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Teng - very simple DBI wrapper/ORMapper


    my $db = MyDB->new({ connect_info => [ 'dbi:SQLite:' ] });
    my $row = $db->insert( 'table' => {
        col1 => $value
    } );


Teng is very simple DBI wrapper and simple O/R Mapper. It aims to be lightweight, with minimal dependencies so it's easier to install.


create your db model base class.

    package Your::Model;
    use parent 'Teng';

create your db schema class. See Teng::Schema for docs on defining schema class.

    package Your::Model::Schema;
    use Teng::Schema::Declare;
    table {
        name 'user';
        pk 'id';
        columns qw( foo bar baz );

in your script.

    use Your::Model;
    my $teng = Your::Model->new(\%args);
    # insert new record.
    my $row = $teng->insert('user',
            id   => 1,
    $row->update({name => 'nekokak'}); # same do { $row->name('nekokak'); $row->update; }

    $row = $teng->single_by_sql(q{SELECT id, name FROM user WHERE id = ?}, [ 1 ]);


Teng classes are comprised of three distinct components:


The model is where you say

    package MyApp::Model;
    use parent 'Teng';

This is the entry point to using Teng. You connect, insert, update, delete, select stuff using this object.


The schema is a simple class that describes your table definitions. Note that this is different from DBIx::Class terms. DBIC's schema is equivalent to Teng's model + schema, where the actual schema information is scattered across the result classes.

In Teng, you simply use Teng::Schema's domain specific language to define a set of tables

    package MyApp::Model::Schema;
    use Teng::Schema::Declare;

    table {
        name $table_name;
        pk $primary_key_column;
        columns qw(

    ... and other tables ...


Unlike DBIx::Class, you don't need to have a set of classes that represent a row type (i.e. "result" classes in DBIC terms). In Teng, the row objects are blessed into anonymous classes that inherit from Teng::Row, so you don't have to create these classes if you just want to use some simple queries.

If you want to define methods to be performed by your row objects, simply create a row class like so:

    package MyApp::Model::Row::Camelizedtable_name;
    use parent qw(Teng::Row);

Note that your table name will be camelized.


Teng provides a number of methods to all your classes,

$teng = Teng->new(\%args)

Creates a new Teng instance.

    # connect new database connection.
    my $db = Your::Model->new(
        connect_info => [ $dsn, $username, $password, \%connect_options ]

Arguments can be:

  • connect_info

    Specifies the information required to connect to the database. The argument should be a reference to a array in the form:

        [ $dsn, $user, $password, \%options ]

    You must pass connect_info or dbh to the constructor.

  • dbh

    Specifies the database handle to use.

  • no_ping

    By default, ping before each executing query. If it affect performance then you can set to true for ping stopping.

  • fields_case

    specific's FetchHashKeyName.

  • schema

    Specifies the Teng::Schema instance to use. If not specified, the value specified in schema_class is loaded and instantiated for you.

  • schema_class

    Specifies the schema class to use. By default {YOUR_MODEL_CLASS}::Schema is used.

  • txn_manager_class

    Specifies the transaction manager class. By default DBIx::TransactionManager is used.

  • suppress_row_objects

    Specifies the row object creation mode. By default this value is false. If you specifies this to a true value, no row object will be created when a SELECT statement is issued..

  • force_deflate_set_column

    Specifies set_column, set_columns and column name method behaviour. By default this value is false. If you specifies this to a true value, set_column or column name method will deflate argument.

  • sql_builder

    Speficies the SQL builder object. By default SQL::Maker is used, and as such, if you provide your own SQL builder the interface needs to be compatible with SQL::Maker.

  • sql_builder_class : Str

    Speficies the SQL builder class name. By default SQL::Maker is used, and as such, if you provide your own SQL builder the interface needs to be compatible with SQL::Maker.

    Specified sql_builder_class is instantiated with following:

            driver => $teng->{driver_name},
            %{ $teng->{sql_builder_args}  }

    This is not used when sql_builder is specified.

