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      <h1>DBIx::Class Introduction</h1>
      <h2>YAPC::NA 2010</h2>
   </div>
</div>

<div class="presentation">

   <div class="slide">
      <h1>DBIX::Class (aka DBIC)</h1>
      <h3>for (advanced) beginners</h3>
   </div>

   <div class="slide">
      <h1>Contact Info</h1>
      <ul>
         <li>IRC: irc.perl.org #dbix-class</li>
         <li>ML: <a href="http://lists.scsys.co.uk/mailman/listinfo/dbix-class">http://lists.scsys.co.uk/mailman/listinfo/dbix-class</a></li>
         <li><a href="http://search.cpan.org/perldoc?DBIx::Class">DBIx::Class</a> yo</li>
      </ul>
   </div>

   <div class="slide">
      <h1>Authors</h1>
      <h4>Originally Leo Lapworth @ LPW 2009</h4>
      <h4>Amiri Barksdale</h4>
      <h4>Justin D. Hunter</h4>
      <h4>Arthur Axel "fREW" Schmidt</h4>
   </div>

   <div class="slide">
      <h1>What's up guys?</h1>
      <ul class="incremental">
         <li>How many people have used any ORM?</li><ul class="incremental">
            <li>In Perl?<ul class="incremental">
               <li>DBIC?</li>
               <li>Class::DBI?</li>
               <li>Rose::DB?</li>
               <li>Fey::ORM?</li>
               <li>Others?</li>
            </ul></li>
            <li>AR?</li>
            <li>(N)Hibernate?</li>
         </ul></li>
      </ul>
   </div>

   <div class="slide">
      <h1>Purpose</h1>
      <p>The purpose of this talk is to show you as many features of
      DBIx::Class in 40 minutes so that when you need to do something with
      it later you will know what's possible</p>
      <ul class="incremental">
         <li>Note: links in slides are so you can find docs for what I'm talking about later</li>
      </ul>
   </div>

   <div class="slide">
      <h1>DBIx::Class?</h1>
      <ul>
         <li>ORM (object relational mapper)</li>
         <li>SQL &lt;-&gt; OO (using objects instead of SQL)</li>
         <li>There are many ORMs, DBIx::Class just happens to be the best in Perl (personal opinion)</li>
      </ul>
   </div>

   <div class="slide">
      <h1>Meta</h1>
      <p>These are reasons that are not technical or inherent to
      the code of DBIC, but are totally awesome things about it.</p>
   </div>

   <div class="slide">
      <h1>Large Community</h1>
      <p>Currently there are 88 people listed as contributors to DBIC.  That
      ranges from documentation help, to test help, to added features,
      to entire database support.</p>
   </div>

   <div class="slide">
      <h1>Active Community</h1>
      <p>Currently (June 9, 2010) 6 active branches (commited to in the last two weeks) in git.  Last release (0.08122) had 14 new features, and 16 bug fixes.  Of course that <a href="http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits/DBIx-Class.git;a=blob;f=Changes">ebbs and flows</a>.</p>
   </div>

   <div class="slide">
      <h1>Responsive Community</h1>
      <ul class="incremental">
         <li>needed MSSQL order-by support, they helped me add support</li>
         <li>generally very welcoming of people willing to help</li>
      </ul>
   </div>

   <div class="slide">
      <h1>General ORM</h1>
      <p>These are things that are in most other ORMs, but are still reasons
      to use DBIC over raw SQL.</p>
   </div>

   <div class="slide">
      <h1>Cross DB</h1>
      <p>The vast majority of code should run on all databases without needing tweaking</p>
   </div>

   <div class="slide">
      <h1>Basic CRUD</h1>
      <ul class="incremental">
         <li><strong>C</strong> - Create</li>
         <li><strong>R</strong> - Read</li>
         <li><strong>U</strong> - Update</li>
         <li><strong>D</strong> - Delete</li>
      </ul>
   </div>

