![]() ![]() Specifically, I didn’t want to double up on the foreign key/ primary key columns. Note that I listed out each column here because I didn’t want to include all columns. Here, we query three tables and insert the results into a table called PetsTypesOwners. You can select data from multiple tables, then have the destination table’s definition be based on the result set. In this example, I filter the data to just those pets who have a date of birth (DOB) from before the 1st of June, 2020. ![]() The SELECT statement can do the usual SELECT statement stuff, such as filtering the results with a WHERE clause. That is, it will add new rows to the table, while keeping any existing rows. This will append the data to any existing data. If you want to insert data into a table that already exists, use the INSERT INTO. AS SELECT statement again, we get an error, due to the table already existing. Petid | pettypeid | ownerid | petname | dob If we select both tables, we can see they both have the same data. The SQL standard requires parentheses around the subquery clause, but they may be optional in your DBMS (for example PostgreSQL). However, it doesn’t include indexes and other column attributes. This creates a new table called Pets2 (with the same columns as Pets), and inserts the query results into it. Here’s a basic example to demonstrate selecting and inserting the data into a new table. AS SELECT statement enables you to insert the results of a query into a new table. So 'Quantity' class is not a valid type for SQLite DB value.but turns out neither is object.has anyone idea for a work around for this.or some advice on how to refactor to resolve this?Īny help or point in the right direction is appreciated thank Yĭatabase = DependencyService.Get().The SQL CREATE TABLE. So.yeah as I said all works fine and dandy.But now I would like to load the ProductModel list from a table in SQLite.I have already used SQLite basic CRUD operations to create, load, view, update, edit.etc for orders made.so this is also working.the problem I seem to be having is creating the table, it is failing when I try to create an entry in the table with 'Quantity'.obviously.so I have changed the code.change 'Quantity' to object, then the plan being to populate this on the VM.but this also didnt work. Var quantities = new ObservableCollection() Public static ObservableCollection GetQuantitiesForProductPage() List_Quantites = PickerService.GetQuantitiesForProductPage() Up Until now I was populating the ProductModel with its picker, from the constructor of the ProductViewModel page with: WineList = new ObservableCollection() Propert圜hanged?.Invoke(this, new Propert圜hangedEventArgs(propertyName)) Protected virtual void OnPropert圜hanged( string propertyName = null) If (e.PropertyName = nameof(SelectedQuantity)) Private void OnPropert圜hanged(object sender, Propert圜hangedEventArgs e) ![]() Public ObservableCollection ListQuantites ETC have removed the other properties for sake of this Q Public ObservableCollection _ListQuantites Public event Propert圜hangedEventHandler Propert圜hanged ProductModel public class ProductModel : INotifyPropert圜hanged To help me include a populated picker using MVVM in my project, using a picker to allowing the user to select a 'Quantity' to order for each product (which all works fine as its populated from code, but now refactoring to load from ease see current code below). Xamarin forms - populate picker in MVVM from SQLite DB issue ![]()
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