issue with CASE combined with an OR - sql

Question

SELECT
Siren,
CASE WHEN Code_Juridique LIKE 'M%' AND Enseigne IS NOT NULL AND Enseigne <> '' --ok
THEN 'Enseigne : ' + Enseigne
WHEN (Sigle IS NULL OR Sigle ='')
AND (Enseigne IS NULL OR Enseigne ='')
THEN '' -- ok
WHEN
(Sigle IS NOT NULL OR Sigle <> '' ) THEN 'Sigle : ' + Sigle
ELSE 'Sigle / Enseigne : ' + Sigle + ' / ' + Enseigne
END as SigleEnseigne1,
Sigle,
Enseigne,
Code_Juridique
FROM #JohnJack
The code is straightforward.
Issue lies with the third when as you can see below
I should have have nothing on my 4th and 5th line, yet it is giving me Sigle :
What I want is to have the column SigleEnseigne1 on the 4th and 5th line , to be empty
Thanks for your insights

Answer 1

Try this:
SELECT
Siren,
CASE WHEN ( Code_Juridique LIKE 'M%' ) AND ( IsNull( Enseigne, '' ) <> '' )
THEN 'Enseigne : ' + Enseigne
WHEN ( IsNull( RTrim(LTrim(Sigle)), '') = '') AND ( IsNull( Enseigne, '' ) = '')
THEN '' -- ok
WHEN ( IsNull( RTrim(LTrim(Sigle)), '' ) <> '' )
THEN 'Sigle : ' + RTrim(LTrim(Sigle))
ELSE
'Sigle / Enseigne : ' + IsNull( RTrim(LTrim(Sigle)), '' ) + ' / ' + Enseigne
END as SigleEnseigne1,
Sigle,
Enseigne,
Code_Juridique
FROM #JohnJack

Answer 2

Besides stating the obvious that a (TRUE OR FALSE) = TRUE
I would simplify and bullet proof the code by using ISNULL() and LEN().
SELECT
Siren,
CASE WHEN Code_Juridique LIKE 'M%' AND LEN(ISNULL(Enseigne,'')) > 0 --ok
THEN 'Enseigne : ' + Enseigne
WHEN (LEN(ISNULL(Sigle, '')) = 0)
AND (LEN(ISNULL(Enseigne, '')) = 0)
THEN '' -- ok
WHEN
LEN(ISNULL(Sigle, '')) > 0 THEN 'Sigle : ' + Sigle
ELSE 'Sigle / Enseigne : ' + ISNULL(Sigle, '') + ' / ' + ISNULL(Enseigne, '')
END as SigleEnseigne1,
Sigle,
Enseigne,
Code_Juridique
FROM #JohnJack
How would your code react if those fields contain whitespaces? LEN automatically trims trailing whitespaces.

Answer 3

This line is causing your probelm:
(Sigle IS NOT NULL OR Sigle <> '' ) THEN 'Sigle : ' + Sigle
...but that is only obvious because you state that you dont want this result. Other than that the code acts as would be expected.
The simplest solution would be to take out:
'Sigle : ' + Sigle
but that may or may not be precisely what you are looking for. Based on the given information it is the solution but there is not an abundance of information to work off
If you are trying to get non null values to print then it should be an AND rather than an OR. When you use an OR it will return true if EITHER condition is true.

Answer 4

I'm not sure why you have this when
WHEN (Sigle IS NULL OR Sigle = '')
AND (Enseigne IS NULL OR Enseigne ='')
THEN '' -- ok
As what you want is SigleEnseigne1 to be NULL or '' when Sigle is NULL or '' don't you need this when instead
WHEN (Sigle IS NULL OR Sigle = '') THEN ''
There can also be the problem that Sigle is not the empty string and has whitespaces. You can use the LTRIM() and RTRIM() functions

Answer 5

It took me the weekend but actually, I figured out My mistake.
Sorry for the mess
The answer is below
SELECT
Siren,
CASE WHEN ( Code_Juridique LIKE 'M%' ) AND ( IsNull( Enseigne, '' ) <> '' )
THEN 'Enseigne : ' + Enseigne
WHEN ( IsNull( RTrim(LTrim(Sigle)), '') = '') AND ( IsNull( Enseigne, '' ) = '')
THEN '' -- ok
WHEN (Sigle IS NOT NULL OR Sigle <> '') AND (Enseigne IS NULL OR Enseigne = '')
THEN 'Sigle : ' + RTrim(LTrim(Sigle))
WHEN (Sigle IS NULL OR Sigle = '') AND (Enseigne IS NOT NULL OR Enseigne <> '')
THEN ''
WHEN
(Sigle IS NOT NULL OR Sigle <> '') AND (Enseigne IS NOT NULL OR Enseigne <> '')
THEN 'Sigle / Enseigne : ' + IsNull( RTrim(LTrim(Sigle)), '' ) + ' / ' + Enseigne
END as SigleEnseigne1
FROM John_Jack
Have a great end of the year