Why do I get Unable to Open Database file? - ios

Question

I am a beginner in iOS development and I want to develop a database in my application. However, When I try to create the database it says unable to open database file.
For clarification (https://github.com/stephencelis/SQLite.swift/blob/master/Documentation/Index.md)
My code for the db development is as follow
static func DB(){
do {
let db = try Connection("db.sqlite3")
let users = Table("users")
let id = Expression<Int64>("id")
let name = Expression<String?>("name")
let email = Expression<String>("email")
try db.run(users.create { t in
t.column(id, primaryKey: true)
t.column(name)
t.column(email, unique: true)
})
} catch {
print("Dim background error")
}
}
I trigger this method from app delegate file
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
// Override point for customization after application launch.
AppCommon.DB()
return true
}
How to fix this issue? Please help me out, I really need your help..!

Answer 1

On iOS, you can't create files where you want. A correct place (among others) is in the documents directory.
Quoting the documentation of the library you are using https://github.com/stephencelis/SQLite.swift/blob/master/Documentation/Index.md#connecting-to-a-database:
On iOS, you can create a writable database in your app’s Documents directory.
let path = NSSearchPathForDirectoriesInDomains(
.DocumentDirectory, .UserDomainMask, true
).first!
let db = try Connection("\(path)/db.sqlite3")

Answer 2

Swift 5
Path of Documents directory is now an array of strings
let path = NSSearchPathForDirectoriesInDomains(
.documentDirectory, .userDomainMask, true)
let db = try Connection("\(path.first ?? "")/db.sqlite3")