X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass%2FStorage%2FDBI%2FPg.pm;h=1444cfef1a3b0fe0857dd1be50440ff838932422;hb=734868da8acee7ff14dff8b91ab18f0edc3c10df;hp=ac24ad364813f2ff5e4b250dedab5bff13f38f0e;hpb=7f32c82b6791c30615bd6da46063e2a80be3ebc5;p=dbsrgits%2FDBIx-Class.git

diff --git a/lib/DBIx/Class/Storage/DBI/Pg.pm b/lib/DBIx/Class/Storage/DBI/Pg.pm
index ac24ad3..1444cfe 100644
--- a/lib/DBIx/Class/Storage/DBI/Pg.pm
+++ b/lib/DBIx/Class/Storage/DBI/Pg.pm
@@ -3,61 +3,158 @@ package DBIx::Class::Storage::DBI::Pg;
 use strict;
 use warnings;
 
-use base qw/DBIx::Class::Storage::DBI::MultiColumnIn/;
+use base qw/
+    DBIx::Class::Storage::DBI::MultiColumnIn
+/;
 use mro 'c3';
 
 use DBD::Pg qw(:pg_types);
+use Scope::Guard ();
+use Context::Preserve ();
 
 # Ask for a DBD::Pg with array support
-warn "DBD::Pg 2.9.2 or greater is strongly recommended\n"
+warn __PACKAGE__.": DBD::Pg 2.9.2 or greater is strongly recommended\n"
   if ($DBD::Pg::VERSION < 2.009002);  # pg uses (used?) version::qv()
 
+sub can_insert_returning {
+  # FIXME !!!
+  # pg before 8.2 doesn't support this, need to check version
+  return 1;
+}
+
 sub with_deferred_fk_checks {
   my ($self, $sub) = @_;
 
-  $self->_get_dbh->do('SET CONSTRAINTS ALL DEFERRED');
-  $sub->();
-}
+  my $txn_scope_guard = $self->txn_scope_guard;
+
+  $self->_do_query('SET CONSTRAINTS ALL DEFERRED');
 
-sub _dbh_last_insert_id {
-  my ($self, $dbh, $seq) = @_;
-  $dbh->last_insert_id(undef, undef, undef, undef, {sequence => $seq});
+  my $sg = Scope::Guard->new(sub {
+    $self->_do_query('SET CONSTRAINTS ALL IMMEDIATE');
+  });
+
+  return Context::Preserve::preserve_context(sub { $sub->() },
+    after => sub { $txn_scope_guard->commit });
 }
 
 sub last_insert_id {
-  my ($self,$source,$col) = @_;
-  my $seq = ($source->column_info($col)->{sequence} ||= $self->get_autoinc_seq($source,$col));
-  $self->throw_exception("could not fetch primary key for " . $source->name . ", could not "
-    . "get autoinc sequence for $col (check that table and column specifications are correct "
-    . "and in the correct case)") unless defined $seq;
-  $self->dbh_do('_dbh_last_insert_id', $seq);
+  my ($self,$source,@cols) = @_;
+
+  my @values;
+
+  for my $col (@cols) {
+    my $seq = ( $source->column_info($col)->{sequence} ||= $self->dbh_do('_dbh_get_autoinc_seq', $source, $col) )
+      or $self->throw_exception( sprintf(
+        'could not determine sequence for column %s.%s, please consider adding a schema-qualified sequence to its column info',
+          $source->name,
+          $col,
+      ));
+
+    push @values, $self->_dbh->last_insert_id(undef, undef, undef, undef, {sequence => $seq});
+  }
+
+  return @values;
+}
+
+sub _sequence_fetch {
+  my ($self, $function, $sequence) = @_;
+
+  $self->throw_exception('No sequence to fetch') unless $sequence;
+
+  my ($val) = $self->_get_dbh->selectrow_array(
+    sprintf ("select %s('%s')", $function, $sequence)
+  );
+
+  return $val;
 }
 
 sub _dbh_get_autoinc_seq {
-  my ($self, $dbh, $schema, $table, @pri) = @_;
-
-  while (my $col = shift @pri) {
-    my $info = $dbh->column_info(undef,$schema,$table,$col)->fetchrow_hashref;
-    if(defined $info->{COLUMN_DEF} and
-       $info->{COLUMN_DEF} =~ /^nextval\(+'([^']+)'::(?:text|regclass)\)/) {
-      my $seq = $1;
-      # may need to strip quotes -- see if this works
-      return $seq =~ /\./ ? $seq : $info->{TABLE_SCHEM} . "." . $seq;
-    }
+  my ($self, $dbh, $source, $col) = @_;
+
+  my $schema;
+  my $table = $source->name;
+
+  # deref table name if it needs it
+  $table = $$table
+      if ref $table eq 'SCALAR';
+
+  # parse out schema name if present
+  if( $table =~ /^(.+)\.(.+)$/ ) {
+    ( $schema, $table ) = ( $1, $2 );
   }
-  return;
-}
 
