@Mark Hurd, thanks for pointing out the error.
this will work (if you are using Postgresql, Sql Server 2008):
create table products
(
product_id int not null
);
insert into products values(1),(2),(10),(100);
SELECT
CASE
WHEN EXISTS(
SELECT 1
FROM (values(1),(10),(100)) as x(id)
WHERE x.id NOT IN (select product_id from products))
THEN 0 --'NOT ALL'
ELSE 1 -- 'ALL'
END
If you are using MySQL, make a temporary memory table(then populate 1,10,100 there):
create table product_memory(product_id int) engine=MEMORY;
insert into product_memory values(1),(10),(100);
SELECT
CASE
WHEN EXISTS(
SELECT 1
FROM product_memory
WHERE product_memory.id NOT IN (select product_id from products))
THEN 0 -- 'NOT ALL'
ELSE 1 -- 'ALL'
END
On your C# code:
bool isAllExist = (int)(new SqlCommand(queryHere).ExecuteScalar()) == 1;
[EDIT]
How can I write a query that will return a row if all the product id's exist and no row if one or more product id's does not exist?
Regarding, returning a row(singular) if all rows exists, and no row to be returned if one or more product id does not exists:
MySql:
SELECT 1
WHERE
NOT EXISTS(
SELECT 1
FROM product_memory
WHERE product_memory.id NOT IN (select product_id from products) )
Posgresql, Sql Server 2008:
SELECT 1
WHERE
NOT EXISTS(
SELECT 1
FROM (values(1),(10),(100)) as x(id)
WHERE x.id NOT IN (select product_id from products) )
Then on your C# code:
var da = new SqlDataAdapter(queryhere, connectionhere);
var dt = new DataTable();
da.Fill(dt);
if (dt.Rows.Count > 0)
return true;
else
return false;
Or just make the condition shorter:
return dt.Rows.Count > 0;