append half of a base64 MD5 to shortened table aliases for Oracle

[dbsrgits/DBIx-Class.git] / lib / DBIx / Class / Storage / DBI / Oracle / Generic.pm

diff --git a/lib/DBIx/Class/Storage/DBI/Oracle/Generic.pm b/lib/DBIx/Class/Storage/DBI/Oracle/Generic.pm
index b1f3ddf..5ed31a0 100644 (file)
--- a/lib/DBIx/Class/Storage/DBI/Oracle/Generic.pm
+++ b/lib/DBIx/Class/Storage/DBI/Oracle/Generic.pm
@@ -9,15 +9,17 @@ DBIx::Class::Storage::DBI::Oracle::Generic - Oracle Support for DBIx::Class
 
 =head1 SYNOPSIS
 
-  # In your table classes
-  __PACKAGE__->load_components(qw/PK::Auto Core/);
+  # In your result (table) classes
+  use base 'DBIx::Class::Core';
   __PACKAGE__->add_columns({ id => { sequence => 'mysequence', auto_nextval => 1 } });
   __PACKAGE__->set_primary_key('id');
   __PACKAGE__->sequence('mysequence');
 
 =head1 DESCRIPTION
 
-This class implements autoincrements for Oracle.
+This class implements base Oracle support. The subclass
+L<DBIx::Class::Storage::DBI::Oracle::WhereJoins> is for C<(+)> joins in Oracle
+versions before 9.
 
 =head1 METHODS
 
@@ -274,6 +276,40 @@ sub _svp_rollback {
     $self->_get_dbh->do("ROLLBACK TO SAVEPOINT $name")
 }
 
+=head2 relname_to_table_alias
+
+L<DBIx::Class> uses L<DBIx::Class::Relationship> names as table aliases in
+queries.
+
+Unfortunately, Oracle doesn't support identifiers over 30 chars in length, so
+the L<DBIx::Class::Relationship> name is shortened and appended with half of an
+MD5 hash.
+
+See L<DBIx::Class::Storage/"relname_to_table_alias">.
+
+=cut
+
+sub relname_to_table_alias {
+  my $self = shift;
+  my ($relname, $join_count) = @_;
+
+  my $alias = $self->next::method(@_);
+
+  return $alias if length($alias) <= 30;
+
+  # get a base64 md5 of the alias with join_count
+  require Digest::MD5;
+  my $ctx = Digest::MD5->new;
+  $ctx->add($alias);
+  my $md5 = $ctx->b64digest;
+
+  # truncate and prepend to truncated relname without vowels
+  (my $devoweled = $relname) =~ s/[aeiou]//g;
+  my $res = substr($devoweled, 0, 18) . '_' . substr($md5, 0, 11);
+
+  return $res;
+}
+
 =head1 AUTHOR
 
 See L<DBIx::Class/CONTRIBUTORS>.