Andy WigleyAPPA Mundi

@andy_wigley

http://bit.ly/andywigley

andy.wigley@appamundi.com

New Data Features in “Mango”:SQL Server Compact and User Data Access

LINQ to SQL

• Overview– Architecture– Code-first development

• Implementation details– Queries– Inserts, updates, deletes…– Database schema upgrades

• Performance and best practices

LINQ to User Data

• Overview– End-user consent– Supported account types

• Implementation details– Querying contacts– Querying appointments

• Performance and best practices

Session Outline

LINQ to Everything

LINQ

Objects XML SQL User Data

7 Mango

OData

Complex Schema

• Numerous relationships and constraints

• Example: Shopping List– 7 tables– 100s of records– 5 foreign keys

ItemReferenceData

PK ItemId

ItemName ItemDescriptionFK1 CategoryId

Categories

PK CategoryId

CategoryName

Lists

PK ListId

ListName

ListItems

PK ListItemId

ListItemNameFK1 ListId Quantity Category DescriptionFK2 StoreId

Stores

PK StoreId

StoreName StoreLocationLat StoreLocationLong StoreAddressLine1 StoreAddressLine2 StoreAddressCity StoreAddressState StoreAddressCountry StoryAddressZip

Favorites

PK FavoriteItemId

FavoriteItemName FavoriteItemCategory FavoriteItemQuantity FavoriteItemDescriptionFK1 FavoriteItemListId FavoriteItemPhoto

History

PK HistoryItemId

HistoryItemName HistoryItemCategory HistoryItemQuantity HistoryItemDescriptioin HistoryItemDateAddedFK1 HistoryItemListId HistoryItemPhoto

Reference Data

• Huge amounts of static reference data

• Example: dictionary app– 3 tables– 1 table with 500k rows

Words

PK WordId

Word Pronunciation Definition AlternateSpellings Origin

Favorites

PK FavoriteId

FK1 WordId

History

PK HistoryItemId

FK1 WordId AddedDate

Web Service Cache

• Fetch reference data from cloud

• Cache locally• Combine with user-specific

data

Cloud Service

Windows Phone

Service Cache

User Data

User Data

• Filter contacts– Birthdays in the next

month

• Query all appointments– Find an available time for

a meeting

Filter

Local Database Storage

Demo

Database Support

Local Data Storage: OverviewApps store private data in Isolated Storage Settings and properties in the app dictionary Unstructured data in Isolated Storage files Structured data in database files

ApplicationSettings File

AppCreates/Managesfiles and settings

ApplicationFiles

Iso Store Folder

Creates root foldersandboxed to AppPackage Manager

App Data Folder

WP7 Isolated Storage APIs

Install

DB

Database file

DB DatabaseFile (r/o)

ArchitectureYour AppCustom Data

ContextApp

Objects

System.Data.Linq

Identity Management

Change Tracking

Update Processing

Object Materialization

Microsoft.Phone.Data.Internal

Core ADO.NET (System.Data)

SQLCE ADO.NET Provider (System.Data.SqlServerCe)

SQL CE DB

.Call System.Linq.Queryable.Select( .Call System.Linq.Queryable.Where( .Constant(Table(Wines)), '(.Lambda #Lambda1)), '(.Lambda #Lambda2)) .Lambda #Lambda1(db.Wines $w) { $w.Country == “USA" } .Lambda #Lambda2(w.Country $w) { $w.Name }

var query = from w in db.Wines where w.Country == “USA" select w.Name;

select Namefrom Wineswhere Country = “USA”

Objects, objects, objects…

Design time

Create object model: wines, varietals, vineyards, etc.

