߂���ꍇ�́AC<user>��C<password>���[�U����
�p�X���[�h��w�肷��K�v������܂��B

L<DBIx::Custom>��L<DBI>�̃��b�p�ł��B
L<DBI>�̃f�[�^�x�[�X�n���h����C<dbh>�Ŏ擾���邱�Ƃ��ł��܂��B

    my $dbh = $dbi->dbh;

L<DBIx::Custom>�ł̓f�[�^�x�[�X�n���h�������ɂ̓f�t�H���g�Ŏ��̂�̂��ݒ肳��܂��B
    
    $dbi->dbh->{RaiseError} = 1;
    $dbi->dbh->{PrintError} = 0;
    $dbi->dbh->{AutoCommit} = 1;

���̐ݒ��s��Ă���̂ŁA�v���I�ȃG���[���N����ƁA
��O���������v���O�����͏I�����܂��B
�܂��N�G�������s�����Ǝ����I�ɃR�~�b�g����܂��B

=head2 2. �}��A�X�V�A�폜�A�I��̂��߂̃��\�b�h

L<DBIx::Custom>�́A
C<insert()>�AC<update()>�AC<delete()>�AC<select()>
�̂悤�ȑ}��A�X�V�A�폜�A�I���s�����߂̃��\�b�h���Ă��܂��B
�ȒP�Ȃ��Ƃ��s���̂ł���΁ASQL����ŋL�q����K�v������܂���B

=head3 �f�[�^�̑}�� C<insert()>

�f�[�^�x�[�X�Ƀf�[�^��}���ɂ�C<insert()>��g�p���܂��B

    $dbi->insert(table  => 'book',
                 param  => {title => 'Perl', author => 'Ken'});

C<table>�ɂ̓e�[�u�����AC<param>�ɂ͑}����f�[�^��w�肵�܂��B

����SQL�����s����܂��B

    insert into (title, author) values (?, ?);

=head3 �f�[�^�̍X�V C<update()>

�f�[�^�x�[�X�̃f�[�^��X�V����ɂ́AC<update()>��g�p���܂��B

    $dbi->update(table  => 'book', 
                 param  => {title => 'Perl', author => 'Ken'}, 
                 where  => {id => 5});

C<table>�ɂ̓e�[�u�����AC<param>�ɂ͑}����f�[�^�AC<where>�ɂ�
���w�肵�܂��B

����SQL�����s����܂��B

    update book set title = ?, author = ?;

C<update>���\�b�h�͈�S�̂���
where��̂Ȃ�SQL�𔭍s���邱�Ƃ�‚��Ă��܂���B
�����ׂĂ̍s��X�V�������ꍇ��
C<update_all()>��g�p�����������B

    $dbi->update_all(table  => 'book', 
                     param  => {title => 'Perl', author => 'Ken'});

=head3 �f�[�^�̍폜 C<delete()>

�f�[�^�x�[�X�̃f�[�^��1���폜����ɂ́AC<delete()>��g�p���܂��B

    $dbi->delete(table  => 'book',
                 where  => {author => 'Ken'});

C<table>�ɂ̓e�[�u�����AC<where>�ɂ͏��w�肵�܂��B

����SQL�����s����܂��B

    delete from book where id = ?;

C<delete>���\�b�h�͈�S�̂���
where��̂Ȃ�SQL�𔭍s���邱�Ƃ�‚��Ă��܂���B
�����ׂĂ̍s��폜�������ꍇ��
C<delete_all()>��g�p�����������B

    $dbi->delete_all(table  => 'book');

=head3 �f�[�^�̑I�� C<select()>

�s��I���ɂ�C<select()>��g�p���܂��B

    my $result = $dbi->select(table => 'book');

C<table>������w�肵�āA���̏��w�肵�Ȃ��ꍇ�͎���SQL�����s����܂��B

    select * from book;

C<select()>���\�b�h�̖߂�l��L<DBIx::Custom::Result>
�I�u�W�F�N�g�ł��B�s��t�F�b�`����ɂ�C<fetch()>��g�p���܂��B

    while (my $row = $result->fetch) {
        my $title  = $row->[0];
        my $author = $row->[1];
    }

L<DBIx::Custom::Result>�ɂ‚��Ă͂��̌�L<3. �s�̃t�F�b�`/"3. �s�̃t�F�b�`">�ŏڂ��������܂��B

���܂��܂�C<select()>�̎g�����Ă����܂��傤�B
����C<select>�͍s�̖��O��where���w�肵����̂ł��B

    my $result = $dbi->select(
        table  => 'book',
        column => ['author',  'title'],
        where  => {author => 'Ken'}
    );

C<column>�ɂ͗񖼂�AC<where>�ɂ͏��w�肷�邱�Ƃ��ł��܂��B
����SQL�����s����܂��B

    select author, title from book where author = ?;

�e�[�u������������ꍇ�͂�C<relation>�Ƀe�[�u����
�֌W��L�q���܂��B

    my $result = $dbi->select(
        table    => ['book', 'rental'],
        where    => {book.name => 'Perl'},
        relation => {'book.id' => 'rental.book_id'}
    );

book�e�[�u����id���rental�e�[�u����book_id���֘A�t�����܂��B
����SQL�����s����܂��B

    select * from book, rental where book.name = ? and book.id = rental.book_id;

SQL���̖���ɕ������lj�������ꍇ��<append>��g�p���܂��B

    my $result = $dbi->select(
        table  => 'book',
        where  => {author => 'Ken'},
        append => 'for update',
    );

����SQL�����s����܂��B

    select * book where author = ? for update;

�܂�C<append>�́AC<select>�����łȂ�C<insert()>�AC<update()>�AC<update_all()>
C<delete()>�AC<delete_all()>�AC<select()>�Ŏg�p���邱�Ƃ�ł��܂��B

