MM-relations configuration¶

Things get a bit more complicated with MM-relations, where additional configuration is required. The related properties are described below.

Tip

If all this seems a bit confusing, please refer to the chapter about mapping MM relations. Hopefully it will help (this is not a simple topic).

Properties¶

Property	Data type
additionalFields	array
mapping	Mapping configuration
multiple	boolean
sorting	string

mapping¶

Type: Mapping configuration
Description: This is similar to the mapping property for columns. It is used to define which table to link to and which column in that table contains the external primary key.
Scope: Store data

additionalFields¶

Type: array
Description: List of fields that must be stored along the local and foreign keys in the MM table. For each such field, define which TYPO3 CMS MM-table field corresponds to which external data field.
Scope: Store data

multiple¶

Type: boolean
Description: If some MM-relations exist several times in your external data (because they have various additional fields), you must set this property to 1, so that they are preserved (otherwise the TYPO3 Core Engine will take only unique “uid_local”-“uid_foreign” pairs into account).
Scope: Store data

sorting¶

Type

string

Description

Indicates that the data is to be sorted according to that particular field from the external data.

Note that since the external import relies on the TYPO3 Core Engine to store the data, which sets its own numbering for sorting, thus the value in sorting is never used as is, but just for ordering the records. So if the records in the external source are already sorted, there’s no need to define the “sorting” property.

Scope

Store data

Additional notes¶

When the additionalFields and/or multiple properties are used, additional database operations are performed to honour these settings, as it is not traditional behaviour for TYPO3 MM-relations. It should be possible with IRRE, but this isn’t supported yet.

Also note that these extra operations assume that the MM-relation is defined as originating from the currently imported table. This means that if you are importing table “foo” and its relations to table “bar”, the import script assumes that the foreign keys of table “foo” are going into the uid_local column. Importing from the “other” side is not supported yet.

Example¶

This example shows how the “employee” field of the external data is mapped to the “fe_users” table to consitute the list of members in a team.

'members' => array(
        'exclude' => 0,
        'label' => 'LLL:EXT:externalimport_tut/locallang_db.xml:tx_externalimporttut_teams.members',
        'config' => array(
                'type' => 'group',
                'size' => 5,
                'internal_type' => 'db',
                'allowed' => 'fe_users',
                'MM' => 'tx_externalimporttut_teams_feusers_mm',
                'maxitems' => 100
        ),
        'external' => array(
                0 => array(
                        'field' => 'employee',
                        'MM' => array(
                                'mapping' => array(
                                        'table' => 'fe_users',
                                        'referenceField' => 'tx_externalimporttut_code',
                                        'default' => ''
                                ),
                                'sorting' => 'rank'
                        )
                )
        )
),