napr. takto:
conn=# select * from conn.t_ulice
where to_ascii(convert(ulice using utf_8_to_iso_8859_2),'latin2') like 'vinohradska';
ulice_id | ulice | mestska_cast_id | latitude | longitude
----------+-------------+-----------------+---------------+---------------
5679 | vinohradská | 21 | 50.077638979 | 14.4511329906
5680 | vinohradská | 20 | 50.0780777777 | 14.4609392857
5681 | vinohradská | 16 | 50.0771697916 | 14.4856454861
(3 rows)
