SQL Server 2022

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select @@version;


(No column name)


Microsoft SQL Server 2022 (RTM) - 16.0.1000.6 (X64) 
 Oct  8 2022 05:58:25 
 Copyright (C) 2022 Microsoft Corporation
 Express Edition (64-bit) on Windows Server 2019 Standard 10.0 <X64> (Build 17763: ) (Hypervisor)



CREATE TABLE Example
(
   ColumnA  SMALLINT ,
   ColumnB  INT
);


INSERT INTO Example (ColumnA,ColumnB) VALUES
  (1,1),
  (2,2),
  (3,4);

SELECT * FROM Example


ColumnA
ColumnB


1
1

2
2

3
4


 SELECT *, CAST(
                CASE WHEN ColumnA IS NOT NULL AND (ColumnB = 0 OR ColumnB IS NULL) THEN CAST(ColumnA as Varchar(10))
                     WHEN ColumnA IS NOT NULL AND ColumnB IS NOT NULL AND ColumnB > 0 THEN CONCAT(ColumnA, '.', ColumnB) 
                END 
                AS NUMERIC(2,1)
               ) AS 'VERSION'
FROM Example


ColumnA
ColumnB
VERSION


1
1
1.1

2
2
2.2

3
4
3.4