Guide to protect .SQLITE db file in directory in application level and OS level

i am newbie,When i have to launch my application each time sqlite .db file created in below directory

Library/Application Support/iPhoneSimulator/6.1(example)/Applications/409235C4-9C9E-41A2-9058-FF848D2384FD(example)/Documents/name.db

now i want to make secure for this .db file.So i am tried to encrypt data before adding,tried to set NSFilePosixPermissions but its not working for .db file.So my doubt is any possibilities protect .db file in application level and also OS level such as can't copy,rwx permissions,if any one open file ask passcode,In app level also access database via passcode something like.any one guide to me.