Decorate objects with attributes for persistence

Run time

Create DataContext reference to database

Translate object model into a database file

Submit API persists changes to DB

Database upgrade

Create new objects to enable new features

Use upgrade APIs to change DB

Varietals Wines

Vineyards WineMakers

Wines

PK WineID

Name Description RetailPriceFK2 VarietalIDFK1 VineyardID

Vineyards

PK VineyardID

Name Latitude Longitude Country

Varietals

PK VarietalID

Name

Winemaker

PK WinemakerID

FirstName LastName

Database Creation: Example // Define the data context.public partial class WineDataContext : DataContext {

public Table<Wine> Wines;public Table<Vineyard> Vineyards;public WineDataContext(string connection) : base(connection) { }

}

// Define the tables in the database[Table]public class Wine{

[Column(IsPrimaryKey=true]public string WineID { get; set; }[Column]public string Name { get; set; }……

}

// Create the database form data context, using a connection stringDataContext db = new WineDataContext("isostore:/wineDB.sdf");if (!db.DatabaseExists()) db.CreateDatabase();

Queries: Examples

// Create the database form data context, using a connection stringDataContext db = new WineDataContext("isostore:/wineDB.sdf");

// Find all wines currently at home, ordered by date acquiredvar q = from w in db.Wines

where w.Varietal.Name == “Shiraz” && w.IsAtHome == true orderby w.DateAcquired select w;

DB

DataContextName Little

Penguin

Varietal Pinot Noir

AtHome False

Name Little Penguin

Varietal Pinot Noir

AtHome True

Inserts/Updates/Deletes

• It’s all about the DataContext– Changes made against

the DataContext first– Changes persisted

by calling SubmitChanges()

• SubmitChanges– LINQ to SQL determines change

set and submits to DB

Name Little Penguin

Varietal Pinot Noir

AtHome False

Your App Code

Name Yellow Tail

Varietal Pinot Noir

AtHome True

Inserts/Updates/DeletesInsert Update

Wine newWine = new Wine{

WineID = “1768",Name = “Windows Phone Syrah",Description = “Bold and spicy"

};

db.Wines.InsertOnSubmit(newWine);

db.SubmitChanges();

Wine wine = (from w in db.Wines where w.WineID == “1768" select w).First();

wine.Description = “Hints of plum and melon";

db.SubmitChanges();

Inserts/Updates/DeletesDelete

var vineyardsToDelete = from Vineyards v in db.Vineyardswhere v.Country == “Australia”select v;

db.Vineyards.DeleteAllOnSubmit(vineyardsToDelete);

db.SubmitChanges();

Programming SQL Server Compact

Demo

Relationships

• Express one-many, one-one and many-many relationships using EntitySet<T> and EntityRef<T> columns

• In the relational database, a child table has a column – the Foreign Key - that stores the unique ID of a record in the parent table

Words

PK WordId

Word Pronunciation Definition AlternateSpellings Origin

Favorites

PK FavoriteId

FK1 WordId

History

PK HistoryItemId

FK1 WordId AddedDate

Example: Parent Object[Table]     public class Contact : INotifyPropertyChanged, INotifyPropertyChanging{ // Fields           private EntitySet<Lead> leads = new EntitySet<Lead>();

[Association(Storage = "leads", OtherKey = "ContactID")]    public EntitySet<Lead> Leads          {         get { return this.leads; }         set {             InvokePropertyChanging(new PropertyChangingEventArgs("Leads"));             this.leads.Assign(value);             InvokePropertyChanged( new PropertyChangedEventArgs("Leads"));         }          }

Example: Child Object[Table]     [Index (Name="ContactID_Idx", Columns="ContactID", IsUnique=false)]public class Lead : INotifyPropertyChanged, INotifyPropertyChanging     {  private EntityRef<Contact> contact;

   [Column]    public long ContactID {get; set; }

    [Association(Storage = "contact", ThisKey = "ContactID", IsForeignKey=true)]          public Contact Contact    {        get { return this.contact.Entity; }        set {           InvokePropertyChanging(new PropertyChangingEventArgs("Contact"));                  this.contact.Entity = value;           InvokePropertyChanged(new PropertyChangedEventArgs("Contact"));                  if (value != null)               this.ContactID = value.ContactID;         }    }

DeletesDelete

var vineyardsToDelete = from Vineyards v in db.Vineyardswhere v.Country == “Australia”select v;

db.Vineyards.DeleteAllOnSubmit(vineyardsToDelete);

db.SubmitChanges();

Foreign key constraint will cause exception here if Wines associated with the Vineyards are not deleted first

