MSSQL SELECT WITH CASE STATEMENT IN WHERE CLAUSE

Hello,
I'm trying to do something like this :

select table1.A

from table1 , (select X , Y , Z  from table2 WHERE clause condition ) SUB

where table1.B = 0 and table1.C = 1 and

if  sub.X = 1 => table1.Y = SUB.Y

elseif sub.X = 0 => table1.Y not in (select Y  from table2 WHERE clause condition)

else if there is no result in the sub query , no join with sub, return all the result from table1....)

/*******/

in fact I have a table of product. (table1)

and I have another table (table2)  where I managed the right access for a customer.

if there is no entry in table2, no restriction for the customer in table1 (last else)

if there is an entry in table2, there is a restriction for the customer for  specific product.

there is 2 type of restriction, in the X column (bit).

0 = no access for this product (but yes access to other product)
1 = only access for this product  (so no access for other product)

Many thanks for your help.
bruno_boccaraAsked:
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

x
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

John_VidmarCommented:
Would've been easier with real table/field names:
SELECT	a.A
from	table1	a
LEFT
JOIN	table2	b	ON	a.Y = b.Y
			AND	b.X = 1
WHERE	a.B = 0
AND	a.C = 1

UNION

SELECT	a.A
from	table1	a
LEFT
JOIN	table2	b	ON	a.Y = b.Y
			AND	b.X = 0
WHERE	a.B = 0
AND	a.C = 1
AND	b.Y IS NULL

Open in new window

0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
bruno_boccaraAuthor Commented:
In fact, I made this query:

SELECT DISTINCT E.COL_ED 

FROM EDITEUR E , (SELECT COL_ED , BLOCK_TYPE , CTNUM , PLATFORME FROM RE_ED_BLOCK REB WHERE CTNUM = '0000008909' AND PLATFORME = 'INTRANET') SUB

WHERE Interne = 0 AND ED_ACTUEL = 1

AND (

(SUB.BLOCK_TYPE = 1 AND E.COL_ED = SUB.COL_ED)   /* IT WORKS */

OR

(SUB.BLOCK_TYPE = 0 AND E.COL_ED NOT IN (SELECT COL_ED FROM RE_ED_BLOCK REB WHERE CTNUM = SUB.CTNUM AND PLATFORME = SUB.PLATFORME ))  /* IT WORKS */

 OR (NOT EXISTS(SELECT COL_ED FROM RE_ED_BLOCK REB WHERE CTNUM = SUB.CTNUM AND PLATFORME = SUB.PLATFORME) AND E.COL_ED = E.COL_ED)  /* IT DOESN'T WORKS */
)

Open in new window


the third OR condition do not work.  I want to avoid a join with SUB table if there is no entry and to return all entries from EDITEUR  (with only condition Interne = 0 AND ED_ACTUEL = 1 )

Many thanks for any help.
0
bruno_boccaraAuthor Commented:
Hello John,
I can't make a left outer join between table1 (EDITEUR) and table2 (RE_ED_BLOCK).
0
bruno_boccaraAuthor Commented:
One way is to do this with INTERSERCT or EXCEPT, but I have a problem when there is no entry in the second table (RE_ED_BLOCK ). I can't return in this case entries from table1 (EDITEUR )
0
bruno_boccaraAuthor Commented:
this could be a solution if I could make a left outer join between the two table.

anyway, I found a different way , using fucntion, intersect and except....
0
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Microsoft SQL Server

From novice to tech pro — start learning today.