  • sql_builder_args : HashRef

    Speficies the arguments for constructor of sql_builder_class. This is not used when sql_builder is specified.

  • trace_ignore_if : CodeRef

    Ignore to inject the SQL comment when trace_ignore_if's return value is true.

$row = $teng->insert($table_name, \%row_data)

Inserts a new record. Returns the inserted row object.

    my $row = $teng->insert('user',{
        id   => 1,
        name => 'nekokak',

If a primary key is available, it will be fetched after the insert -- so an INSERT followed by SELECT is performed. If you do not want this, use fast_insert.

$last_insert_id = $teng->fast_insert($table_name, \%row_data);

insert new record and get last_insert_id.

no creation row object.


Internal method called from insert and fast_insert. You can hook it on your responsibility.

$teng->bulk_insert($table_name, \@rows_data, \%opt)

Accepts either an arrayref of hashrefs. each hashref should be a structure suitable for submitting to a Your::Model->insert(...) method. The second argument is an arrayref of hashrefs. All of the keys in these hashrefs must be exactly the same.

insert many record by bulk.


            id   => 1,
            name => 'nekokak',
            id   => 2,
            name => 'yappo',
            id   => 3,
            name => 'walf443',

You can specify $opt like { prefix => 'INSERT IGNORE INTO' } or { update => { name => 'updated' } } optionally, which will be passed to query builder.

$update_row_count = $teng->update($table_name, \%update_row_data, [\%update_condition])

Calls UPDATE on $table_name, with values specified in %update_ro_data, and returns the number of rows updated. You may optionally specify %update_condition to create a conditional update query.

    my $update_row_count = $teng->update('user',
            name => 'nomaneko',
            id => 1
    # Executes UPDATE user SET name = 'nomaneko' WHERE id = 1

You can also call update on a row object:

    my $row = $teng->single('user',{id => 1});
    $row->update({name => 'nomaneko'});

You can use the set_column method:

    my $row = $teng->single('user', {id => 1});
    $row->set_column( name => 'yappo' );

you can column update by using column method:

    my $row = $teng->single('user', {id => 1});
$updated_row_count = $teng->do_update($table_name, \%set, \%where)

This is low level API for UPDATE. Normally, you should use update method instead of this.

This method does not deflate \%args.

$delete_row_count = $teng->delete($table, \%delete_condition)

Deletes the specified record(s) from $table and returns the number of rows deleted. You may optionally specify %delete_condition to create a conditional delete query.

    my $rows_deleted = $teng->delete( 'user', {
        id => 1
    } );
    # Executes DELETE FROM user WHERE id = 1

You can also call delete on a row object:

    my $row = $teng->single('user', {id => 1});
$itr = $teng->search($table_name, [\%search_condition, [\%search_attr]])

simple search method. search method get Teng::Iterator's instance object.

see Teng::Iterator

get iterator:

    my $itr = $teng->search('user',{id => 1},{order_by => 'id'});

get rows:

    my @rows = $teng->search('user',{id => 1},{order_by => 'id'});
$row = $teng->single($table_name, \%search_condition)

get one record. give back one case of the beginning when it is acquired plural records by single method.

    my $row = $teng->single('user',{id =>1});
$row = $teng->new_row_from_hash($table_name, \%row_data, [$sql])

create row object from data. (not fetch from db.) It's useful in such as testing.

    my $row = $teng->new_row_from_hash('user', { id => 1, foo => "bar" });
    say $row->foo; # say bar
$itr = $teng->search_named($sql, [\%bind_values, [$table_name]])

execute named query

    my $itr = $teng->search_named(q{SELECT * FROM user WHERE id = :id}, {id => 1});

If you give ArrayRef to value, that is expanded to "(?,?,?,?)" in SQL. It's useful in case use IN statement.

    # SELECT * FROM user WHERE id IN (?,?,?);
    # bind [1,2,3]
    my $itr = $teng->search_named(q{SELECT * FROM user WHERE id IN :ids}, {ids => [1, 2, 3]});

If you give table_name. It is assumed the hint that makes Teng::Row's Object.

