Removing last two digits
It's just a simple integer division. 

So select (123456/100).

But that only valid is the column is integer type.

The example provided is big. If the column is integer then using a simple case logic is suffice. First check if the value is bigger than 99 then divide by 100, if not use what it is.

Declare @field_name;
Set @field_name = 123456;

Select (case when @field_name &gt; 99 then (@field_name/100) Else @field_name);


change field name to any column you wish and adjust the query to target table. 

Rather than using convert or cast , integer divide provide less cpu cycle because of dedicated math block inside the cpu. When using convert or cast you have many more cpu cycle because it will also include memory operation.