add lookup plugin.

MANIFEST

@@ -14,6 +14,7 @@ lib/Teng/Iterator.pm
 lib/Teng/Plugin/BulkInsert.pm
 lib/Teng/Plugin/Count.pm
 lib/Teng/Plugin/FindOrCreate.pm
+lib/Teng/Plugin/Lookup.pm
 lib/Teng/Plugin/Pager.pm
 lib/Teng/Plugin/Pager/MySQLFoundRows.pm
 lib/Teng/Plugin/Replace.pm
@@ -44,6 +45,8 @@ t/001_basic/023_bulk_insert.t
 t/001_basic/024_bind_column.t
 t/001_basic/025_pager.t
 t/001_basic/026_fork.t
+t/001_basic/027_fork_self_reconnect.t
+t/001_basic/028_lookup.t
 t/002_common/000_new.t
 t/002_common/001_insert.t
 t/002_common/002_update.t
@@ -71,6 +74,7 @@ t/999_regression/guess_table_name.t
 t/999_regression/inflate_bug.t
 t/999_regression/no_schema.t
 t/999_regression/prepare_error_handling.t
+t/999_regression/reconnect.t
 t/lib/Mock/Basic.pm
 t/lib/Mock/Basic/Schema.pm
 t/lib/Mock/BasicBindColumn.pm

lib/Teng/Plugin/Lookup.pm

@@ -0,0 +1,71 @@
+package Teng::Plugin::Lookup;
+use strict;
+use warnings;
+use utf8;
+
+our @EXPORT = qw/lookup/;
+
+sub lookup {
+    my ($self, $table_name, $where, $opt) = @_;
+
+    my $table = $self->{schema}->get_table( $table_name );
+    Carp::croak("No such table $table_name") unless $table;
+
+    my $cond = join ' AND', map {"$_ = ?"} keys %$where;
+    my $sql = sprintf('SELECT %s FROM %s WHERE %s %s',
+               join(',', @{$table->{columns}}),
+               $table_name,
+               $cond,
+               $opt->{for_update} ? 'FOR UPDATE' : '',
+           );
+
+    my $sth = $self->_execute($sql, [values %$where]);
+    my $row = $sth->fetchrow_hashref('NAME_lc');
+
+    return unless $row;
+    return $row if $self->{suppress_row_objects};
+
+    $table->{row_class}->new(
+        {
+            sql        => $sql,
+            row_data   => $row,
+            teng       => $self,
+            table      => $table,
+            table_name => $table_name,
+        }
+    );
+}
+
+1;
+__END__
+
+=head1 NAME
+
+Teng::Plugin::Lookup - lookup single row.
+
+=head1 NAME
+
+    package MyDB;
+    use parent qw/Teng/;
+    __PACKAGE__->load_plugin('Lookup');
+
+    package main;
+    my $db = MyDB->new(...);
+    $db->lookup('user' => +{id => 1}); # => get single row
+
+=head1 DESCRIPTION
+
+This plugin provides fast lookup row .
+
+=head1 METHODS
+
+=over 4
+
+=item $row = $db->lookup($table_name, \%search_condition, [\%attr]);
+
+lookup single row records.
+
+Teng#single is heavy.
+
+=back
+

t/001_basic/028_lookup.t

@@ -0,0 +1,26 @@
+use t::Utils;
+use Mock::Basic;
+use Test::More;
+
+my $dbh = t::Utils->setup_dbh;
+my $db_basic = Mock::Basic->new({dbh => $dbh});
+$db_basic->setup_test_db;
+Mock::Basic->load_plugin('Lookup');
+
+subtest 'bulk_insert method' => sub {
+    $db_basic->insert('mock_basic', => +{
+        id   => 1,
+        name => 'perl',
+    });
+
+    my $row = $db_basic->lookup('mock_basic', +{id => 1});
+    isa_ok $row, 'Mock::Basic::Row::MockBasic';
+    is_deeply $row->get_columns, +{
+        id        => 1,
+        name      => 'perl',
+        delete_fg => 0,
+    };
+};
+
+done_testing;
+