add placeholder support detection for mssql through dbd::sybase

diff --git a/lib/DBIx/Class/Storage/DBI/Sybase/Microsoft_SQL_Server.pm b/lib/DBIx/Class/Storage/DBI/Sybase/Microsoft_SQL_Server.pm
index 27cda34..dfbe20b 100644 (file)
--- a/lib/DBIx/Class/Storage/DBI/Sybase/Microsoft_SQL_Server.pm
+++ b/lib/DBIx/Class/Storage/DBI/Sybase/Microsoft_SQL_Server.pm
@@ -9,6 +9,32 @@ use base qw/
 /;
 use mro 'c3';
 
+sub _rebless {
+  my $self = shift;
+  my $dbh  = $self->_dbh;
+
+  my ($placeholders_supported) = eval {
+# There's also $dbh->{syb_dynamic_supported} but it can be inaccurate for this
+# purpose.
+    local $dbh->{PrintError} = 0;
+    $dbh->selectrow_array('select ?', {}, 1);
+  };
+
+  if (not $placeholders_supported) {
+    bless $self,
+      'DBIx::Class::Storage::DBI::Sybase::Microsoft_SQL_Server::NoBindVars';
+    $self->_rebless;
+  }
+
+# LongReadLen doesn't work with MSSQL through DBD::Sybase, and the default is
+# huge on some versions of SQL server and can cause memory problems, so we
+# fix it up here.
+  my $text_size = eval { $self->_dbi_connect_info->[-1]->{LongReadLen} } ||
+    32768; # the DBD::Sybase default
+
+  $dbh->do("set textsize $text_size");
+}
+
 1;
 
 =head1 NAME
@@ -20,14 +46,15 @@ SQL Server via DBD::Sybase
 
 This subclass supports MSSQL server connections via L<DBD::Sybase>.
 
-=head1 CAVEATS
+=head1 DESCRIPTION
 
-This storage driver uses L<DBIx::Class::Storage::DBI::NoBindVars> as a base.
-This means that bind variables will be interpolated (properly quoted of course)
-into the SQL query itself, without using bind placeholders.
+This driver tries to determine whether your version of L<DBD::Sybase> and
+supporting libraries (usually FreeTDS) support using placeholders, if not the
+storage will be reblessed to
+L<DBIx::Class::Storage::DBI::Sybase::Microsoft_SQL_Server::NoBindVars>.
 
-More importantly this means that caching of prepared statements is explicitly
-disabled, as the interpolation renders it useless.
+The MSSQL specific functionality is provided by
+L<DBIx::Class::Storage::DBI::MSSQL>.
 
 =head1 AUTHOR
 

diff --git a/lib/DBIx/Class/Storage/DBI/Sybase/Microsoft_SQL_Server/NoBindVars.pm b/lib/DBIx/Class/Storage/DBI/Sybase/Microsoft_SQL_Server/NoBindVars.pm
new file mode 100644 (file)
index 0000000..16db6d1
--- /dev/null
+++ b/lib/DBIx/Class/Storage/DBI/Sybase/Microsoft_SQL_Server/NoBindVars.pm
@@ -0,0 +1,53 @@
+package DBIx::Class::Storage::DBI::Sybase::Microsoft_SQL_Server::NoBindVars;
+
+use strict;
+use warnings;
+
+use base qw/
+  DBIx::Class::Storage::DBI::NoBindVars
+  DBIx::Class::Storage::DBI::Sybase::Microsoft_SQL_Server
+/;
+use mro 'c3';
+
+sub _rebless {
+  my $self = shift;
+
+  $self->disable_sth_caching(1);
+}
+
+1;
+
+=head1 NAME
+
+DBIx::Class::Storage::DBI::Sybase::Microsoft_SQL_Server::NoBindVars - Support for Microsoft
+SQL Server via DBD::Sybase without placeholders
+
+=head1 SYNOPSIS
+
+This subclass supports MSSQL server connections via DBD::Sybase when ? style
+placeholders are not available.
+
+=head1 DESCRIPTION
+
+If you are using this driver then your combination of L<DBD::Sybase> and
+libraries (most likely FreeTDS) does not support ? style placeholders.
+
+This storage driver uses L<DBIx::Class::Storage::DBI::NoBindVars> as a base.
+This means that bind variables will be interpolated (properly quoted of course)
+into the SQL query itself, without using bind placeholders.
+
+More importantly this means that caching of prepared statements is explicitly
+disabled, as the interpolation renders it useless.
+
+In all other respects, it is a subclass of
+L<DBIx::Class::Storage::DBI::Sybase::Microsoft_SQL_Server>.
+
+=head1 AUTHOR
+
+See L<DBIx::Class/CONTRIBUTORS>.
+
+=head1 LICENSE
+
+You may distribute this code under the same terms as Perl itself.
+
+=cut

