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Windows Phone 7.5( Mango) support SQL CE

Windows Phone 7.5( Mango) suporta SQL CE(SQL Compact Edition). Acest feature era de mult timp asteptat. Acuma sa vedem cum se foloseste.
Baza de date poate sa fie pusa in doua locatii:
  1. isolated storage
  2. installation folder
In functie de locatie si de parametrii, stringul de conexiune poate sa aibe urmatoarea forma:
  • Data Source = 'isostore:/MyDB.sdf; - cand baza de date este in isolated storage
  • Data Source = 'isostore:/MyDB.sdf';Password='1234'; - cand baza de date este in folderul unde aplicatia a fost instalata si este encriptata cu parola 1234
La stringul de conexiue putem sa setam si alte valori precum culture-ul( "Culture Identifier") si daca este case sensitive( "Case Sensitive").
Trebuie sa tinem cont ca avem cateva limitari pe Mango cand vrem sa folosim SQL CE:
  • fisierele sdf sunt stocate si deschise din isolation storage
  • daca dorim un mecanism de ORM este nevoie sa folosim LINQ2SQL
  • T-SQL queries nu este suportat( nu putem sa avem tranzactii)
  • o referinta la System.Data.Linq trebuie adaugata
  • pentru definierea modelului in acest moment avem doua optiuni SQLMetal pentru Windows Phone Mango sau code-first. By default nu avem un tool grafic pentru definirea acestor mapari.
  • formatul la string-ul de conexiune este unul specific
Versiune de SQL CE care este suportata este SQL CE 4.0. Se poate lucra direct cu EF 4.1.
Saptamana urmatoare o sa revin cu un exemplu intreg.


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