Question

I have been working with iPhone application in which i am using sqlite database. I have checked memory leak in iPad,iPhone 4 and there is no memory leaks. But same code show memory leak in iPhone-3GS. Please take a look at below scree-shot and i think there is no leak than after instruments showing me leaks. Please do advice me.

Thanks in Advance.

Answer 1

Its actually not that strange, see how you allocate memory for both Query and Query1 via [[NSArray alloc] init. But then, you overwrite the pointer of them by calling [database executeQuery:], so the allocated memory is leaked.

It looks like you don’t really need the array allocation anyway, so you can simply remove that line. However, that the [Query release] and [Query1 release] doesn’t crash the app (or at least at some later point), indicates that [database executeQuery:] return retained memory and thus delegates its ownership to the caller, which is discouraged by the memory guidelines. You should return an autoreleased object from executeQuery: and because you never use the returned value, you can simply reduce the method down to:

[self databaseOpen];
[database executeQuery:@"Delete from ActivityList"];
[database executeQuery:@"Select* from ActivityList"];