   <div class="slide">
      <h1>SQL: Create</h1>
<pre>my $sth = $dbh-&gt;prepare('
   INSERT INTO books
   (title, author_id)
   values (?,?)
');

$sth-&gt;execute(
  'A book title', $author_id
);</pre>
   </div>

   <div class="slide">
      <h1>DBIC: Create</h1>
<pre>my $book = $book_rs-&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::ResultSet#create">create</a>({
   title     =&gt; 'A book title',
   author_id =&gt; $author_id,
});</pre>
      <ul class="incremental">
         <li>No need to pair placeholders and values</li>
         <li>Automatically gets autoincremented id for you</li>
         <li>Transparently uses INSERT ... RETURNING for databases that support it</li>
      </ul>
   </div>

   <div class="slide">
      <h1>SQL: Read</h1>
<pre>my $sth = $dbh-&gt;prepare('
   SELECT title,
   authors.name as author_name
   FROM books, authors
   WHERE books.author = authors.id
');

while( my $book = $sth-&gt;fetchrow_hashref() ) {
  print 'Author of '
     . $book-&gt;{title}
     . ' is '
     . $book-&gt;{author_name}
     . "\n";
}</pre>
   </div>

   <div class="slide">
      <h1>DBIC: Read</h1>
<pre>my $book = $book_rs-&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::ResultSet#find">find</a>($book_id);

my $book = $book_rs-&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::ResultSet#search">search</a>({
   title =&gt; 'A book title',
}, { rows =&gt; 1 })-&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::ResultSet#next">next</a>;

my @books = $book_rs-&gt;search({
   author =&gt; $author_id,
})-&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::ResultSet#all">all</a>;

while( my $book = $books_rs-&gt;next ) {
 print 'Author of '
    . $book-&gt;title
    . ' is '
    . $book-&gt;author-&gt;name
    . "\n";
}
</pre>
      <ul class="incremental">
         <li>TMTOWTDI</li>
      </ul>
   </div>

   <div class="slide">
      <h1>SQL: Update</h1>
<pre>my $update = $dbh-&gt;prepare('
   UPDATE books
   SET title = ?
   WHERE id = ?
');

$update-&gt;execute(
  'New title',<strong>$book_id</strong>
);</pre>
   </div>

   <div class="slide">
      <h1>DBIC: Update</h1>
<pre>$book-&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::Row#update">update</a>({
  title =&gt; 'New title',
});</pre>
      <ul class="incremental">
         <li>Won't update unless value changes</li>
      </ul>
   </div>

   <div class="slide">
      <h1>SQL: Delete</h1>
<pre>my $delete = $dbh-&gt;prepare('
   DELETE FROM books
   WHERE id = ?
');

$delete-&gt;execute(<strong>$book_id</strong>);</pre>
   </div>

   <div class="slide">
      <h1>DBIC: Delete</h1>
<pre>$book-&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::Row#delete">delete</a>;</pre>
   </div>

   <div class="slide">
      <h1>SQL: Search</h1>
<pre>my $sth = $dbh-&gt;prepare('
   SELECT title,
   authors.name as author_name
   FROM books
   WHERE books.name LIKE "%monte cristo%" AND
   books.topic = "jailbreak"
');
</pre>
   </div>

   <div class="slide">
      <h1>DBIC: Search</h1>
<pre>
my $book = $book_rs-&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::ResultSet#search">search</a>({
   'me.name'  =&gt; { -like =&gt; '%monte cristo%' },
   'me.topic' =&gt; 'jailbreak',
})-&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::ResultSet#next">next</a>;
</pre>
      <ul class="incremental">
         <li><a href="http://search.cpan.org/perldoc?SQL::Abstract">SQL::Abstract</a></li>
         <li>(kinda) introspectible</li>
         <li>Prettier than SQL</li>
      </ul>
   </div>

   <div class="slide">
      <h1>OO Overidability</h1>
      <ul class="incremental">
         <li>Override new if you want to do validation</li>
         <li>Override delete if you want to disable deletion</li>
         <li>and on and on</li>
      </ul>
      <div class="notes">
         <p>I got yelled at about this before by people, so
         we don't get EVERYTHING from OO, but we do get a lot
         so :-P</p>
      </div>
   </div>