$itr = $teng->search_by_sql($sql, [\@bind_values, [$table_name]])

execute your SQL

    my $itr = $teng->search_by_sql(q{
            id, name
            id = ?
    },[ 1 ]);

If $table is specified, it set table information to result iterator. So, you can use table row class to search_by_sql result.

$row = $teng->single_by_sql($sql, [\@bind_values, [$table_name]])

get one record from your SQL.

    my $row = $teng->single_by_sql(q{SELECT id,name FROM user WHERE id = ? LIMIT 1}, [1], 'user');

This is a shortcut for

    my $row = $teng->search_by_sql(q{SELECT id,name FROM user WHERE id = ? LIMIT 1}, [1], 'user')->next;

But optimized implementation.

$row = $teng->single_named($sql, [\%bind_values, [$table_name]])

get one record from execute named query

    my $row = $teng->single_named(q{SELECT id,name FROM user WHERE id = :id LIMIT 1}, {id => 1}, 'user');

This is a shortcut for

    my $row = $teng->search_named(q{SELECT id,name FROM user WHERE id = :id LIMIT 1}, {id => 1}, 'user')->next;

But optimized implementation.

$sth = $teng->execute($sql, [\@bind_values])

execute query and get statement handler. and will be inserted caller's file and line as a comment in the SQL if $ENV{TENG_SQL_COMMENT} or sql_comment is true value.


Creates a new transaction scope guard object.

    do {
        my $txn = $teng->txn_scope;

        $row->update({foo => 'bar'});


If an exception occurs, or the guard object otherwise leaves the scope before $txn->commit is called, the transaction will be rolled back by an explicit "txn_rollback" call. In essence this is akin to using a "txn_begin"/"txn_commit" pair, without having to worry about calling "txn_rollback" at the right places. Note that since there is no defined code closure, there will be no retries and other magic upon database disconnection.

$txn_manager = $teng->txn_manager

Create the transaction manager instance with specified txn_manager_class.


start new transaction.


commit transaction.


rollback transaction.


finish transaction.

$teng->do($sql, [\%option, @bind_values])

Execute the query specified by $sql, using %option and @bind_values as necessary. This pretty much a wrapper around


get database handle.


connect database handle.

connect_info is [$dsn, $user, $password, $options].

If you give \@connect_info, create new database connection.


Disconnects from the currently connected database.


set row object creation mode.


set SQL type application mode.

see apply_sql_types in "METHODS" in Teng::Iterator


set SQL type guessing mode. this implies apply_sql_types true.

see guess_sql_types in "METHODS" in Teng::Iterator

$teng->set_boolean_value($true, $false)

set scalar to correspond boolean. this is ignored when apply_sql_types is not true.

  $teng->set_boolean_value(JSON::XS::true, JSON::XS::false);
 $teng->load_plugin($plugin_class, $options);

This imports plugin class's methods to $teng class and it calls $plugin_class's init method if it has.

 $plugin_class->init($teng, $options);

If you want to change imported method name, use alias option. for example:

 YourDB->load_plugin('BulkInsert', { alias => { bulk_insert => 'isnert_bulk' } });

BulkInsert's "bulk_insert" method is imported as "insert_bulk".


handling error method.


check connected or not.


reconnect database



How do you use display the profiling result?

use Devel::KYTProf.


Teng does not support triggers (NOTE: do not confuse it with SQL triggers - we're talking about Perl level triggers). If you really want to hook into the various methods, use something like Moose, Mouse, and Class::Method::Modifiers.



This module was forked from DBIx::Skinny, around version 0.0732. many incompatible changes have been made.


No bugs have been reported.


Atsushi Kobayashi <nekokak __at__>

Tokuhiro Matsuno <>

Daisuke Maki <>





  git clone git://  


Copyright (c) 2010, the Teng "AUTHOR". All rights reserved.

This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See perlartistic.