Finding all the zip codes in a radius with all zip codes in the same field

 I am trying to build out an way to return all of the surrounding zip codes for a particular one in a single field, so that I can use it for additional queries.  I found this on the Salesforce Marketing Cloud Dev site for SQL:

SELECT zip , city , ROUND(6378.137 * ACOS( CASE WHEN (SIN(RADIANS((SELECT latitude FROM [ZipCode] where zip = 33308))) * SIN(RADIANS(geo.Latitude))) + (COS(RADIANS((SELECT latitude FROM [ZipCode] where zip = 33308))) * COS(RADIANS(geo.Latitude)) * COS(RADIANS(geo.Longitude) - RADIANS((SELECT longitude FROM [ZipCode] where zip = 33308)))) > 1 THEN 1 WHEN (SIN(RADIANS((SELECT latitude FROM [ZipCode] where zip = 33308))) * SIN(RADIANS(geo.Latitude))) + (COS(RADIANS((SELECT latitude FROM [ZipCode] where zip = 33308))) * COS(RADIANS(geo.Latitude)) * COS(RADIANS(geo.Longitude) - RADIANS((SELECT longitude FROM [ZipCode] where zip = 33308)))) < -1 THEN -1 ELSE (SIN(RADIANS((SELECT latitude FROM [ZipCode] where zip = 33308))) * SIN(RADIANS(geo.Latitude))) + (COS(RADIANS((SELECT latitude FROM [ZipCode] where zip = 33308))) * COS(RADIANS(geo.Latitude)) * COS(RADIANS(geo.Longitude) - RADIANS((SELECT longitude FROM [ZipCode] where zip = 33308)))) END ),0 ) AS Distance FROM [ZipCode] AS geo WHERE ROUND(6378.137 * ACOS( CASE WHEN (SIN(RADIANS((SELECT latitude FROM [ZipCode] where zip = 33308))) * SIN(RADIANS(geo.Latitude))) + (COS(RADIANS((SELECT latitude FROM [ZipCode] where zip = 33308))) * COS(RADIANS(geo.Latitude)) * COS(RADIANS(geo.Longitude) - RADIANS((SELECT longitude FROM [ZipCode] where zip = 33308)))) > 1 THEN 1 WHEN (SIN(RADIANS((SELECT latitude FROM [ZipCode] where zip = 33308))) * SIN(RADIANS(geo.Latitude))) + (COS(RADIANS((SELECT latitude FROM [ZipCode] where zip = 33308))) * COS(RADIANS(geo.Latitude)) * COS(RADIANS(geo.Longitude) - RADIANS((SELECT longitude FROM [ZipCode] where zip = 33308)))) < -1 THEN -1 ELSE (SIN(RADIANS((SELECT latitude FROM [ZipCode] where zip = 33308))) * SIN(RADIANS(geo.Latitude))) + (COS(RADIANS((SELECT latitude FROM [ZipCode] where zip = 33308))) * COS(RADIANS(geo.Latitude)) * COS(RADIANS(geo.Longitude) - RADIANS((SELECT longitude FROM [ZipCode] where zip = 33308)))) END ),0 ) <= 32.1869

What it is doing is sending each of the 90 surrounding zips are populated on their own row. What I am looking for is to put the zips together. See the examples below: Current 12345 23456 34567 45678 56789 What I want is: 12345, 23456, 34567, 45678, 56789 Please guide how to find zip codes in a radius?