add OffsetFetch support

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

diff --git a/lib/DBIx/Class/Storage/DBI/MSSQL.pm b/lib/DBIx/Class/Storage/DBI/MSSQL.pm
index 34d3745..bbeaeef 100644 (file)
--- a/lib/DBIx/Class/Storage/DBI/MSSQL.pm
+++ b/lib/DBIx/Class/Storage/DBI/MSSQL.pm
@@ -27,6 +27,25 @@ __PACKAGE__->datetime_parser_type (
 
 __PACKAGE__->new_guid('NEWID()');
 
+sub __sql_server_x_or_higher {
+  my ($self, $version) = @_;
+
+  if (exists $_[0]->_server_info->{normalized_dbms_version}) {
+    if ($_[0]->_server_info->{normalized_dbms_version} >= $version) {
+       return 1
+    } else {
+       return 0
+    }
+  }
+  return undef;
+}
+
+sub __offset_bindtype { +{ dbd_attrs => DBI::SQL_INTEGER() } }
+sub __rows_bindtype   { +{ dbd_attrs => DBI::SQL_INTEGER() } }
+
+sub _sql_server_2005_or_higher { shift->__sql_server_x_or_higher(9) }
+sub _sql_server_2012_or_higher { shift->__sql_server_x_or_higher(11) }
+
 sub _prep_for_execute {
   my $self = shift;
   my ($op, $ident, $args) = @_;
@@ -151,12 +170,23 @@ sub sqlt_type { 'SQLServer' }
 sub sql_limit_dialect {
   my $self = shift;
 
-  my $supports_rno = 0;
+  my $supports_ofn = $self->_sql_server_2012_or_higher;
 
-  if (exists $self->_server_info->{normalized_dbms_version}) {
-    $supports_rno = 1 if $self->_server_info->{normalized_dbms_version} >= 9;
+  unless (defined $supports_ofn) {
+    # User is connecting via DBD::Sybase and has no permission to run
+    # stored procedures like xp_msver, or version detection failed for some
+    # other reason.
+    # So, we use a query to check if OFN is implemented.
+    try {
+      $self->_get_dbh->selectrow_array('SELECT 1 ORDER BY 1 OFFSET 0 ROWS');
+      $supports_ofn = 1;
+    };
   }
-  else {
+  return 'OffsetFetchNext' if $supports_ofn;
+
+  my $supports_rno = $self->_sql_server_2005_or_higher;
+
+  unless (defined $supports_rno) {
     # User is connecting via DBD::Sybase and has no permission to run
     # stored procedures like xp_msver, or version detection failed for some
     # other reason.
@@ -166,8 +196,9 @@ sub sql_limit_dialect {
       $supports_rno = 1;
     };
   }
+  return 'RowNumberOver' if $supports_rno;
 
-  return $supports_rno ? 'RowNumberOver' : 'Top';
+  return 'Top';
 }
 
 sub _ping {