wph304. announcement linq to sql linq to user data
TRANSCRIPT
New Windows Phone Data Access Features
Sean McKennaProgram ManagerWindows Phone Application PlatformMicrosoft Corporation
WPH304
During this Session You have a Chance to Win a Windows Phone
announcement
Session Outline
OverviewArchitectureCode-first development
Implementation detailsQueriesInserts, updates, deletes…Database schema upgrades
Performance and best practices
OverviewEnd-user consentSupported account types
Implementation detailsQuerying contactsQuerying appointments
Performance and best practices
LINQ to SQL LINQ to User Data
LINQ to Everything
LINQ
Objects XML SQLUser Data
7 Mango
OData
Complex Schema
Numerous relationships and constraintsExample: shopping list
Seven tablesHundreds of recordsFive 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 dataExample: dictionary app
Three tablesOne 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 cloudCache locallyCombine with user-specific data
Windows Phone
Service cache
User data
Cloudservice
User Data
Filter contactsBirthdays in the next month
Query all appointmentsFind an available time for a meeting
Filter
demo
Mobile Wine CellarManage your wine collection on the go Fetches reference data from wine.com Odata serviceStores user information in local database Queries contacts and appointments for planning wine tasting
Database Support
Local Data Storage: Overview
Apps store private data in Isolated StorageSettings and properties in the app dictionaryUnstructured data in Isolated Storage files Structured data in database files
ApplicationSettings file
AppCreates/managesfiles and settings
Applicationfiles
App Data Folder
Package Manager
App Root Folder
WP7 Isolated Storage APIs
Install
DB
Database file
Databasefile (r/o)
Creates root foldersandboxed to App DB
Architecture
.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”
Your AppCustom
data context
App 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
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
// 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();
Database Creation: Example
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
DataContext
Name Little Penguin
Varietal Pinot Noir
AtHome False
Name Little Penguin
Varietal Pinot Noir
AtHome True
Inserts/Updates/Deletes
It’s all about the DataContextChanges made against the DataContext firstChanges persisted by calling SubmitChanges()
SubmitChangesLINQ 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/Deletes
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();
Insert Update
Inserts/Updates/Deletes
Delete
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
Inserts/Updates/Deletes
var vineyardsToDelete = from Vineyards v in db.Vineyardswhere v.Country == “Australia"
select v;
foreach (Vineyards v in vineyardsToDelete){ db.Wines.DeleteAllOnSubmit(v.Wines);}
db.Vineyards.DeleteAllOnSubmit(vineyardsToDelete);db.SubmitChanges();
Database Schema Upgrades
DatabaseSchemaUpdater allows simple upgrades on your existing DBSupports adding
TablesColumnsIndicesAssociations/foreign keys
DatabaseSchemaVersion available for tracking upgradesSchema updates are transactional
Database Schema Upgrades
WineDataContext wineDC = new WineDataContext(App.WineDBConnectionString);
DatabaseSchemaUpdater dsu = wineDC.CreateDatabaseSchemaUpdater();
if (dsu.DatabaseSchemaVersion == 1){
dsu.AddColumn<Wine>("BottleType");dsu.DatabaseSchemaVersion = 2;
dsu.Execute();}
Performance and Best Practices
Think about the size of your change setsLots of submits will impact performance but limit data loss
Use background threadsOperations on UI thread impact app responsiveness
Optimize read-only queriesSet ObjectTrackingEnabled to minimize memory usage
Performance and Best Practices
Populate large reference data tables in advanceCreate a simple project to prepopulate data in emulatorPull out database file using Isolated Storage explorer
Use the right tool for the jobDatabase for large or complex data setsIsolatedStorageSettings/basic files for small data
Performance and Best Practices
Use a version column on your entitiesUp to 30x improvement in update performance
Use secondary indices for properties which you query oftenImplement INotifyPropertyChanged for efficient change tracking
Avoid creating object copies until needed
demo
Best PracticesINotifyPropertyChangingSecondary indexesVersion column
User Data
New and updated APIs in “Mango”
Chooser Tasks related to user dataEmailAddressChooserTaskPhoneNumberChooserTaskAddressChooserTask
Microsoft.Phone.UserData for direct accessContactsAppointments
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 pointsContacts and Appointments APIs are read onlyThird party social network data cannot be shared
Contacts/Appointments Data Shared
Contact nameand picture
Other 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 responsibleYour privacy policy should cover how you use the user’s contact information
Keep out of the wayUsers have widely varying contact list sizes Your UI should handle delays gracefully
Don’t let data get staleData returned is a snapshotRefresh state when reasonable
demo
Invite Friends for a Wine Tasting
Win a Windows Phone Contest
QUESTIONS?
Go to the WPC Information Counter
at the TLC
HAT CONTEST*
How do you enter?Enter by visiting the Windows Phone booth, accepting a free Windows Phone branded hat, and wearing that hat during the Event
How am I selected?Each day of the event, a Windows Phone representative will randomly select up to 5 people who are observed wearing their Windows Phone branded hat
SESSION CONTEST*
During each Windows Phone session the moderator will post a question; the first person to correctly answer the question and is called on by the moderator will potentially win
* Restrictions apply please see contest rules for eligibility and restrictions. Contest rules are displayed in the Technical Learning Center at the WPH info counter
Windows Phone ResourcesQuestions? Demos? The latest phones?
Visit the Windows Phone Technical Learning Center for demos and more…
Business IT resources
blogs.technet.com/b/windows_phone_4_it_pros
Developer resources
create.msdn.com
Experience Windows Phone 7 on-line and get a backstage pass
www.windowsphone.com
Q&A
Scan the Tag to evaluate this session now on myTech•Ed Mobile
Resources
www.microsoft.com/teched
Sessions On-Demand & Community Microsoft Certification & Training Resources
Resources for IT Professionals Resources for Developers
www.microsoft.com/learning
http://microsoft.com/technet http://microsoft.com/msdn
Learning
http://northamerica.msteched.com
Connect. Share. Discuss.
Complete an evaluation on CommNet and enter to win!
© 2011 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.
