Drop constraint when is postgres

issue11198

__init__.py

@@ -27,6 +27,7 @@ def register():
     Pool.register(
         bank.Bank,
         bank.BankAccount,
+        bank.BankAccountNumber,
         depends=['bank'],
         module='party_company', type_='model')
     Pool.register(

bank.py

@@ -3,6 +3,7 @@
 from trytond.model import fields
 from trytond.pool import Pool, PoolMeta
 from trytond.transaction import Transaction
+from trytond import backend
 from . import party
 
 
@@ -59,3 +60,22 @@ class BankAccount(metaclass=PoolMeta):
     @classmethod
     def set_owners_by_companies(cls, records, name, value):
         cls.write(records, {'owners': value})
+
+
+class BankAccountNumber(metaclass=PoolMeta):
+    __name__ = 'bank.account.number'
+
+    @classmethod
+    def __register__(cls, module_name):
+        cursor = Transaction().connection.cursor()
+
+        # since issue11198 fill or create bank from IBAN and enforce uniqueness
+        # replace default sql_constrain (keep same name) that always return false
+        exist = backend.TableHandler.table_exist(cls._table)
+        if exist and backend.name == 'postgresql':
+            cursor.execute("ALTER TABLE bank_account_number DROP CONSTRAINT "
+                "IF EXISTS bank_account_number_number_iban_exclude")
+            cursor.execute("ALTER table bank_account_number add constraint "
+                "bank_account_number_number_iban_exclude check (type != 'x')")
+
+        super(BankAccountNumber, cls).__register__(module_name)