=head3 SQL�̎�s C<execute()>

�C�ӂ�SQL���s����ɂ�execute���\�b�h��g�p���܂��B

    $dbi->execute("select * from book;");

C<execute()>��L<DBIx::Custom>�̍����̃��\�b�h�ł���^�O��W�J���܂��B

    $dbi->execute(
        "select * from book {= title} and {= author};"
        param => {title => 'Perl', author => 'Ken'}
    );

��L�̃^�O��܂�SQL�͎��̂悤�ɓW�J����܂��B

    select * from book title = ? and author = ?;

SQL����s�����Ƃ��Ƀv���[�X�z���_(?)�ɑΉ�����ʒu��title��author
�̒l���������I�ɖ��ߍ��܂�܂��B

�^�O�ɂ‚��Ă�L<5. �^�O/"5. �^�O">�ŏڂ�������܂����A
�ЂƂ‚̒��ӓ_������܂��B
�^�O��W�J���邽�߂�C<{>��C<}>�͗\���ɂȂ�Ă��܂��B
�����p�������ꍇ�͒��O��\����ăG�X�P�[�v��s���K�v������܂��B

    $dbi->execute("... \\{ ... \\} ...");

\���̂�Perl�̃G�X�P�[�v�����ł��̂ŁA��•K�v�ɂȂ�Ƃ����_�ɒ��ӂ��Ă��������B

�܂�execute�̃L���[�g�ȋ@�\�Ƃ��āASQL�̍Ō�ɃZ�~�R��������Ȃ��Ă�
���܂��܂���B

    $dbi->execute('select * from book');

=head2 3. �s�̃t�F�b�`

C<select()>���\�b�h�̖߂�l��L<DBIx::Custom::Result>�I�u�W�F�N�g�ł��B
L<DBIx::Custom::Result>�ɂ͍s��t�F�b�`���邽�߂̂��܂��܂ȃ��\�b�h��
�p�ӂ���Ă��܂��B

=head3 1�s�ƒt�F�b�`(�z��) C<fetch()>

��s�t�F�b�`���Ĕz��̃��t�@�����X�Ɋi�[����ɂ�C<fetch()>��g�p���܂��B

    while (my $row = $result->fetch) {
        my $title  = $row->[0];
        my $author = $row->[1];
    }

while���[�v��g��āA���ׂĂ̍s��擾���邱�Ƃ��ł��܂��B

=head3 �ŏ��̍s�����t�F�b�`(�z��) C<fetch_first()>

��s�����t�F�b�`���Ĕz��̃��t�@�����X�Ɋi�[����ɂ�C<fetch_first()>
��g�p���܂��B

    my $row = $result->fetch_first;

��s�̃t�F�b�`���I������͂���ȏ�t�F�b�`�ł��Ȃ��Ȃ�܂��B
���I�ɂ�1�s�̃t�F�b�`���I�������
�X�e�[�g�����g�n���h����C<finish()>����s����܂��B

=head3 �����s��Ƀt�F�b�`(�z��) C<fetch_multi()>

�����s��t�F�b�`���Ĕz��̃��t�@�����X��v�f�Ɏ���
�z��̃��t�@�����X�Ɋi�[����ɂ�C<fetch_multi()>��g�p���܂��B

    while (my $rows = $result->fetch_multi(2)) {
        my $title0   = $rows->[0][0];
        my $author0  = $rows->[0][1];
        
        my $title1   = $rows->[1][0];
        my $author1  = $rows->[1][1];
    }

��ɂ͎��o�������s����w�肵�܂��B

�w�肵���s��i�[�������̂悤�ȃf�[�^��擾�ł��܂��B

    [
        ['Perl', 'Ken'],
        ['Ruby', 'Mark']
    ]

=head3 ���ׂĂ̍s��t�F�b�`(�z��) C<fetch_all>

���ׂĂ̍s��t�F�b�`���Ĕz��̃��t�@�����X��v�f�Ɏ���
�z��̃��t�@�����X�Ɋi�[����ɂ�C<fetch_all()>��g�p���܂��B

    my $rows = $result->fetch_all;

���ׂĂ̍s��i�[�������̂悤�ȃf�[�^��擾�ł��܂��B

    [
        ['Perl', 'Ken'],
        ['Ruby', 'Mark']
    ]

=head3 1�s�ƒt�F�b�`(�n�b�V��) C<fetch_hash()>

��s�t�F�b�`���ăn�b�V���̃��t�@�����X�Ɋi�[����ɂ�C<fetch_hash()>��g�p���܂��B

    while (my $row = $result->fetch_hash) {
        my $title  = $row->{title};
        my $author = $row->{author};
    }

=head3 �ŏ��̍s�����t�F�b�`(�n�b�V��) C<fetch_hash_first()>

��s�����t�F�b�`���ăn�b�V���̃��t�@�����X�Ɋi�[����ɂ�
C<fetch_hash_first()>��g�p���܂��B

    my $row = $result->fetch_hash_first;

��s�̃t�F�b�`���I������͂���ȏ�t�F�b�`�ł��Ȃ��Ȃ�܂��B
���I�ɂ�1�s�̃t�F�b�`���I�������
�X�e�[�g�����g�n���h����C<finish()>����s����܂��B

=head3 �����s��Ƀt�F�b�`(�n�b�V��) C<fetch_hash_multi()>

�����s��t�F�b�`���ăn�b�V���̃��t�@�����X��v�f�Ɏ���
�z��̃��t�@�����X�Ɋi�[����ɂ�C<fetch_hash_multi()>
��g�p���܂��B

    while (my $rows = $result->fetch_hash_multi(5)) {
        my $title0   = $rows->[0]{title};
        my $author0  = $rows->[0]{author};
        my $title1  = $rows->[1]{title};
        my $author1 = $rows->[1]{author};
    }