Delete Child Objects Firstvar vineyardsToDelete = from Vineyards v in db.Vineyards

where v.Country == “Australia" select v;

foreach (Vineyards v in vineyardsToDelete){ db.Wines.DeleteAllOnSubmit(v.Wines);}

db.Vineyards.DeleteAllOnSubmit(vineyardsToDelete);db.SubmitChanges();

Entity RelationshipsForeign Keys

Demo

Database Schema Upgrades• DatabaseSchemaUpdater allows simple upgrades

on your existing DB• Supports adding

– Tables– Columns– Indices– Associations/foreign keys

• Schema updates are transactional

Database Schema UpgradesWineDataContext wineDC = new WineDataContext(App.WineDBConnectionString);

DatabaseSchemaUpdater dsu = wineDC.CreateDatabaseSchemaUpdater();

if (dsu.DatabaseSchemaVersion == 1){

dsu.AddColumn<Wine>("BottleType");dsu.DatabaseSchemaVersion = 2;

dsu.Execute();}         

Schema Upgrades

Demo

Performance and Best Practices

• Keep change sets small– Submit early and often to avoid data loss on app termination

• Use background threads– Non-trivial operations will impact app responsiveness if done on UI

thread• Optimize read-only queries

– Set ObjectTrackingEnabled to minimize memory usage• Use secondary indices for properties which you query

often

Performance and Best Practices

• Populate large reference data tables in advance– Create a simple project to prepopulate data in emulator– Pull out database file using Isolated Storage explorer

• Use the right tool for the job– Database for large or complex data sets– IsolatedStorageSettings or basic files for small

data sets

User Data

New and updated APIs in “Mango”

• Chooser Tasks related to user data– EmailAddressChooserTask– PhoneNumberChooserTask– AddressChooserTask

• Microsoft.Phone.UserData for direct access– Contacts– Appointments

AddressChooserTaskprivate AddressChooserTask addressChooserTask;

// Constructorpublic MainPage(){ this.addressChooserTask = new AddressChooserTask(); this.addressChooserTask.Completed += new

EventHandler<AddressResult>( addressChooserTask_Completed);

}

private void addressChooserTask_Completed(object sender, AddressResult e){ if (null == e.Error && TaskResult.OK == e.TaskResult) {

... = e.DisplayName;

... = e.Address; }}

Contacts and Appointments

• Important points– Contacts and Appointments APIs are read

only– Third party social network data cannot be

shared

Contacts/Appointments Data Shared Contact Name

and PictureOther contact data Appointments/Events

Windows Live Social YES YES YES

Windows Live Rolodex(user created and SIM import)

YES YES n/a

Exchange accounts(corporate plus Google, etc.)

YES YES YES

Operator Address Books YES YES n/a

Facebook YES NO NO

Other networks in the People Hub (e.g., Twitter)

NO NO NO

Contacts: Hello, World!Contacts contacts = new Contacts();

contacts.SearchCompleted += new EventHandler<ContactsSearchEventArgs>((sender, e) => { ... = e.Results; });

// E.g. search for all contactscontacts.SearchAsync(string.Empty, FilterKind.None, null);

filter expression(not a regex)

Filter kind: name, email , phone or pinned to start)

state

// E.g. search for all contacts with display name matching "ja"contacts.SearchAsync("ja", FilterKind.DisplayName, null);

Appointments: Hello, World!Appointments appointments = new Appointments();

appointments.SearchCompleted += new EventHandler<AppointmentsSearchEventArgs>((sender, e) => { ... = e.Results; });

// E.g. get next appointment (up to 1 week away)appointments.SearchAsync(DateTime.Now, DateTime.Now + TimeSpan.FromDays(7), 1, null);

start date and time

Maximum items to return stateend date and time

Performance and Best Practices• Be responsible

– Your privacy policy should cover how you use the user’s contact information

• Keep out of the way– Users have widely varying contact list sizes – Your UI should handle delays gracefully

• Don’t let data get stale– Data returned is a snapshot– Refresh state when reasonable

Accessing User Data

Demo

Q&A

© 2008 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries. The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.