The task is to convert house numbers that are stored in column with character
datatype to numeric value. We will use MS-Acces VAL()
function that recives char input and returnts Integer as output. Suppose that
we have 3 address coumns in table clients: city, street, house. Let's
try   VAL() function on house column and see the consequences.
SELECT VAL(house) AS house_number, house, street
The query returns results like these:
|109||10 9-C||ahen str|
|0||N-8 Apt406||ost klapen str|
|780||780 n-19||ukitgam 780/19|
|15||15-H Ap.4||via domani|
Pay attention that character value "10 9-C" was converted to number
On the other hand VAL() function was not able to convert string value "A203/58"
to any number but 0.