Question

I have this question for you,why would this give me the updated value with the original in the same field”Ohio” that was the original…now after proc”Ohio OH” I only want the updated value.Th function returns only one value I tested it before using it in the proc. Thanks in advance for looking into it guys.

CREATE PROC [dbo].[Changestringstate] 
AS 
    UPDATE stage.statetable 
    SET    originalstatename = Rtrim(originalstatename) --avoiding trailing space issues 

    UPDATE stage.statetable 
    SET    originalstatename = Replace(originalstatename, 
                               Substring (originalstatename, 
                               Len (originalstatename) - ( 
                               Charindex(' ', Reverse( 
                               originalstatename)) ) + 1, Len(originalstatename) 
                               ), 
           dbo.Changefunction(originalstatename)) 

Answer 1

Consider this example

create table statetable
(
  originalstatename varchar(100)
);
insert statetable values ('ohio oh');
GO

CREATE PROC [dbo].[Changestringstate] 
AS 
    UPDATE statetable 
    SET    originalstatename = Rtrim(originalstatename) --avoiding trailing space issues 

    UPDATE statetable 
    SET    originalstatename = Replace(originalstatename, 
                               Substring (originalstatename, 
                               Len (originalstatename) - ( 
                               Charindex(' ', Reverse( 
                               originalstatename)) ) + 1, Len(originalstatename) 
                               ), 
           'ohia') 
GO
exec changestringstate;
select * from statetable;

--- result
ohioohia

What your proc is doing:

The entire SUBSTRING block does one thing, which is to remove everything after the LAST SPACE. This is excluding trailing spaces, since they are trimmed off in the prior UPDATE. Examples of what it does:

state name    |  Substring result
Ohio OH          " OH"
Mi Ohio OH       " OH"
New York NY      " NY"

Then comes the REPLACE block, which looks for the substring result, and replaces EVERY occurence of it with whatever comes back from dbo.Changefunction(). Let’s say it comes back with “xyz”.

state name    |  Substring result | after replace
Ohio OH          " OH"            | Ohioxyz
Mi Ohio OH       " OH"            | Mixyzioxyz
New York NY      " NY"            | New Yorkxyz

Hope that helps you understand your proc, so that you can fix it accordingly.