��ɂ͎��o�������s����w�肵�܂��B

�w�肵���s��i�[�������̂悤�ȃf�[�^��擾�ł��܂��B

    [
        {title => 'Perl', author => 'Ken'},
        {title => 'Ruby', author => 'Mark'}
    ]

=head3 ���ׂĂ̍s��t�F�b�`(�n�b�V��) C<fetch_hash_all()>

���ׂĂ̍s��t�F�b�`���ăn�b�V���̃��t�@�����X��v�f�Ɏ���
�z��̃��t�@�����X�Ɋi�[����ɂ�C<fetch_hash_all()>
��g�p���܂��B

    my $rows = $result->fetch_hash_all;

���ׂĂ̍s��i�[�������̂悤�ȃf�[�^��擾�ł��܂��B

    [
        {title => 'Perl', author => 'Ken'},
        {title => 'Ruby', author => 'Mark'}
    ]

=head3 �X�e�[�g�����g�n���h�� C<sth()>

�X�e�[�g�����g�n���h���ɒ��ڃA�N�Z�X�������ꍇ��
<sth>�Ŏ擾���邱�Ƃ��ł��܂��B

    my $sth = $result->sth;

�t�F�b�`�̃p�t�H�[�}���X���p���𖞂����Ȃ��Ƃ��ɂ́A
�X�e�[�g�����g�n���h������
���p�ł��鑬�x�̑������\�b�h�𗘗p���邱�Ƃ��ł��܂��B

=head2 4. �t�B���^�����O

�f�[�^�x�[�X�Ƀf�[�^��o�^����Ƃ���f�[�^�x�[�X����f�[�^��擾����
�Ƃ��Ɏ����I�ɒl�̕ϊ���s�������ꍇ�������Ǝv���܂��B
���Ƃ��΁A��t��\�������̏ꍇ�́A
�f�[�^�x�[�X�ɓo�^����ꍇ��L<Time::Piece>�I�u�W�F�N�g����
�f�[�^�x�[�X�̓�t�̃t�H�[�}�b�g�ɁA
�f�[�^�x�[�X����f�[�^��擾����Ƃ��́A���̋t��s����ƕ֗��ł��B

=head3 �t�B���^�̓o�^ C<register_filter()>

�t�B���^��o�^����ɂ�C<register_filter()>��g�p���܂��B

    $dbi->register_filter(
        # Time::Piece object to DATE format
        tp_to_date => sub {
            my $date = shift;

            return '0000-00-00' unless $tp;
            return $tp->strftime('%Y-%m-%d');
        },
        
        # DATE to Time::Piece object
        date_to_tp => sub {
            my $date = shift;

            return if $date eq '0000-00-00';
            return Time::Piece->strptime($date, '%Y-%m-%d');
        },
    );

�o�^�����t�B���^��C<apply_filter()>�Ȃǂŗ��p���邱�Ƃ��ł��܂��B

=head3 �t�B���^�̓K�p C<apply_filter()>

�쐬�����t�B���^��K�p����ɂ́AC<apply_filter()>��g�p���܂��B

    $dbi->apply_filter('book',
        issue_date => {out => 'tp_to_date', in => 'date_to_tp'},
        first_issue_date => {out => 'tp_to_date', in => 'date_to_tp'}
    );

����̓e�[�u�����ł��B����ȍ~�́A�񖼂ƃt�B���^���[���̃y�A��L�q���܂��B
�t�B���^���[����out�ɂ́A�f�[�^�x�[�X�Ƀf�[�^�𑗐M����Ƃ��ɓK�p����t�B���^��A
�t�B���^���[����in�ɂ́A�f�[�^�x�[�X����f�[�^��擾����Ƃ��ɓK�p����t�B���^��
�L�q���܂��Bout���f�[�^�x�[�X�ɑ��M������Ain���f�[�^�x�[�X������o�����ł��B
�t�B���^�ɂ́AC<register_filter>�œo�^�����t�B���^���̑��ɁA�R�[�h���t�@�����X��
�w�肷�邱�Ƃ�ł��܂��B

    issue_date => {out => sub { ... }, in => sub { ... }}

�K�p���ꂽ�t�B���^��C<insert()>�AC<update()>�AC<update_all()>�AC<delete()>�A
C<delete_all()>�AC<select()>�ŗL��ɂȂ�܂��B

    my $tp = Time::Piece->strptime('2010/10/14', '%Y/%m/%d');
    my $result = $dbi->select(table => 'book', where => {issu_date => $tp});

�f�[�^�x�[�X�Ƀf�[�^�����M�����Ƃ��ɁAL<Time::Piece>�I�u�W�F�N�g��
�f�[�^�x�[�X�̓�t�̃t�H�[�}�b�g�u2010-10-14�v�ɕϊ�����܂��B

�܂��t�Ƀf�[�^��t�F�b�`����Ƃ��ɂ́A�f�[�^�x�[�X�̓�t�̃t�H�[�}�b�g��
�^�C���s�[�X�I�u�W�F�N�g�ɕϊ�����܂��B

    my $row = $resutl->fetch_hash_first;
    my $tp = $row->{issue_date};

���̂悤�Ȏ����I�Ɏ�s�����t�B���^��o�^�ł��邱�Ƃ�L<DBIx::Custom>��
����̂ЂƂ‚ł��B

C<apply_filter()>�œK�p���ꂽ�t�B���^�̓e�[�u�������܂ޗ񖼂ɑ΂��Ă�L��ł��B

    $dbi->select(
        table => 'book',
        where => {'book.title' => 'Perl', 'book.author' => 'Ken'}
    );

