Rewrite selector using sqla

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

diff --git a/lib/DBIx/Class/Storage/DBI/Pg.pm b/lib/DBIx/Class/Storage/DBI/Pg.pm
index 0818aa7..1348d33 100644 (file)
--- a/lib/DBIx/Class/Storage/DBI/Pg.pm
+++ b/lib/DBIx/Class/Storage/DBI/Pg.pm
@@ -39,6 +39,7 @@ sub _dbh_last_insert_id {
 }
 
 
+# get the postgres search path, and cache it
 sub _get_pg_search_path {
     my ($self,$dbh) = @_;
     # cache the search path as ['schema','schema',...] in the storage
@@ -59,72 +60,38 @@ sub _get_pg_search_path {
 sub _dbh_get_autoinc_seq {
   my ($self, $dbh, $schema, $table, $col) = @_;
 
-  # get the list of postgres schemas to search.  if we have a schema
-  # specified, use that.  otherwise, use the search path
-  my @search_path;
-  if( defined $schema and length $schema ) {
-      @search_path = ( $schema );
-  } else {
-      @search_path = @{ $self->_get_pg_search_path($dbh) };
+  my $sqlmaker = $self->sql_maker;
+  local $sqlmaker->{bindtype} = 'normal';
+
+  my ($where, @bind) = $self->sql_maker->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) = $dbh->selectrow_array(<<EOS,undef,@bind);
+
+SELECT
+  (SELECT pg_catalog.pg_get_expr(d.adbin, d.adrelid)
+   FROM pg_catalog.pg_attrdef d
+   WHERE d.adrelid = a.attrelid AND d.adnum = a.attnum AND a.atthasdef)
+FROM pg_catalog.pg_class c
+     JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
+     JOIN pg_catalog.pg_attribute a ON a.attrelid = c.oid
+$where
+
+EOS
+
+  unless (defined $seq_expr && $seq_expr =~ /^nextval\(+'([^']+)'::(?:text|regclass)\)/i ){
+    $seq_expr = '' unless defined $seq_expr;
+    $self->throw_exception("could not parse sequence expression: '$seq_expr'");
   }
 
-  # find the sequence(s) of the column in question (should have nextval declared on it)
-  my @sequence_names;
-  foreach my $search_schema (@search_path) {
-    my $info = $dbh->column_info(undef,$search_schema,$table,$col)->fetchrow_hashref;
-    if($info && defined $info->{COLUMN_DEF}
-             && $info->{COLUMN_DEF} =~ /^nextval\(+'([^']+)'::(?:text|regclass)\)/i
-    ) {
-        push @sequence_names, $1;
-    }
-  }
-
-  if (@sequence_names != 1) {
-    $self->throw_exception (sprintf
-      q|Unable to reliably determine autoinc sequence name for '%s'.'%s' (possible candidates: %s)|,
-      $table,
-      $col,
-      join (', ', (@sequence_names ? @sequence_names : 'none found') ),
-    );
-  }
-
-  my $seq = $sequence_names[0];
-
-  if( $seq !~ /\./ ) {
-    my $sth = $dbh->prepare (
-      'SELECT * FROM "information_schema"."sequences" WHERE "sequence_name" = ?'
-    );
-    $sth->execute ($seq);
-
-    my @seen_in_schemas;
-    while (my $h = $sth->fetchrow_hashref) {
-      push @seen_in_schemas, $h->{sequence_schema};
-    }
-
-    if (not @seen_in_schemas) {
-      $self->throw_exception (sprintf
-        q|Automatically determined autoinc sequence name '%s' for '%s'.'%s' does not seem to exist...'|,
-        $seq,
-        $table,
-        $col,
-      );
-    }
-    elsif (@seen_in_schemas > 1) {
-      $self->throw_exception (sprintf
-        q|Unable to reliably fully-qualify automatically determined autoinc sequence name '%s' for '%s'.'%s' (same name exist in schemas: %s)|,
-        $seq,
-        $table,
-        $col,
-        join (', ', (@seen_in_schemas)),
-      );
-    }
-    else {
-      my $sql_maker = $self->sql_maker;
-      $seq = join ('.', map { $sql_maker->_quote ($_) } ($seen_in_schemas[0], $seq) );
-    }
-  }
-
-  return $seq;
+  return $1;
 }
 
 sub get_autoinc_seq {
@@ -191,6 +158,8 @@ sub _svp_rollback {
 
 1;
 
+__END__
+
 =head1 NAME
 
 DBIx::Class::Storage::DBI::Pg - Automatic primary key class for PostgreSQL
@@ -208,13 +177,17 @@ This class implements autoincrements for PostgreSQL.
 
 =head1 POSTGRESQL SCHEMA SUPPORT
 
-This supports multiple PostgreSQL schemas, with one caveat: for
-performance reasons, the schema search path is queried the first time it is
-needed and CACHED for subsequent uses.
+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.
 
-For this reason, you should do any necessary manipulation of the
-PostgreSQL search path BEFORE instantiating your schema object, or as
-part of the on_connect_do option to connect(), for example:
+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,