Boolean determining if multi-valued Many2Many and One2Many fields are expanded into separate rows.

Data Type

bool

Default Value

false

Remarks

By default Many2Many and One2Many fields are collapsed into single values separated by commas. For example, a record in calendar_event IDs will generate a result like this if partners 13 and 57 are attending.

SELECT id, name,                           partner_ids, x_custom_ids FROM calendar_event
--      1  'Meet With Potential Customer'  '13,57'      '1,2'

With this option enabled, the adapter will expand each combination of multi-valued field values across multiple rows. This means that row data will be duplicated but makes it simpler to JOIN between tables that are linked by multi-valued references.

In addition, the adapter will use a separate primary key called id:multi since id) not unique when rows are duplciated. This primary key is generated client-side and its use should be avoided in filters, since it depends upon the exact rows returned by any filters evaluated by Odoo.

SELECT "id:multi", id, name,                          partner_ids, x_custom_ids FROM calendar_event
--      1:1        1  'Meet With Potential Customer'  13           1
--      1:2        1  'Meet With Potential Customer'  57           1
--      1:3        1  'Meet With Potential Customer'  13           2
--      1:4        1  'Meet With Potential Customer'  57           2

Note that this option does not affect how INSERTs are processed. If you want to insert a record containing a multi-valued field you must always insert using a comma-separated value.