�e�[�u�����ʂ���K�v������Ƃ��ɕ֗��ȋ@�\�ł��B

=head3 �•ʂ̃t�B���^�̓K�p C<filter>

C<apply_filter()>��g��čŏ��ɂ��ׂẴe�[�u���̗�ɂ‚���
�t�B���^���`���邱�Ƃ�ł��܂����A
�•ʂɃt�B���^��K�p���邱�Ƃ�ł��܂��B
�•ʂ̃t�B���^��C<apply_filter()>�œK�p�����t�B���^��㏑���܂��B
�•ʂ̃t�B���^��SQL��as��g��āA��̕ʖ���쐬����K�v������ꍇ�Ɋ��􂵂܂��B

�f�[�^�x�[�X�ɑ��M����ꍇ�ɁA�•ʂ̃t�B���^��K�p����ɂ́A�e���\�b�h��
C<filter>�I�v�V������g�p���܂��B�•ʂ̃t�B���^�́AC<insert()>�AC<update()>�A
C<update_all()>�AC<delete()>�AC<delete_all()>�AC<select()>�AC<execute()>
�Ŏg�p���邱�Ƃ��ł��܂��B

C<insert()>�̗����܂��B

    $dbi->insert(
        table => 'book',
        param => {issue_date => $tp, first_issue_date => $tp},
        filter => {issue_date => 'tp_to_date', first_issue_date => 'tp_to_date'}
    );

C<execute()>�̗����܂��B

my $sql = <<"EOS";
select YEAR(issue_date) as issue_year
from book
where YEAR(issue_date) = {? issue_year}
EOS
   
    my $result = $dbi->execute(
        $sql,
        param => {issue_year => '2010'},
        filter => {issue_year => 'tp_to_year'}
    );

�����C<filter>��g���ǂ������ł��Bissue_date�̕ϊ��ɂ‚��Ă�C<apply_filter()>
�œo�^���Ă���̂ł����A�V�����쐬������ł���issue_year�ɂ‚��ẮA
���̕ϊ���o�^����Ă��܂���B�ł��̂ŁA�•ʂɃt�B���^��ݒ肵�Ă��܂��B

�܂����΂ɍs��t�F�b�`����Ƃ��ɂ�•ʂ̃t�B���^��K�p���邱�Ƃ��ł��܂��B
�t�B���^��K�p����ɂ́A
C<DBIx::Custom::Result>�N���X��C<filter>���\�b�h��g�p���܂��B

    $result->filter(issue_year => 'year_to_tp');

�p�ɂɗ��p����̂ł���΁A�•ʂɓo�^�������C<apply_filter()>�œo�^
���Ă������ق����֗��ł��傤�BC<apply_filter()>�͑��݂��Ȃ���ɑ΂��Ă�
�t�B���^��K�p�ł��邩��ł��B

    $dbi->apply_filter('book',
        'issue_year' => {out => 'tp_to_year', in => 'year_to_tp'}
    );

=head3 �ŏI�o�͂̂��߂̃t�B���^�����O C<end_filter()>

C<DBIx::Custom::Result>�ł͂���ɍŌ�ɂ���x�A�t�B���^��lj��
�o�^���邱�Ƃ��ł��܂��B���Ƃ���HTML�ɏo�͂������ꍇ�ɁATime::Piece
�I�u�W�F�N�g����ǂ݂₷���L�q�ɕϊ����邱�Ƃ��ł��܂��B
�Ō�̃t�B���^��o�^����ɂ́AC<end_filter()>��g�p���܂��B

    $result->end_filter(issue_date => sub {
        my $tp = shift;
        
        return '' unless $tp;
        return $tp->strftime('%Y/%m/%d %h:%m:%s (%a)');
    });

��t��₷���`�Ƀt�H�[�}�b�g���邱�Ƃ��ł��܂��B

�t�B���^�̓t�F�b�`��s���O�ɓo�^���Ă����K�v�����邱�Ƃ�
���ӂ��Ă��������B

    $result->filter(...);
    $result->end_filter(...);
    my $row = $result->fetch_hash_first;

=head3 ��̏���Ƀt�B���^��K�p���� C<each_column()>

��t�^�̗�͎蓮�Őݒ肵�Ȃ��Ă�A�����I�ɐݒ�ł���ƕ֗��ł��B
���̂��߂Ƀf�[�^�x�[�X�̃e�[�u���̗�̂��ׂĂ̏���
���Ԃɏ������邽�߂�C<each_column()>������܂��B

    $dbi->each_column(
        sub {
            my ($self, $table, $column, $info) = @_;
            
            my $type = $info->{TYPE_NAME};
            
            my $filter = $type eq 'DATE'     ? {out => 'tp_to_date', in => 'date_to_tp'}
                       : $type eq 'DATETIME' ? {out => 'tp_to_datetime', in => 'datetime_to_tp'}
                                             : undef;
            
            $self->apply_filter($table, $column, $filter)
              if $filter;
        }
    );

each_column�̓R�[���o�b�N��󂯎��܂��B�R�[���o�b�N�̈��
���Ԃ�L<DBIx::Custom>�I�u�W�F�N�g�A�e�[�u�����A�񖼁A��̏��ł��B
��̌^���̏����ƂɎ����I�ɁA�t�B���^��K�p���Ă��܂��B

�ЂƂ‚̒��ӓ_�Ƃ��ăR�[���o�b�N�̒�����A�R�[���o�b�N�̊O��
�̕ϐ���Q�Ƃ��Ȃ��悤�ɒ��ӂ��Ă��������Beach_column��
���X1�񂾂���s����邾���Ȃ̂ŁA�قƂ�ǂ̏ꍇ��肠��܂��񂪁A
�z�ŽQ�Ƃɂ�郁�������[�N���������Ă��܂��”\�����Ă��邩��ł��B

