Suppose I have a table with columns user_id
, name
and the table contains data like this:
user_id name
------- -----
sou souhardya
cha chanchal
swa swapan
ari arindam
ran ranadeep
If I want to know these users ( sou
, cha
, ana
, agn
, swa
) exists in this table or not then I want output like this:
user_id it exists or not
------- -----------------
sou y
cha y
ana n
agn n
swa y
As ana
and aga
do not exist in the table it must show "n" (like the above output).
Assuming your existing checklist is not on the database, you will have to assemble a query containing those. There are many ways of doing it. Using CTEs, it would look like this:
with cte as
(
select 'sou' user_id
union all
select 'cha'
union all
select 'ana'
union all
select 'agn'
union all
select 'swa'
)
select
cte.user_id,
case when yt.user_id is null then 'n' else 'y' end
from cte
left join YourTable yt on cte.user_id = yt.user_id
This also assumes user_id
is unique.
Here is the SQLFiddle with the proof of concept: http://sqlfiddle.com/#!3/e023a0/4
Assuming you're just testing this manually:
DECLARE @Users TABLE
(
[user_id] VARCHAR(50)
)
INSERT INTO @Users
SELECT 'sou'
UNION SELECT 'cha'
UNION SELECT 'ana'
UNION SELECT 'agn'
UNION SELECT 'swa'
SELECT a.[user_id]
, [name]
, CASE
WHEN b.[user_id] IS NULL THEN 'N'
ELSE 'Y'
END AS [exists_or_not]
FROM [your_table] a
LEFT JOIN @Users b
ON a.[user_id] = b.[user_id]
You didn't provide quite enough information to provide a working example, but this should get you close:
select tbl1.user_id, case tbl2.user_id is null then 'n' else 'y' end
from tbl1 left outer join tbl2 on tbl1.user_id = tbl2.user_id
;with usersToCheck as
(
select 'sou' as userid
union select 'cha'
union select 'ana'
union select 'agn'
union select 'swa'
)
select utc.userid,
(case when exists ( select * from usersTable as ut where ut.user_id = utc.userid) then 'y' else 'n' end)
from usersToCheck as utc
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