   <div class="slide">
      <h1>Convenience Methods</h1>
      <ul class="incremental">
         <li><a href="http://search.cpan.org/perldoc?DBIx::Class::ResultSet#find_or_create">find_or_create</a></li>
         <li><a href="http://search.cpan.org/perldoc?DBIx::Class::ResultSet#update_or_create">update_or_create</a></li>
      </ul>
   </div>

   <div class="slide">
      <h1>Non-column methods</h1>
      <p>Need a method to get a user's gravatar URL?  Add a
      gravatar_url method to their Result class</p>
   </div>

   <div class="slide">
      <h1>RELATIONSHIPS</h1>
      <ul class="incremental">
         <li><a href="http://search.cpan.org/perldoc?DBIx::Class::Relationship#belongs_to">belongs_to</a></li>
         <li><a href="http://search.cpan.org/perldoc?DBIx::Class::Relationship#has_many">has_many</a></li>
         <li><a href="http://search.cpan.org/perldoc?DBIx::Class::Relationship#might_have">might_have</a></li>
         <li><a href="http://search.cpan.org/perldoc?DBIx::Class::Relationship#has_one">has_one</a></li>
         <li><a href="http://search.cpan.org/perldoc?DBIx::Class::Relationship#many_to_many">many_to_many</a> (technically not a relationship)</li>
         <li>SET AND FORGET</li>
      </ul>
   </div>

   <div class="slide">
      <h1>DBIx::Class Specific Features</h1>
      <p>These things may be in other ORM's, but they are very specific, so doubtful</p>
   </div>

   <div class="slide">
      <h1>-&gt;deploy</h1>
      <p>Perl -&gt; DB</p>
<pre>my $schema = Foo::Schema-&gt;connect(
   $dsn, $user, $pass
);
$schema-&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::Schema#deploy">deploy</a>
</pre>
<p>See also: <a href="http://search.cpan.org/perldoc?DBIx::Class::DeploymentHandler">DBIx::Class::DeploymentHandler</a></p>
   </div>

   <div class="slide">
      <h1>Schema::Loader</h1>
      <p>DB -&gt; Perl</p>
<pre>package Foo::Schema;
use strict; use warnings;
use base '<a href="http://search.cpan.org/perldoc?DBIx::Class::Schema::Loader">DBIx::Class::Schema::Loader</a>';
__PACKAGE__-&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::Schema::Loader::Base#CONSTRUCTOR_OPTIONS">loader_options</a>({
   naming =&gt; 'v7',
   debug  =&gt; $ENV{DBIC_TRACE},
});
1;

# elsewhere...

my $schema = Foo::Schema-&gt;connect(
   $dsn, $user, $pass
);
</pre>
   </div>

   <div class="slide">
      <h1>Populate</h1>
      <p>Made for inserting lots of rows very quicky into database</p>
<pre>$schema-&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::Schema#populate">populate</a>([ Users =&gt;
   [qw( username password )],
   [qw( frew     &gt;=4char$ )],
   [qw(      ...          )],
   [qw(      ...          )],
);
</pre>
      <ul class="incremental">
         <li>I use this to <a href="http://blog.afoolishmanifesto.com/archives/1255">export our whole (200M~) db to SQLite</a></li>
      </ul>
   </div>

   <div class="slide">
      <h1>Multicreate</h1>
      <p>Create an object and all of it's related objects all at once</p>
<pre>$schema-&gt;resultset('Author')-&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::ResultSet#create">create</a>({
   name =&gt; 'Stephen King',
   books =&gt; [{ title =&gt; 'The Dark Tower' }],
   address =&gt; {
      street =&gt; '123 Turtle Back Lane',
      state  =&gt; { abbreviation =&gt; 'ME' },
      city   =&gt; { name =&gt; 'Lowell'     },
   },
});
</pre>
      <div class="notes">
         <ul>
            <li>books is a has_many</li>
            <li>address is a belongs_to which in turn belongs to state and city each</li>
            <li>for this to work right state and city must mark abbreviation and name as unique</li>
         </ul>
      </div>
   </div>