=head2 5. �^�O

=head3 �^�O�̋@�\

L<DBIx::Custom>��SQL�̒��Ƀ^�O�𖄂ߍ��ދ@�\���Ă��܂��B

    select * from book where {= title} and {like author};

{= title}��{like author}�̕������^�O�ł��B�^�O�͎��̂悤�Ȍ`��
����܂��B

    {�^�O�� ��1 ��2 ...}
    
�^�O��C<{>�Ŏn�܂�AC<}>�ŏI���܂��B�ŏ���C<{>�ƃ^�O���̊�
�ɂ͋󔒂�}��Ȃ��悤���ӂ��Ă��������B

�^�O�̋@�\�̂��߂�C<{>��C<}>�͗\���ɂȂ�Ă��܂��B
�����p�������ꍇ�͒��O��\����ăG�X�P�[�v��s���K�v������܂��B

    select from book \\{ ... \\}

C<\>���̂�Perl�̃G�X�P�[�v�����ł��̂ŁA
�G�X�P�[�v����ꍇ��C<\>����•K�v�ɂȂ�Ƃ����_�ɒ��ӂ��Ă��������B

��L�̃^�O��SQL����s�����O�Ɏ���SQL�ɓW�J����܂��B

    select * from book where title = ? and author like ?;

�^�O��܂�SQL���s����ɂ�C<execute()>��g�p���܂��B

    my $sql = "select * from book where {= author} and {like title};"
    $dbi->execute($sql, param => {title => 'Perl', author => '%Ken%'});

C<param>�I�v�V������g��āA�v���[�X�z���_�ɖ��ߍ��݂����l��
�n�b�V�����t�@�����X�Ŏw�肷�邱�Ƃ��ł��܂��B

���̃��\�b�h�Ɠ��l��C<execute()>�ɂ����Ă�C<filter>��w�肷�邱�Ƃ��ł��܂��B

    $dbi->execute($sql, param => {title => 'Perl', author => '%Ken%'}
                  filter => {title => 'to_something');

C<execute>�̂ЂƂ‚̒��ӓ_�Ƃ��Ă�C<apply_filter()>�œK�p���ꂽ�t�B���^
�̓f�t�H���g�ł͗L��ł͂Ȃ��Ƃ������Ƃɒ��ӂ��Ă��������B
C<apply_filter()>�œK�p���ꂽ�t�B���^��L��ɂ���ɂ́A
C<table>��w�肷��K�v������܂��B

    $dbi->execute($sql, param => {title => 'Perl', author => '%Ken%'}
                  table => ['book']);

=head2 �^�O�ꗗ

L<DBIx::Custom>�ł͎��̃^�O���g�p�”\�ł��B

���̂悤�Ƀ^�O��g���SQL����\������̂�L<DBIx::Custom>��
����ł��B�ȉ��̃^�O�����p�”\�ł��B

=head3 C<?>

C<?>�^�O�͈ȉ��̂悤�ɓW�J����܂��B

    {? NAME}    ->   ?

=head3 C<=>

C<=>�^�O�͈ȉ��̂悤�ɓW�J����܂��B

    {= NAME}    ->   NAME = ?

=head3 C<E<lt>E<gt>>

C<E<lt>E<gt>>�^�O�͈ȉ��̂悤�ɓW�J����܂��B

    {<> NAME}   ->   NAME <> ?

=head3 C<E<lt>>

C<E<lt>>�^�O�͈ȉ��̂悤�ɓW�J����܂��B

    {< NAME}    ->   NAME < ?

=head3 C<E<gt>>

C<E<gt>>�^�O�͈ȉ��̂悤�ɓW�J����܂��B

    {> NAME}    ->   NAME > ?

=head3 C<E<gt>=>

C<E<gt>=>�^�O�͈ȉ��̂悤�ɓW�J����܂��B

    {>= NAME}   ->   NAME >= ?

=head3 C<E<lt>=>

C<E<lt>=>�^�O�͈ȉ��̂悤�ɓW�J����܂��B

    {<= NAME}   ->   NAME <= ?

=head3 C<like>

C<like>�^�O�͈ȉ��̂悤�ɓW�J����܂��B

    {like NAME}   ->   NAME like ?

=head3 C<in>

C<in>�^�O�͈ȉ��̂悤�ɓW�J����܂��B�v���[�X�z���_��
�����Ŏw�肷��K�v�����邱�Ƃɒ��ӂ��Ă��������B

    {in NAME COUNT}   ->   NAME in [?, ?, ..]

=head3 C<insert_param>

C<insert_param>�^�O�͈ȉ��̂悤�ɓW�J����܂��B

    {insert_param NAME1 NAME2}   ->   (NAME1, NAME2) values (?, ?)

=head3 C<update_param>

C<update_param>�^�O�͈ȉ��̂悤�ɓW�J����܂��B

    {update_param NAME1 NAME2}   ->   set NAME1 = ?, NAME2 = ?

=head2 �����̗�̈���

�����̗��܂ރ^�O������ꍇ�ɂ�ASQL���s���邱�Ƃ��ł��܂��B
���Ƃ��΁A��‚̓�t�Ŕ�r���Ȃ���΂Ȃ�Ȃ��ꍇ��
�l���Č��܂��傤�B

    my $sql = "select * from table where {> date} and {< date};";

���̂悤�ȏꍇ�͑Ή�����p�����[�^�̒l��z��̃��t�@�����X�ɂ��܂��B

    my $dbi->execute($sql, param => {date => ['2010-10-01', '2012-02-10']});

=head2 �^�O�̒lj� C<register_tag()>

L<DBIx::Custom>�ł̓^�O��Ǝ��ɒlj���邱�Ƃ��ł��܂��B
�^�O��lj����ɂ�C<register_tag()>��g�p���܂��B

    $dbi->register_tag(
        '=' => sub {
            my $column = shift;
            
            return ["$column = ?", [$column]];
        }
    );

