Question

Assuming the following data:

Column1 (data type: varchar(50)) -------- 11.6 -1 1,000 10'     Non-Numeric String 

I have a query, which is pulling data from this column and would like to determine if the value is a number, then return it as such in my query. So I am doing the following

SELECT CASE        WHEN IsNumeric(Replace(Column1, ''', '')) = 1 THEN Replace(Column1, ''', '')        ELSE 0    END AS NumericValue 

SQL is reporting back:

Conversion failed when converting the varchar value ‘11.6’ to data type int.

Why? I have also tried to force cast this:

SELECT CASE        WHEN IsNumeric(Replace(Column1, ''', '')) = 1 THEN cast(Replace(Column1, ''', '') AS float)        ELSE 0    END AS NumericValue 

And I got:

Error converting data type varchar to float.

Answer 1

You need to replace comma with a period:

CAST(REPLACE(column, ',', '.') AS FLOAT) 

SQL Server outputs decimal separator defined with locale, but does not unterstand anything but a period in CASTs to numeric types.