   <div class="slide">
      <h1>Extensible</h1>
      <p>DBIx::Class helped pioneer fast MI in Perl 5 with Class::C3, so it is made
      to allow extensions to nearly every part of it.</p>
   </div>

   <div class="slide">
      <h1>Extensible: DBIC::Helpers</h1>
      <ul class="incremental">
         <li><a href="http://search.cpan.org/perldoc?DBIx::Class::Helper::ResultSet::IgnoreWantarray">DBIC::Helper::ResultSet::IgnoreWantarray</a></li>
         <li><a href="http://search.cpan.org/perldoc?DBIx::Class::Helper::ResultSet::Random">DBIC::Helper::ResultSet::Random</a></li>
         <li><a href="http://search.cpan.org/perldoc?DBIx::Class::Helper::ResultSet::SetOperations">DBIC::Helper::ResultSet::SetOperations</a></li>
         <li><a href="http://search.cpan.org/perldoc?DBIx::Class::Helper::ResultSet::JoinTable">DBIC::Helper::Row::JoinTable</a></li>
         <li><a href="http://search.cpan.org/perldoc?DBIx::Class::Helper::ResultSet::NumifyGet">DBIC::Helper::Row::NumifyGet</a></li>
         <li><a href="http://search.cpan.org/perldoc?DBIx::Class::Helper::ResultSet::SubClass">DBIC::Helper::Row::SubClass</a></li>
         <li><a href="http://search.cpan.org/perldoc?DBIx::Class::Helper::ResultSet::ToJSON">DBIC::Helper::Row::ToJSON</a></li>
      </ul>
   </div>

   <div class="slide">
      <h1>Extensible: <a href="http://search.cpan.org/perldoc?DBIx::Class::TimeStamp">DBIC::TimeStamp</a></h1>
      <ul class="incremental">
         <li>Cross DB</li>
         <li>set_on_create</li>
         <li>set_on_update</li>
      </ul>
   </div>

   <div class="slide">
      <h1>Extensible: Kioku</h1>
      <ul class="incremental">
         <li><a href="http://search.cpan.org/perldoc?DBIx::Class::Schema::KiokuDB">DBIx::Class::Schema::KiokuDB</a></li>
         <li>Kioku is the new hotness</li>
         <li>Mix RDBMS with Object DB</li>
         <li>beta ( == sexy )</li>
      </ul>
   </div>

   <div class="slide">
      <h1>Result vs ResultSet</h1>
         <ul class="incremental">
            <li>Result == Row</li>
            <li>ResultSet == Query Plan<ul class="incremental">
               <li>Internal Join Optimizer for all DB's (!!!)</li>
            </ul></li>
            <li>(less important but...)</li>
            <li>ResultSource == Table</li>
            <li>Storage == Database</li>
         </ul>
   </div>

   <div class="slide">
      <h1><a href="http://search.cpan.org/perldoc?DBIx::Class::Manual::Cookbook#Predefined_searches">ResultSet methods</a></h1>
<pre>package MyApp::Schema::ResultSet::Book;
use base 'DBIx::Class::ResultSet';
sub good {
   my $self = shift;
   $self-&gt;search({
      $self-&gt;current_source_alias .
         '.rating' =&gt; { '&gt;=' =&gt; 4 },
   })
};
sub cheap {
   my $self = shift;
   $self-&gt;search({
      $self-&gt;current_source_alias .
         '.price' =&gt; { '&lt;=' =&gt; 5}
   })
};
# ...
1;
      </pre>
   </div>

