--- /dev/null
+## Removed from UPDATE.pod:
+
+=head2 Update a row or rows using a column calculation
+
+ -- Yet another pointless example
+ UPDATE users
+ SET username = username || '.uk'
+ WHERE id = 1;
+
+=over
+
+=item 1. Create a Schema object representing the database you are working with:
+
+ my $schema = MyDatabase::Schema->connect('dbi:SQLite:my.db');
+
+=item 2. Call the B<find> method on the resultset for the L<ResultSource|DBIx::Class::ResultSource> you wish to fetch data from:
+
+ my $fred_user = $schema->resultset('User')->find({ id => 1 });
+
+The Row object has an B<update> method that will change the values on
+the object, and send an UPDATE query to the database.
+
+=item 3. Call the B<update> method, passing it a hashref of new data:
+
+# this won't yet work, DBIC for now mandates the [ {} => $value ] format, the simple \[ $sql, $value1, $value2 ] will start being recognized later on
+# the only documentation we currently have is this, if you can turn it into a DBIC pod-patch it will be freaking awesome
+# https://github.com/dbsrgits/dbix-class/commit/0e773352
+ $fred_user->update({ username => \['username || ?', '.uk'] });
+
+^^ you never got around to this
+
+# the DBIC syntax is a tad different from te thing above (i.e. we no longer encourage 'dummy' crap)
+The \[ .. ] syntax here is described in L<SQL::Abstract>
+documentation, used for passing bind parameters.
+
+
+=back
+
+=head2 Update a row based on data in other tables
+
+ -- Slightly less pointless example
+ UPDATE posts
+ SET title = user.username || title
+ JOIN users user ON user.id = posts.user_id;
+
+Joining two tables for an update is a similar sort of exercise to
+joining them for a select query and using data from both.
+
+=over
+
+=item 1. Create a Schema object representing the database you are working with:
+
+ my $schema = MyDatabase::Schema->connect('dbi:SQLite:my.db');
+
+=item 2. Call the B<search> method on the resultset for the L<ResultSource|DBIx::Class::ResultSource> you wish to update data in, joining to the second table:
+
+ my $posts = $schema->resultset('Post')->search(
+ {},
+ { join => 'user' }
+ );
+
+ The B<join> key takes as an argument a nested structure of one or more relation names (see L<DBIx::Class::Manual::SQLHackers::CREATE>).
+
+=item 3. Call the B<update> method on the resultset to run the UPDATE statement:
+
+ $posts->update({ 'me.title' => \[ 'user.username || me.title' ] });
+
+^^ I am 95% sure this won't actually work, please try it (ideally as a passing or failing test)
+
+=back
projects / dbsrgits/DBIx-Class-Manual-SQLHackers.git / commitdiff