Sql query to retrieve st number

Question

Hi,
I would like to query a street number column(varchar2) from address table.
st number could be any one of following.
1.1234
2.AHh-500
3.1700/2
4.15-A or 15A
in this case, i should get only values with numberic not any alpha or special character.
Query should return case 1, not case 2.
in case of case 3 or 4, query should return 1700 or 15(i.eif st num starts with number and has non numberic characters, it shud return only numerics)
Could anyone please post the query for this scenario?

Answer 1

Never fear, the regex man is here ... scnr. ;-) In 10g1, how about this:
WITH t AS (SELECT '1234' street
             FROM dual
            UNION
           SELECT 'AHh-500'
             FROM dual
            UNION
           SELECT '1700/2'
             FROM dual
            UNION
           SELECT '15-A'
             FROM dual
            UNION
           SELECT '15A'
             FROM dual
SELECT t.*, REGEXP_SUBSTR(t.street, '^[[:digit:]]+') street_number
  FROM t;            Using this as filter:
SELECT *
  FROM (SELECT t.*, REGEXP_SUBSTR(t.street, '^[[:digit:]]+') street_number
          FROM t
WHERE street_number IS NOT NULL
;C.