�����ł̓f�t�H���g��C<=>�^�O���ǂ̂悤�Ɏ������Ă��邩����Ă��܂��B
�^�O��o�^����֐��̈�̓^�O�̒��ɏ����ꂽ��ɂȂ�܂��B

    {�^�O�� ��1 ��2}

C<=>�^�O�̏ꍇ��

    {= title}

�Ƃ����`���ł�����A�T�u���[�`���ɂ�title�Ƃ����ЂƂ‚̗񖼂��킽��Ă��܂��B

�T�u���[�`���̖߂�l�ɂ͎��̌`���̔z��̃��t�@�����X��Ԃ��K�v������܂��B

    [
        �W�J��̕�����,
        [�v���[�X�z���_�ɖ��ߍ��݂ɗ��p�����1, ��2, ...]
    ]

��–ڂ̗v�f�͓W�J��̕�����ł��B���̗�ł�

    'title = ?'

��Ԃ��K�v������܂��B

��–ڂ̗v�f�̓v���[�X�z���_�ɖ��ߍ��݂ɗ��p����񖼂�܂ޔz���
���t�@�����X�ł��B����̗�ł�

    ['title']

��Ԃ��K�v������܂��B�����̃v���[�X�z���_��܂ޏꍇ�́A���̕�����
�����ɂȂ�܂��BC<insert_param>�^�O��C<update_param>�^�O��
���̕�������ە����ɂȂ�Ă��܂��B

��L��킹���

    ['title = ?', ['title']]
    
��Ԃ��K�v������Ƃ������Ƃł��B

�^�O�̎���̑��̃T���v����L<DBIx::Custom::Tag>�̃\�[�X�R�[�h
����ɂȂ�Ă݂Ă��������B

=head2 6. Where��̓��I�Ȑ���

=head3 Where��̓��I�Ȑ��� where()

�����̌�����w�肵�āA�����s�������ꍇ������܂��B
����3�‚̃P�[�X��where���l���Ă݂܂��傤�B
���L�̂悤��where�傪�K�v�ɂȂ�܂��B

title�̒l�����Ō�������ꍇ

    where {= title}

author�̒l�����Ō�������ꍇ

    where {= author}

title��author�̗���̒l�Ō�������ꍇ

    where {= title} and {=author}

L<DBIx::Custom>�ł͓��I��Where��̐�����T�|�[�g���Ă��܂��B
�܂�C<where()>��L<DBIx::Custom::Where>�I�u�W�F�N�g�𐶐����܂��B

    my $where = $dbi->where;

����C<clause()>��g�p����where���L�q���܂��B

    $where->clause(
        ['and', '{= title'}, '{= author}']
    );

clause�̎w���@�͎��̂悤�ɂȂ�܂��B

    ['or' ���邢�� 'and', �^�O1, �^�O2, �^�O3]

����ɂ�or���邢��and��w�肵�܂��B����ȍ~�ɂ�
������^�O��g��ċL�q���܂��B

C<clause>�̎w��͓��q�ɂ��邱�Ƃ�ł��A����ɕ��G�ȏ�
��L�q���邱�Ƃ�ł��܂��B

    ['and', 
      '{= title}', 
      ['or', '{= author}', '{like date}']
    ]

���̂悤��C<clause>��ݒ肵�����C<param>�Ƀp�����[�^��w�肵�܂��B
    
    my $param => {title => 'Perl'};
    $where->param($param);

���̗�ł�title�������p�����[�^�Ɋ܂܂�Ă��܂��B

���̌�C<to_string()>���s�����$param�Ɋ܂܂��p�����[�^�𖞂���
where��𐶐����邱�Ƃ��ł��܂��B

    my $where_clause = $where->to_string;

�p�����[�^��title�����ł��̂ŁA���̂悤��where�傪��������܂��B

    where {= title}

�܂�L<DBIx::Custom>�͕�����̕]����I�[�o�[���[�h���āAC<to_string()>
��Ăяo���悤�ɂ��Ă��܂��̂ŁA���̂悤�ɂ���where��𐶐����邱�Ƃ�
�ł��܂��B

    my $where_clause = "$where";

�����SQL�̒���where��𖄂ߍ��ނƂ��ɂƂĂ�𗧂‹@�\�ł��B

=head3 ����̗񖼂�܂ޏꍇ

�^�O�̒��ɓ���̖��O��‚�̂����݂����ꍇ�ł��I��
where���쐬���邱�Ƃ��ł��܂��B

���Ƃ��΁A�p�����[�^�Ƃ��ĊJ�n��t�ƏI����t��󂯎������Ƃ�
�l���Ă݂Ă��������B

    my $param = {start_date => '2010-11-15', end_date => '2011-11-21'};

�܂��J�n��t�ƏI����t�̕Е���A�ǂ����󂯎��Ȃ��ꍇ���邩����܂���B

���̏ꍇ�͎��̂悤�ȃp�����[�^�ɕϊ����邱�ƂőΉ����邱�Ƃ��ł��܂��B

    my $p = {date => ['2010-11-15', '2011-11-21']};

�l���z��̃��t�@�����X�ɂȂ�Ă��邱�Ƃɒ��ڂ��Ă��������B���̂悤�ɂ����
�����̗��܂ރ^�O�ɏ��Ԃɖ��ߍ��ނ��Ƃ��ł��܂��B

    $where->clause(
        ['and', '{> date}', '{< date}']
    );
    $where->param($p);

�܂��J�n��t�����݂��Ȃ��ꍇ�͎��̂悤�ȃf�[�^��쐬���܂��B

    my $p = {date => [$dbi->not_exists, '2011-11-21']};

L<DBIx::Custom>��C<not_exists>��DBIx::Custom::NotExists�I�u�W�F�N�g��
�擾�ł��܂��B����͑Ή�����l�����݂��Ȃ����Ƃ�����߂̂�̂ł��B