   <div class="slide">
      <h1>ResultSet method notes</h1>
      <ul class="incremental">
         <li>All searches should be ResultSet methods</li>
         <li>Name has obvious meaning</li>
         <li><a href="http://search.cpan.org/perldoc?DBIx::Class::ResultSet#current_source_alias">current_source_alias</a> helps things to work no matter what</li>
      </ul>
   </div>

   <div class="slide">
      <h1>ResultSet method in Action</h1>
      <pre>$schema-&gt;resultset('Book')-&gt;good</pre>
   </div>

   <div class="slide">
      <h1>ResultSet Chaining</h1>
<pre>$schema-&gt;resultset('Book')
   -&gt;good
   -&gt;cheap
   -&gt;recent
</pre>
   </div>

   <div class="slide">
      <h1>search_related</h1>
<pre>my $score = $schema-&gt;resultset('User')
   -&gt;search({'me.userid' =&gt; 'frew'})
   -&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::ResultSet#related_resultset">related_resultset</a>('access')
   -&gt;related_resultset('mgmt')
   -&gt;related_resultset('orders')
   -&gt;telephone
   -&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::ResultSet#search_related">search_related</a>( shops =&gt; {
      'shops.datecompleted' =&gt; {
         -between =&gt; ['2009-10-01','2009-10-08']
      }
   })-&gt;completed
   -&gt;related_resultset('rpt_score')
   -&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::ResultSet#get_column">get_column</a>('raw_scores')
   -&gt;first;
</pre>
   </div>

   <div class="slide">
      <h1>bonus rel methods</h1>
<pre>my $book = $author-&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::Relationship::Base#create_related">create_related</a>(
   <strong>books</strong> =&gt; {
      title =&gt; 'Another Discworld book',
   }
);

my $book2 = $pratchett-&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::Relationship::Base#add_to_$rel">add_to_<strong>books</strong></a>({
   title =&gt; 'MOAR Discworld book',
});</pre>
      <ul class="incremental">
         <li>Automaticaly fills in foreign key for you</li>
      </ul>
   </div>

   <div class="slide">
      <h1>Excellent Transaction Support</h1>
<pre>$schema-&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::Schema#txn_do">txn_do</a>(sub {
   ...
});

my $guard = $schema-&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::Schema#txn_scope_guard">txn_scope_guard</a>;
# ...
$guard-&gt;commit;

$schema-&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::Schema#txn_begin">txn_begin</a>; # &lt;-- low level
# ...
$schema-&gt;<a href="http://search.cpan.org/perldoc?DBIx::Class::Schema#txn_commit">txn_commit</a>;
</pre>
   </div>

   <div class="slide">
      <h1>InflateColumn</h1>
<pre>package Foo::Schema::Result::Book;
use base 'DBIx::Class::Core';
use DateTime::Format::MySQL;
# Result code here
__PACKAGE__-&gt;load_components('<a href="http://search.cpan.org/perldoc?DBIx::Class::InflateColumn">InflateColumn</a>');
__PACKAGE__-&gt;<strong><a href="http://search.cpan.org/perldoc?DBIx::Class::InflateColumn#inflate_column">inflate_column</a></strong>(
   <strong>date_published</strong> =&gt; {
      inflate =&gt; sub {
         DateTime::Format::MySQL-&gt;parse_date(
            shift
         )
      },
      deflate =&gt; sub { shift-&gt;ymd },
   },
);
# Automatic see: DBIC::InflateColumn::DateTime</pre>
   </div>

   <div class="slide">
      <h1>InflateColumn: deflation</h1>
<pre>$book-&gt;date_published(DateTime-&gt;now);
$book-&gt;update;</pre>
   </div>

   <div class="slide">
      <h1>InflateColumn: inflation</h1>
<pre>say $book-&gt;date_published-&gt;month_abbr;</pre>

<strong><em>Nov</em></strong>
   </div>

   <div class="slide">
      <h1>FilterColumn</h1>
<pre>package Foo::Schema::Result::Book;
use base 'DBIx::Class::Core';
# Result code here
__PACKAGE__-&gt;load_components('<a href="http://search.cpan.org/perldoc?DBIx::Class::FilterColumn">FilterColumn</a>');

