T SQL Conditional String Concatenation

Question

Have a 5 columns of address data. I need to concatenate these fields into a single address with spaces in between the values if they exist. If the column has a null value

Answer 1

Use the "+" to concatenate strings in TSQL:

SELECT CASE 
         WHEN LEN(p.street_number) > 0 THEN p.street_number + ' ' 
         ELSE '' 
       END +
       CASE 
         WHEN p.street_ext = 50 THEN '1/2'
         WHEN LEN(p.street_ext) > 0 THEN ''
         ELSE p.street_ext
       END + ' ' +
       CASE 
         WHEN LEN(p.street_direct) > 0 THEN p.street_direct + ' '
         ELSE ''
       END + 
       CASE 
         WHEN LEN(p.site_street) > 0 THEN p.site_street + ' '
         ELSE ''
       END  + 
       CASE 
         WHEN LEN(p.site_address) > 0 THEN p.site_address + ' '
         ELSE ''
       END AS full_address
FROM PARCEL p

The LEN function returns zero if the string value is NULL, or a zero length string.