OR

"select dm_id  from desease_details where sy_id = $val OR sy_id = $val2"

 

-- Jason
"It's Just Ones and Zeros"

below are my sample table

-------------------------
id(pk) |  sy_id  |  dm_id
-------------------------
  1    |    1    |    1
  2    |    2    |    1
  3    |    1    |    2
  4    |    4    |    3
--------------------------

as my first post "select * from table where sy_id = 1 and sy_id = 2"
because i want to get the row for column dm_id = 1

hope you guys understand my explaination. thnx again  

I do understand what you're asking for which is why based on the info provided I said to use OR.... change the AND in your query to OR.

select * from table where sy_id = 1 OR sy_id = 2

But given this new info it shows tha using OR will give you the 2 rows you seek plus an additional row.

But note -- your AND condition will never work. The sy_id cannot be 1 AND 2 (in the same row).

So....to get the 2 rows you see AND ONLY the 2 rows you seek you will need to add additional criteria to your select.

Like this....

select * from table where sy_id = 1 OR sy_id = 2 and dm_id <> 2

or

select * from table where dm_id = 1

 

-- Jason
"It's Just Ones and Zeros"

What about something like this ?
SELECT dm_id
FROM desease_details
WHERE sy_id = $val OR sy_id = $val2
GROUP BY dm_id
HAVING COUNT(*) = 2

Hope This Helps, PH.
FAQ219-2884: How Do I Get Great Answers To my Tek-Tips Questions?
FAQ181-2886: How can I maximize my chances of getting an answer?

thanks for reply guys, but the table dont actually like above,for some case, it can be like below

-------------------------
id(pk) |  sy_id  |  dm_id
-------------------------
  1    |    1    |    1
  2    |    2    |    1
  3    |    1    |    2
  4    |    4    |    3
  5    |    1    |    4
  6    |    3    |    4
  7    |    4    |    4
--------------------------

if you can see, the desease dm_id=4 has 3 symptom sy_id, 1,3,4

ya, i know to use AND is imposibble, and i think for OR also not kinda work out dude

any suggest? really appreciate it guys

You need to clearly define what you're trying to do.

-- Jason
"It's Just Ones and Zeros"

Did you try my suggestion ?

the situation is like this, this is for desease detection, to make it simple, there are 2 table which are symptom and desease.

The desease are determine by its symptom and 1 desease may have 1 or more symptom.

the table above is for the desease table, sy_id is for symptom id(fk from symptom table) and dm_id is for desease master id (fk from desease master table)

to use the system, user will only choose the symptom (checkbox) then send the value to db.  

phv: yup, try already, but not quit work for the table i newly create the desease id = 4...  

perharps you mean to say

select * from table where column sy_id = $val  ?

No way to edit posts here !

select * from table where sy_id = $val  ?

you need to use intersect

select dm_id from table where sy_id = 1
intersect
select dm_id from table where sy_id = 2

will return only the dm_id value = 1