__PACKAGE__-&gt;<strong><a href="http://search.cpan.org/perldoc?DBIx::Class::FilterColumn#filter_column">filter_column</a></strong>(
   <strong>length</strong> =&gt; {
      to_storage   =&gt; 'to_metric',
      from_storage =&gt; 'to_imperial',
   },
);

sub to_metric   { $_[1] * .305 }
sub to_imperial { $_[1] * 3.28 }
   </div>

   <div class="slide">
      <h1><a href="http://search.cpan.org/perldoc?DBIx::Class::ResultSetColumn">ResultSetColumn</a></h1>
<pre>my $rsc = $schema-&gt;resultset('Book')
   -&gt;get_column('price');
$rsc-&gt;first;
$rsc-&gt;all;
$rsc-&gt;min;
$rsc-&gt;max;
$rsc-&gt;sum;
</pre>
   </div>

   <div class="slide">
      <h1>Aggregates</h1>
<pre>my @res = $rs-&gt;search({}, {
   <a href="http://search.cpan.org/perldoc?DBIx::Class::ResultSet#select">select</a>   =&gt; [
      'price',
      'genre',
      { max =&gt; price },
      { avg =&gt; price },
   ],
   <a href="http://search.cpan.org/perldoc?DBIx::Class::ResultSet#as">as</a>       =&gt; [
      qw(price genre max_price avg_price)
   ],
   <a href="http://search.cpan.org/perldoc?DBIx::Class::ResultSet#group_by">group_by</a> =&gt; [qw(price genre)],
});
for (@res) {
   say $_-&gt;price . ' ' . $_-&gt;genre;
   say $_-&gt;get_column('max_price');
   say $_-&gt;get_column('min_price');
}</pre>
   </div>

   <div class="slide">
      <h1>Aggregates Notes</h1>
      <ul class="incremental">
         <li>Careful, get_column can basicaly mean THREE things</li>
         <li>private for get what you should use an accessor for</li>
         <li>public for what there is no accessor for</li>
         <li>public for get resultset column (prev slide)</li>
      </ul>
   </div>

   <div class="slide">
      <h1>HRI</h1>
<pre>$rs-&gt;search({}, {
  <a href="http://search.cpan.org/perldoc?DBIx::Class::ResultSet#result_class">result_class</a> =&gt;
    '<a href="http://search.cpan.org/perldoc?DBIx::Class::ResultClass::HashRefInflator">DBIx::Class::ResultClass::HashRefInflator</a>',
});</pre>
      <ul class="incremental">
         <li>Easy on memory</li>
         <li>Mega fast</li>
         <li>Great for quick debugging</li>
         <li>Great for performance tuning (we went from 2m to &lt; 3s)</li>
      </ul>
   </div>

   <div class="slide">
      <h1><a href="http://search.cpan.org/perldoc?DBIx::Class::Manual::Cookbook#Subqueries">Subquery</a> Support</h1>
<pre>my $inside_query = $schema-&gt;resultset('Artist')
   -&gt;search({
    name =&gt; [ 'Billy Joel', 'Brittany Spears' ],
})-&gt;get_column('id')-&gt;as_query;

my $rs = $schema-&gt;resultset('CD')-&gt;search({
    artist_id =&gt; { -in =&gt; $inside_query },
});</pre>
   </div>

   <div class="slide">
      <h1><a href="http://search.cpan.org/perldoc?SQL::Abstract#Literal_SQL_with_placeholders_and_bind_values_(subqueries)">Bare SQL w/ Placeholders</a></h1>
<pre>$rs-&gt;update({
   # !!! SQL INJECTION VECTOR
   price =&gt; \"price + $inc",
});

$rs-&gt;update({
   price =&gt; \['price + ?', [inc =&gt; $inc]],
});
</pre>
   </div>

   <div class="slide">
      <h1>Questions?</h1>
   </div>

   <div class="slide">
      <h1>END</h1>
   </div>
</div>
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