Case & isnull

Transact-SQL
1

Just wanted to know whether this will work i..e. CASE & ISNULL logic

SELECT
CASE WHEN ISNULL(NodeAttribute1, '') = '' THEN CaptionDATA else NodeAttribute1 END AS NodeAttribute1
2

yes it will work ...no need for isnull(col,'') = ''

use case when col1 is null then col123

please click arrow to the left for Sample data

Sample Data 
DROP TABLE [#xyz];
GO

CREATE TABLE [#xyz]
     (
         [id] varchar(1) NULL
         , [name] VARCHAR(100)
     );
GO

INSERT INTO [#xyz] SELECT  '1', 'gary';
INSERT INTO [#xyz] SELECT   NULL, 'hope';
INSERT INTO [#xyz] SELECT   NULL, 'soap';
GO
SELECT 'data',* from #xyz 
go

SELECT 'SQL Output',
    CASE WHEN [#xyz].[id] IS NULL THEN [#xyz].[name]
        ELSE [#xyz].[id]
    END
FROM
    [#xyz];

image

2 Likes
3

You don't actually need a CASE expression:

Declare @testTable Table (NodeAttribute1 varchar(20), CaptionData varchar(20));

 Insert Into @testTable (NodeAttribute1, CaptionData)
 Values ('Node1', 'Caption1')
      , ('', 'Caption2')
      , (Null, 'Caption3')
      , ('Node4', 'Caption4');

 Select *
      , NodeAttribute1 = coalesce(nullif(tt.NodeAttribute1, ''), tt.CaptionData)
   From @testTable tt;
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