�܂��I����t�����݂��Ȃ��ꍇ�͎��̂悤�ȃf�[�^��쐬���܂��B

    my $p = {date => ['2010-11-15']};

�ǂ�����݂��Ȃ��ꍇ�͎��̂悤�ȃf�[�^��쐬���܂��B

    my $p = {date => []};

��������̂ň�ԊȒP�ɍ쐬�ł��郍�W�b�N����Ă����܂��B

    my @date;
    push @date, exists $param->{start_date} ? $param->{start_date}
                                            : $dbi->not_exists;
    push @date, $param->{end_date} if exists $param->{end_date};
    my $p = {date => \@date};

=head3 C<select()>�Ƃ̘A�g

L<DBIx::Custom::Where>�I�u�W�F�N�g��
C<select()>��C<where>�ɒ��ړn�����Ƃ�
�ł��܂��B
    
    my $where = $dbi->where;
    $where->clause(...);
    $where->param($param);
    my $result = $dbi->select(table => 'book', where => $where);

���邢��C<update()>�AC<delete()>��where�Ɏw�肷�邱�Ƃ�”\�ł��B

=head3 C<execute()>�Ƃ̘A�g

C<execute()>�Ƃ̘A�g�ł��BSQL��쐬����Ƃ��ɖ��ߍ��ނ��Ƃ��ł��܂��B


    my $where = $dbi->where;
    $where->clause(...);
    $where->param($param);

    my $sql = <<"EOS"
    select * from book;
    $where
    EOS

    $dbi->execute($sql, param => $param);

=head2 7. �e�[�u�����f��

=head3 �e�[�u���I�u�W�F�N�g�̍쐬 C<table()>

L<DBIx::Custom>�̓��W�b�N�Ƃ��ăe�[�u���𒆐S�ɂ�����
���f���̍쐬��x�����܂��B

�A�v���P�[�V�����̃��W�b�N��L�q����Ƃ��ɁA���̃��W�b�N��
�f�[�^�x�[�X�̃e�[�u���ɂ����邱�Ƃ́ARDBMS�𗘗p����
���f���ł���΁A�R�[�h�̏d�����Ȃ�
�킩��₷����̂ɂȂ�܂��B

�e�[�u���I�u�W�F�N�g�𐶐�����ɂ�C<table()>��g�p���܂��B

    my $table = $dbi->table('book');

��ۂɃf�[�^�x�[�X�Ƀe�[�u���͑��݂��Ă���K�v�͂���܂���B
����͉��z�I�ȃe�[�u���I�u�W�F�N�g�ł��B�����
L<DBIx::Customm::Table>�I�u�W�F�N�g�ɂȂ�܂��B

�e�[�u���I�u�W�F�N�g�����C<insert()>�AC<update()>�AC<update_all()>�A
C<delete()>�AC<delete_all()>�AC<select()>�Ȃǂ̃��\�b�h�Ăяo�����Ƃ��ł��܂��B
L<DBIx::Custom>�ƈقȂ�Ƃ���́AC<table>��K������w�肷��K�v��
�Ȃ��Ƃ������Ƃł��B

    $table->insert(param => $param);

C<table���̒l�͎����I��book�ɐݒ肳��܂��B

�܂��e�[�u���I�u�W�F�N�g�ɂ͓Ǝ��̃��\�b�h��lj���邱�Ƃ��ł��܂��B

    $table->method(
        register => sub {
            my $self = shift;
            my $table_name = $self->name;
            # something
        },
        list => sub {
            my $self = shift;
            my $table_name = $self->name;
            # something
        }
    );

���\�b�h�ɓn���������L<DBIx::Custom::Table>�I�u�W�F�N�g�ł��B
C<name()>��g�p���āA�e�[�u������擾���邱�Ƃ��ł��܂��B

���̂悤�ɂ��ēo�^�������\�b�h�͒��ڌĂяo�����Ƃ��ł��܂��B

    $table->register(...);
    $table->list(...);

�܂��e�[�u����p�̃��\�b�h��I�[�o�[���C�h���č쐬���邱�Ƃ�ł��܂��B

    $table->method(
        insert => sub {
            my $self = shift;
            
            $self->base_insert(...);
            
            # something
        }
    );

��Ƃ�Ƒ��݂��Ă���C<insert()>��ĂԂɂ�C<base_$method>�Ƃ��܂��BL<DBIx::Custom::Table>
�̃I�[�o�[���C�h�̋@�\�͊ȈՓI�Ȃ�̂ł����A�ƂĂ�֗��ł��B

=head2 �e�[�u���ŋ��L�̃��\�b�h�̓o�^

���ׂẴe�[�u���Ń��\�b�h��L����ɂ�C<table>���\�b�h�Ńe�[�u����쐬����O�ɁA
C<base_table>�Ƀ��\�b�h��o�^���Ă����܂��B

    $dbi->base_table->method(
        count => sub {
            my $self = shift;
            return $self->select(column => ['count(*)']);
        }
    );

�܂��e�[�u�������L<DBIx::Custom>��L<DBI>�̂��ׂẴ��\�b�h��Ăяo�����Ƃ��ł��܂��B

    # DBIx::Custom method
    $table->execute($sql);
    
    # DBI method
    $table->begin_work;
    $table->commit;

=head2 ��ʓI�ȃ��f���̍\��

��ʓI�ɂ́AL<DBIx::Custom>��p�����ăR���X�g���N�^�̒��ɁA���f����쐬
����̂��悢�ł��傤�B

    package MyDBI;
    
    use base 'DBIx::Custom';
    
    sub connect {
        my $self = shift->SUPER::connect(@_);
        
        $self->base_table->method(
            ... => sub { ... }
        );
        
