As relational name is not given in the field definition, system generates the relational table's name automatically. In this case the table name is "account_tax_sale_order_line_rel".

There is a following rule for that:

If name is not given, it is automatically generated from provided "model_name" and "comodel_name" after sorted by alphabetical order (account_tax, sale_order_line = account_tax_sale_order_line_rel)

Original Code in framework:

tables = sorted([model._table, comodel._table])
relation = '%s_%s_rel' % tuple(tables)

Sudhir Arya
ERP Harbor Consulting Services
Skype:	sudhir@erpharbor.com
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