>>

>>;with cte as (SELECT Client.Numero, 3958.75586574*ACOS(
>> CASE WHEN SIN(@Latitude3/57.2957795130823)*SIN(Client.Latitude/57.2957795130823)+
>>           COS(@Latitude4/57.2957795130823)*COS(Client.Latitude/57.2957795130823)*
>>           COS(Client.Longitude/57.2957795130823-@Longitude3/57.2957795130823)<-1
>>           THEN -1
>>      WHEN SIN(@Latitude5/57.2957795130823)*SIN(Client.Latitude/57.2957795130823)+
>>           COS(@Latitude6/57.2957795130823)*COS(Client.Latitude/57.2957795130823)*
>>           COS(Client.Longitude/57.2957795130823-@Longitude4/57.2957795130823)>1
>>           THEN 1
>>      ELSE SIN(@Latitude7/57.2957795130823)*SIN(Client.Latitude/57.2957795130823)+
>>           COS(@Latitude8/57.2957795130823)*COS(Client.Latitude/57.2957795130823)*
>>           COS(Client.Longitude/57.2957795130823-@Longitude5/57.2957795130823)
>> END) as Distance
>>
>>FROM dbo.Client
>>
>>
>> WHERE (Client.Latitude>=@Latitude-250/111.0 AND Client.Latitude<=@Latitude2+250/111.0) AND
>>(Client.Longitude>=@Longitude-250/111.0 AND Client.Longitude<=@Longitude2+250/111.0) )
>>
>>select * from cte where Distance <=250

>
>Thanks, I am always trying to avoid that syntax as it makes it more difficult to migrate to another backend.

Instead of using CTE use derived table.