Excuting SQL-Statements after error in same transaction ?

I'm tying to estimate the expense of migrating some application from Oracle to PostgreSQL
I'm happy to see, that there are many simmilarities in SQL and PostgreSQl has also all kinds of DML-triggers.

But one difference twould lead into much reprogramming:
If there is an error in a transaction, I can't execute any further sql-statements in tge same transaction.
I the existing code I have many expected errors like in this example:

mkl=> BEGIN;
BEGIN
mkl=> insert into categories ( id, user_id, name, name_lc ) values ( 10002, 4711, 'FOO', 'foo' );
ERROR: duplicate key violates Unique-Constraint »pk_categories«
mkl=> udpate categories set user_id=4711, name='FOO', name_lc='foo' WHERE id=10002;
ERROR: Fehler »syntax error« bei »udpate« at character 1
mkl=> update categories set user_id=4711, name='FOO', name_lc='foo' WHERE id=10002;
ERROR: actual tranaction aborded, commands are ignoord until the end of the transaction

(error-mesages translated by hand into english)

Is ist possible to change this behavior p.e with a SET-command ?