Database query

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I am doing a DAOdatabase programming in Visual C++ 6.0, wherein I want to give a query to check if a particular item is present in Table field or not. That is, I want to perform a set of functions only if the record is present in the table field otherwise not.
Can anyone please suggest how to implement it?

I think "select (count)from <tablename> where (condition)" can check if the item is present.But I did not get its correct implementation in VC++.
If i get the return value of count, i can use it in my program.

I even tried it with try and catch method, but i got some error.

Please help.

Timkee

Posted 18-Aug-10 21:02pm

gargimails

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Uwe Keim · Answer 1 · 2010-08-19T08:47:00

Solution 1

The syntax should be "COUNT(*)", e.g.

SELECT COUNT(*)
FROM Customer
WHERE ID=459

Maybe you could take a look at the definition of the COUNT SQL syntax[^].

Posted 19-Aug-10 8:47am

Uwe Keim

Nyarost · Answer 2 · 2010-08-19T10:10:00

Solution 2

Don't know about DAO. For MySQL this would be optimal:

SELECT 1 FROM `table` WHERE `id` = '1' LIMIT 1

Posted 19-Aug-10 10:10am

Nyarost