SELECT
column1,
column2,
(CASE WHEN column1=NULL THEN @NEW_column =column2
WHEN column1!=NULL THEN @NEW_column =column1
END) AS NEW_column,
FROM my_table
In the above select statement , i am creating a new variable called
NEW_column and the value of it should be based on the conditions in case statement. When i run this query value is "NEW_column" is returned as NULL. Can anyone help me solve this logical error?
You need to write column1 is null
similarly column1 is not null
SELECT
column1,
column2,
CASE WHEN column1 is NULL THEN column2
WHEN column1 is not NULL THEN column1
END AS NEW_column,
FROM my_table
OUTPUT:
col1 col2 newcol
3 null 3
null 4 4
5 null 5
It means you don't get any value with your conditions
There are several way to debug the your SQL statement:
sample
SELECT
column1,
column2,
ISNULL(column1,column2) AS NEW_column
FROM my_table
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