diff --git a/t/74mssql.t b/t/74mssql.t
index cbaffc0..55d599f 100644 (file)
--- a/t/74mssql.t
+++ b/t/74mssql.t
@@ -18,104 +18,128 @@ my ($dsn, $user, $pass) = @ENV{map { "DBICTEST_MSSQL_${_}" } qw/DSN USER PASS/};
 plan skip_all => 'Set $ENV{DBICTEST_MSSQL_DSN}, _USER and _PASS to run this test'
   unless ($dsn);
 
-plan tests => 13;
+my $TESTS = 13;
 
-my $schema = DBICTest::Schema->clone;
-$schema->connection($dsn, $user, $pass);
+plan tests => $TESTS * 2;
 
-# start disconnected to test reconnection
-$schema->storage->ensure_connected;
-$schema->storage->_dbh->disconnect;
+my @storage_types = (
+  'DBIx::Class::Storage::DBI::Sybase::Microsoft_SQL_Server',
+  'DBIx::Class::Storage::DBI::Sybase::Microsoft_SQL_Server::NoBindVars',
+);
+my $storage_idx = -1;
+my $schema;
+
+for my $storage_type (@storage_types) {
+  $storage_idx++;
 
-isa_ok($schema->storage, 'DBIx::Class::Storage::DBI::Sybase::Microsoft_SQL_Server');
+  $schema = DBICTest::Schema->clone;
+
+  if ($storage_idx != 0) { # autodetect
+    $schema->storage_type($storage_type);
+  }
 
-my $dbh;
-lives_ok (sub {
-  $dbh = $schema->storage->dbh;
-}, 'reconnect works');
+  $schema->connection($dsn, $user, $pass);
 
-$dbh->do("IF OBJECT_ID('artist', 'U') IS NOT NULL
-    DROP TABLE artist");
-$dbh->do("IF OBJECT_ID('cd', 'U') IS NOT NULL
-    DROP TABLE cd");
+  $schema->storage->ensure_connected;
 
-$dbh->do("CREATE TABLE artist (artistid INT IDENTITY PRIMARY KEY, name VARCHAR(100), rank INT DEFAULT '13', charfield CHAR(10) NULL);");
-$dbh->do("CREATE TABLE cd (cdid INT IDENTITY PRIMARY KEY, artist INT,  title VARCHAR(100), year VARCHAR(100), genreid INT NULL, single_track INT NULL);");
+  if ($storage_idx == 0 && ref($schema->storage) =~ /NoBindVars\z/) {
+    my $tb = Test::More->builder;
+    $tb->skip('no placeholders') for 1..$TESTS;
+    next;
+  }
+
+  isa_ok($schema->storage, $storage_type);
+
+# start disconnected to test reconnection
+  $schema->storage->_dbh->disconnect;
+
+  my $dbh;
+  lives_ok (sub {
+    $dbh = $schema->storage->dbh;
+  }, 'reconnect works');
+
+  $dbh->do("IF OBJECT_ID('artist', 'U') IS NOT NULL
+      DROP TABLE artist");
+  $dbh->do("IF OBJECT_ID('cd', 'U') IS NOT NULL
+      DROP TABLE cd");
+
+  $dbh->do("CREATE TABLE artist (artistid INT IDENTITY PRIMARY KEY, name VARCHAR(100), rank INT DEFAULT '13', charfield CHAR(10) NULL);");
+  $dbh->do("CREATE TABLE cd (cdid INT IDENTITY PRIMARY KEY, artist INT,  title VARCHAR(100), year VARCHAR(100), genreid INT NULL, single_track INT NULL);");
 # Just to test compat shim, Auto is in Core
-$schema->class('Artist')->load_components('PK::Auto::MSSQL');
+  $schema->class('Artist')->load_components('PK::Auto::MSSQL');
 
 # Test PK
-my $new = $schema->resultset('Artist')->create( { name => 'foo' } );
-ok($new->artistid, "Auto-PK worked");
+  my $new = $schema->resultset('Artist')->create( { name => 'foo' } );
+  ok($new->artistid, "Auto-PK worked");
 
