[SOLVED] Releasing SQLite resources in F#

Releasing SQLite resources in F#

Consider the following F# script, which creates a simple SQLite database and table, and then should delete it. However, the SQLite obejct doesn't seem to be disposed of properly and isn't releasing its lock on the file.

#r @"C:\Path\To\System.Data.SQLite.dll"

open System.Data.SQLite

let createTable() = 
    use db = new SQLiteConnection(@"Data Source=test.sqlite")
    db.Open()
    let command = new SQLiteCommand("CREATE TABLE TestItems (ColA ColB)", db)
    command.ExecuteNonQuery() |> ignore
    db.Close()

createTable()

// System.IO.IOException: The process cannot access the file '[...]\test.sqlite' 
// because it is being used by another process.
System.IO.File.Delete("test.sqlite")

I'm pretty poor at F#, but my understanding of use is that the object's resources will be disposed of when it goes out of scope, yet that appears to not be the case in this instance. I've tried calling Dispose() to no avail as well.

Can anyone shed light on how I can properly dispose of SQLite objects in F#?

Solution

The SQLiteCommand needs to be disposed as well, as it also implements IDisposable according to the docs: https://www.devart.com/dotconnect/sqlite/docs/Devart.Data.SQLite~Devart.Data.SQLite.SQLiteCommand_members.html (via System.ComponentModel.Component

Using use binding instead of let for command should solve the issue.