How are SQLite records updated?

Question

This code's syntax is accepted:

public async Task UpdateLocationAsync(SOs_Locations locations)
{
    var db = new SQLiteAsyncConnection(SQLitePath);
    await db.UpdateAsync(locations);
}

...but I don't grok how the SQLite engine knows which record to update when it is simply passed the class instance. Is it the case that the SQLite or SQLite-net engine peeks at the ID value and behind the scenes does a (in SQLese):

UPDATE SOs_Locations
Set Bla = Bla, etc.
WHERE ID = locations.Id

?

Answer 1

That's exactly what it does. You can check the source of the method here:

var q = string.Format ("update \"{0}\" set {1} where {2} = ? ", map.TableName, string.Join (",", (from c in cols
        select "\"" + c.Name + "\" = ? ").ToArray ()), pk.Name);

Of course you can always execute your own SQL if you need more control:

db.ExecuteAsync("UPDATE SOs_Locations Set Bla = ?, WHERE ID = ?", bla, id);