 # Test LIMIT
-for (1..6) {
-    $schema->resultset('Artist')->create( { name => 'Artist ' . $_, rank => $_ } );
-}
+  for (1..6) {
+      $schema->resultset('Artist')->create( { name => 'Artist ' . $_, rank => $_ } );
+  }
 
-my $it = $schema->resultset('Artist')->search( { },
-    { rows     => 3,
-      offset   => 2,
-      order_by => 'artistid'
-    }
-);
+  my $it = $schema->resultset('Artist')->search( { },
+      { rows     => 3,
+        offset   => 2,
+        order_by => 'artistid'
+      }
+  );
 
 # Test ? in data don't get treated as placeholders
-my $cd = $schema->resultset('CD')->create( {
-    artist      => 1,
-    title       => 'Does this break things?',
-    year        => 2007,
-} );
-ok($cd->id, 'Not treating ? in data as placeholders');
-
-is( $it->count, 3, "LIMIT count ok" );
-ok( $it->next->name, "iterator->next ok" );
-$it->next;
-$it->next;
-is( $it->next, undef, "next past end of resultset ok" );
+  my $cd = $schema->resultset('CD')->create( {
+      artist      => 1,
+      title       => 'Does this break things?',
+      year        => 2007,
+  } );
+  ok($cd->id, 'Not treating ? in data as placeholders');
+
+  is( $it->count, 3, "LIMIT count ok" );
+  ok( $it->next->name, "iterator->next ok" );
+  $it->next;
+  $it->next;
+  is( $it->next, undef, "next past end of resultset ok" );
 
 # test MONEY column support
-$schema->storage->dbh_do (sub {
-    my ($storage, $dbh) = @_;
-    eval { $dbh->do("DROP TABLE money_test") };
-    $dbh->do(<<'SQL');
+  $schema->storage->dbh_do (sub {
+      my ($storage, $dbh) = @_;
+      eval { $dbh->do("DROP TABLE money_test") };
+      $dbh->do(<<'SQL');
 
-CREATE TABLE money_test (
-   id INT IDENTITY PRIMARY KEY,
-   amount MONEY NULL
-)
+  CREATE TABLE money_test (
+     id INT IDENTITY PRIMARY KEY,
+     amount MONEY NULL
+  )
 
 SQL
 
-});
+  });
 
-my $rs = $schema->resultset('Money');
+  my $rs = $schema->resultset('Money');
 
-my $row;
-lives_ok {
-  $row = $rs->create({ amount => 100 });
-} 'inserted a money value';
+  my $row;
+  lives_ok {
+    $row = $rs->create({ amount => 100 });
+  } 'inserted a money value';
 
-is $rs->find($row->id)->amount, 100, 'money value round-trip';
+  is $rs->find($row->id)->amount, 100, 'money value round-trip';
 
-lives_ok {
-  $row->update({ amount => 200 });
-} 'updated a money value';
+  lives_ok {
+    $row->update({ amount => 200 });
+  } 'updated a money value';
 
-is $rs->find($row->id)->amount, 200, 'updated money value round-trip';
+  is $rs->find($row->id)->amount, 200, 'updated money value round-trip';
 
-lives_ok {
-  $row->update({ amount => undef });
-} 'updated a money value to NULL';
+  lives_ok {
+    $row->update({ amount => undef });
+  } 'updated a money value to NULL';
 
-is $rs->find($row->id)->amount, undef,'updated money value to NULL round-trip';
+  is $rs->find($row->id)->amount, undef,'updated money value to NULL round-trip';
+}
 
 # clean up our mess
 END {
-    $dbh->do("IF OBJECT_ID('artist', 'U') IS NOT NULL DROP TABLE artist")
-        if $dbh;
-    $dbh->do("IF OBJECT_ID('cd', 'U') IS NOT NULL DROP TABLE cd")
-        if $dbh;
-    $dbh->do("IF OBJECT_ID('money_test', 'U') IS NOT NULL DROP TABLE money_test")
-        if $dbh;
+  if (my $dbh = eval { $schema->storage->dbh }) {
+    $dbh->do("IF OBJECT_ID('artist', 'U') IS NOT NULL DROP TABLE artist");
+    $dbh->do("IF OBJECT_ID('cd', 'U') IS NOT NULL DROP TABLE cd");
+    $dbh->do("IF OBJECT_ID('money_test', 'U') IS NOT NULL DROP TABLE money_test");
+  }
 }