ORA-30036: unable to extend segment by 8 in undo tablespace 'UNDO'

Came across this error while executing an oracle script:

ORA-30036: unable to extend segment by 8 in undo tablespace 'UNDO'
ORA-06512: at line 13

Reason:
tablespace 'UNDO' is reaching limits

Tablespaces view from http://127.0.0.1:8080/apex/

Solution:
You should resize the UNDO tablespace size. Execute this as sysdba.

SQL> alter database datafile '/usr/lib/oracle/xe/app/oracle/product/10.2.0/server/dbs/bigtbs_f2.dat' 
      AUTOEXTEND ON MAXSIZE 10000M;

Also could add a datafile to UNDO tablespace if you have room. But I haven't tried this.