Oracle 21c

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CREATE TABLE table_name (ID, CITY, COUNTRY) AS
SELECT 1, 'Praha 4',    'CZE' FROM DUAL UNION ALL
SELECT 2, 'Dublin 1',   'GBR' FROM DUAL UNION ALL
SELECT 3, 'Budapest 3', 'HUN' FROM DUAL UNION ALL
SELECT 4, 'Dublin',     'GBR' FROM DUAL UNION ALL
SELECT 5, 'Praha 7',    'CZE' FROM DUAL UNION ALL
SELECT 6, 'Budapest',   'HUN' FROM DUAL;
6 rows affected

SELECT *
FROM   table_name
WHERE  REGEXP_LIKE(city, '\s+\d+$')
AND    city NOT LIKE 'Praha%'


ID
CITY
COUNTRY


2
Dublin 1
GBR

3
Budapest 3
HUN


SELECT *
FROM   table_name
WHERE  TO_NUMBER(
         SUBSTR(city, INSTR(city, ' ', -1))
         DEFAULT NULL ON CONVERSION ERROR
       ) IS NOT NULL
AND    city NOT LIKE 'Praha%'


ID
CITY
COUNTRY


2
Dublin 1
GBR

3
Budapest 3
HUN