+ $self->scalar_sql($sql, @_);
+}
+
+=item row_exists [ WHERE [, PLACEHOLDER ...] ]
+
+Convenience method for the common case of "SELECT 1 FROM table ... LIMIT 1"
+with optional (but almost always needed) WHERE.
+
+=cut
+
+sub row_exists {
+ my($self, $where) = (shift, shift);
+ my $table = $self->table or die 'row_exists called on object of class '.ref($self);
+ my $sql = "SELECT 1 FROM $table";
+ $sql .= " WHERE $where" if $where;
+ $sql .= " LIMIT 1";
+ $self->scalar_sql($sql, @_);