        $self->table('book')->method(
            insert_multi => sub { ... },
            ... => sub { ... }
        );
        
        $self->table('company')->method(
            ... => sub { ... },
        );
    }

���̂悤�ɂ��Ē�`���Ă����΁A���̂悤�ɗ��p���邱�Ƃ��ł��܂��B

    my $dbi = MyDBI->connect(...);
    $dbi->table('book')->insert_multi(...);

=head2 8. �p�t�H�[�}���X�̉�P

=head3 �N�G���̍쐬

��C<insert()>���\�b�h��g�p���ăC���T�[�g���s�����ꍇ�A
�K�v�ȃp�t�H�[�}���X�𓾂��Ȃ��ꍇ�����邩����܂���B
C<insert()>���\�b�h�́ASQL���ƃX�e�[�g�����g�n���h����
����쐬���邽�߂ł��B

���̂悤�ȏꍇ�́AC<query>�I�v�V������w�肷�邱�ƂŁA
�N�G����擾���邱�Ƃ��ł��܂��B

    my $query = $dbi->insert(table => 'book', param => $param, query => 1);

�܂�C<create_query()>���\�b�h��g��ĔC�ӂ�SQL�̃N�G����쐬
���邱�Ƃ�ł��܂��B

    my $query = $dbi->create_query(
        "insert into book {insert_param title author};";
    );

�߂�l��L<DBIx::Custom::Query>�I�u�W�F�N�g�ł��B
���̃I�u�W�F�N�g��SQL���ƃp�����[�^�o�C���h���̗񖼂�
�ێ����Ă��܂��B�܂��X�e�[�g�����g�n���h����ێ����Ă��܂��B

    {
        sql     => 'insert into book (title, author) values (?, ?);',
        columns => ['title', 'author'],
        sth     => $sth
    }

�N�G���I�u�W�F�N�g��g��ČJ��Ԃ���s����ɂ�C<execute()>��g�p���܂��B
    
    my $params = [
        {title => 'Perl',      author => 'Ken'},
        {title => 'Good days', author => 'Mike'}
    ];
    
    foreach my $param (@$paramss) {
        $dbi->execute($query, table => 'book', param => $input);
    }

C<execute>���\�b�h�̑���ɃN�G���I�u�W�F�g��n�����Ƃ��ł��܂��B
C<insert()>���\�b�h�������ł��B

���ӓ_�������‚�����܂��B����̓p�����[�^�̐��͕K�������łȂ��Ă͂Ȃ�Ȃ�
�Ƃ������Ƃł��B�ŏ���3�‚̃p�����[�^������n�����̂ɁA���̎�s�ł�
��‚̃p�����[�^��n���Ɨ\��Ȃ����ʂɂȂ�܂��B�����
���I�ɐ������ꂽSQL�Ɋ܂܂��v���[�X�z���_�̐����قȂ邩��ł��B
�܂�C<execute()>�ɂ��Ă͎����I�ɂ̓t�B���^���L��ɂȂ�Ȃ��̂ŁA
C<table>��w�肷��K�v�̂��邱�Ƃɒ��ӂ��Ă��������B
�{���ɕK�v�ȏꍇ�������p���Ă��������B

=head2 9. ���̑��̋@�\

=head3 ���\�b�h�̓o�^

���\�b�h��o�^����ɂ�C<method()>��g�p���܂��B

    $dbi->method(
        update_or_insert => sub {
            my $self = shift;
            # something
        },
        find_or_create   => sub {
            my $self = shift;
            # something
        }
    );

<method()>�œo�^�������\�b�h��
L<DBIx::Custom>�I�u�W�F�N�g���璼�ڌĂяo�����Ƃ��ł��܂��B

    $dbi->update_or_insert;
    $dbi->find_or_create;

=head3 ���ʃN���X�̕ύX

�K�v�Ȃ�Ό��ʃN���X��ύX���邱�Ƃ��ł��܂��B

    package MyResult;
    use base 'DBIx::Custom::Result';
    
    sub some_method { ... }

    1;
    
    package main;
    
    use MyResult;
    
    my $dbi = DBIx::Custom->connect(...);
    $dbi->result_class('MyResult');

=head3 �L���b�V���O

�^�O�̓W�J���SQL�̓p�t�H�[�}���X�̗��R�̂��߂ɃL���b�V������܂��B
�����C<chace>�Őݒ�ł��A�f�t�H���g�ł̓L���b�V����s���ݒ�ł��B

    $dbi->cache(1);

�L���b�V����@��C<cache_method>�Ƀ��\�b�h��w�肷�邱�Ƃ�
�ύX���邱�Ƃ��ł��܂��B
�f�[�^�̕ۑ��Ǝ擾�̂��߂̃��\�b�h���`���܂��B

�f�t�H���g�ł͎��̂悤�Ƀ�������ɃL���b�V����s����̂ɂȂ�Ă��܂��B

    $dbi->cache_method(sub {
        sub {
            my $self = shift;
            
            $self->{_cached} ||= {};
            
            if (@_ > 1) {
                # Set
                $self->{_cached}{$_[0]} = $_[1] 
            }
            else {
                # Get
                return $self->{_cached}{$_[0]}
            }
        }
    });
    
����L<DBIx::Custom>�I�u�W�F�N�g�ł��B
����̓^�O�̓W�J�����O��SQL�ł��B
��O��̓^�O�̓W�J���SQL�ł��B

�����ō쐬����ꍇ�͑�O�����݂����ꍇ�̓L���b�V����ݒ肵�A
���݂��Ȃ�����ꍇ�̓L���b�V����擾��������
�����������B

=cut

=head1 EXAMPLES

L<DBIx::Custom Wiki|https://github.com/yuki-kimoto/DBIx-Custom/wiki> - Many useful examples

=cut