-sub get_autoinc_seq {
-  my ($self,$source,$col) = @_;
+  # get the column default using a Postgres-specific pg_catalog query
+  my $seq_expr = $self->_dbh_get_column_default( $dbh, $schema, $table, $col );
+
+  # if no default value is set on the column, or if we can't parse the
+  # default value as a sequence, throw.
+  unless ( defined $seq_expr and $seq_expr =~ /^nextval\(+'([^']+)'::(?:text|regclass)\)/i ) {
+    $seq_expr = '' unless defined $seq_expr;
+    $schema = "$schema." if defined $schema && length $schema;
+    $self->throw_exception( sprintf (
+      'no sequence found for %s%s.%s, check the RDBMS table definition or explicitly set the '.
+      "'sequence' for this column in %s",
+        $schema ? "$schema." : '',
+        $table,
+        $col,
+        $source->source_name,
+    ));
+  }
 
-  my @pri = $source->primary_columns;
-  my ($schema,$table) = $source->name =~ /^(.+)\.(.+)$/ ? ($1,$2)
-    : (undef,$source->name);
+  return $1;
+}
 
-  $self->dbh_do('_dbh_get_autoinc_seq', $schema, $table, @pri);
+# custom method for fetching column default, since column_info has a
+# bug with older versions of DBD::Pg
+sub _dbh_get_column_default {
+  my ( $self, $dbh, $schema, $table, $col ) = @_;
+
+  # Build and execute a query into the pg_catalog to find the Pg
+  # expression for the default value for this column in this table.
+  # If the table name is schema-qualified, query using that specific
+  # schema name.
+
+  # Otherwise, find the table in the standard Postgres way, using the
+  # search path.  This is done with the pg_catalog.pg_table_is_visible
+  # function, which returns true if a given table is 'visible',
+  # meaning the first table of that name to be found in the search
+  # path.
+
+  # I *think* we can be assured that this query will always find the
+  # correct column according to standard Postgres semantics.
+  #
+  # -- rbuels
+
+  my $sqlmaker = $self->sql_maker;
+  local $sqlmaker->{bindtype} = 'normal';
+
+  my ($where, @bind) = $sqlmaker->where ({
+    'a.attnum' => {'>', 0},
+    'c.relname' => $table,
+    'a.attname' => $col,
+    -not_bool => 'a.attisdropped',
+    (defined $schema && length $schema)
+      ? ( 'n.nspname' => $schema )
+      : ( -bool => \'pg_catalog.pg_table_is_visible(c.oid)' )
+  });
+
+  my ($seq_expr) = $dbh->selectrow_array(<<EOS,undef,@bind);
+
+SELECT
+  (SELECT pg_catalog.pg_get_expr(d.adbin, d.adrelid)
+   FROM pg_catalog.pg_attrdef d
+   WHERE d.adrelid = a.attrelid AND d.adnum = a.attnum AND a.atthasdef)
+FROM pg_catalog.pg_class c
+     LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
+     JOIN pg_catalog.pg_attribute a ON a.attrelid = c.oid
+$where
+
+EOS
+
+  return $seq_expr;
 }
 
+
 sub sqlt_type {
   return 'PostgreSQL';
 }
@@ -80,12 +177,6 @@ sub bind_attribute_by_data_type {
   }
 }
 
-sub _sequence_fetch {
-  my ( $self, $type, $seq ) = @_;
-  my ($id) = $self->_get_dbh->selectrow_array("SELECT nextval('${seq}')");
-  return $id;
-}
-
 sub _svp_begin {
     my ($self, $name) = @_;
 
@@ -106,14 +197,16 @@ sub _svp_rollback {
 
 1;
 
+__END__
+
 =head1 NAME
 
 DBIx::Class::Storage::DBI::Pg - Automatic primary key class for PostgreSQL
 
 =head1 SYNOPSIS
 
-  # In your table classes
-  __PACKAGE__->load_components(qw/PK::Auto Core/);
+  # In your result (table) classes
+  use base 'DBIx::Class::Core';
   __PACKAGE__->set_primary_key('id');
   __PACKAGE__->sequence('mysequence');
 
@@ -121,9 +214,30 @@ DBIx::Class::Storage::DBI::Pg - Automatic primary key class for PostgreSQL
 
 This class implements autoincrements for PostgreSQL.
 
+=head1 POSTGRESQL SCHEMA SUPPORT
+
+This driver supports multiple PostgreSQL schemas, with one caveat: for
+performance reasons, data about the search path, sequence names, and
+so forth is queried as needed and CACHED for subsequent uses.
+
+For this reason, once your schema is instantiated, you should not
+change the PostgreSQL schema search path for that schema's database
+connection. If you do, Bad Things may happen.
+
+You should do any necessary manipulation of the search path BEFORE
+instantiating your schema object, or as part of the on_connect_do
+option to connect(), for example:
+
+   my $schema = My::Schema->connect
+                  ( $dsn,$user,$pass,
+                    { on_connect_do =>
+                        [ 'SET search_path TO myschema, foo, public' ],
+                    },
+                  );
+
 =head1 AUTHORS
 
-Marcus Ramberg <m.ramberg@cpan.org>
+See L<DBIx::Class/CONTRIBUTORS>
 
 =head1 LICENSE